Takkenberg, J.J.M.

Surgical outcome of discrete subaortic stenosis in adults a multicenter study (Article)

2013-03-19T00:00:00Z

Background: Discrete subaortic stenosis is notable for its unpredictable hemodynamic progression in childhood and high reoperation rate; however, data about adulthood are scarce. Methods and Results: Adult patients who previously underwent surgery for discrete subaortic stenosis were included in this retrospective multicenter cohort study. Mixed-effects and joint models were used to assess the postoperative progression of discrete subaortic stenosis and aortic regurgitation, as well as reoperation. A total of 313 patients at 4 centers were included (age at baseline, 20.2 years [25th-75th percentile, 18.4-31.0 years]; 52% male). Median follow-up duration was 12.9 years (25th-75th percentile, 6.2-20.1 years), yielding 5617 patient-years. The peak instantaneous left ventricular outflow tract gradient decreased from 75.7±28.0 mm Hg preoperatively to 15.1±14.1 mm Hg postoperatively (P<0.001) and thereafter increased over time at a rate of 1.31±0.16 mm Hg/y (P=0.001). Mild aortic regurgitation was present in 68% but generally did not progress over time (P=0.76). A preoperative left ventricular outflow tract gradient ≥80 mm Hg was a predictor for progression to moderate aortic regurgitation postoperatively. Eighty patients required at least 1 reoperation (1.8% per patient-year). Predictors for reoperation included female sex (hazard ratio, 1.53; 95% confidence interval, 1.02-2.30) and left ventricular outflow tract gradient progression (hazard ratio, 1.45; 95% confidence interval, 1.31-1.62). Additional myectomy did not reduce the risk for reoperation (P=0.92) but significantly increased the risk of a complete heart block requiring pacemaker implantation (8.1% versus 1.7%; P=0.005). Conclusions: Survival is excellent after surgery for discrete subaortic stenosis; however, reoperation for recurrent discrete subaortic stenosis is not uncommon. Over time, the left ventricular outflow tract gradient slowly increases and mild aortic regurgitation is common, although generally nonprogressive over time. Myectomy does not show additional advantages, and because it is associated with an increased risk of complete heart block, it should not be performed routinely.

Data Resource Profile: Adult cardiac surgery database of the Netherlands Association for Cardio-Thoracic Surgery (Article)

2012-12-18T00:00:00Z

n 2007 The Netherlands Association for Cardio-Thoracic Surgery (Nederlandse Vereniging voor Thoraxchirurgie, NVT) instituted the Adult Cardiac Surgery Database. The dataset comprises demographic factors, type of intervention, in-hospital mortality and 18 risk factors for mortality after cardiac surgery, according to the European System for Cardiac Operative Risk Evaluation definitions. Currently, this procedural database contains over 60 000 interventions. Completeness of data is excellent and national coverage of all 16 Dutch cardio-thoracic surgery centres has been achieved since the start. The primary goal of the database is to control and maintain the quality of care by evaluation of outcomes. This is accomplished by regular feedback and comparison of outcomes. For a subset of the database (procedures from 10 out of 16 centres) longer-term follow-up has been established by means of data linkage to two national registries. This provides information on survival status, causes of death and readmissions. The database has recently been used for research, resulting in methodological papers aimed at optimizing comparison of outcomes. In future, clinical issues will also be addressed, for example survival after coronary artery bypass grafting and valve surgery.

Microsimulation for Clinical Decision-Making in Individual Patients With Established Coronary Artery Disease (Article)

2012-11-29T00:00:00Z

Background: In cardiovascular disease, numerous evidence-based prognostic models have been created, usually based on regression analyses of isolated patient datasets. They tend to focus on one outcome event, based on just one baseline evaluation of the patient, and fail to take the disease process in its dynamic nature into account. We present so-called microsimulation as an attractive alternative for clinical decision-making in individual patients. We aim to further familiarize clinicians with the concept of microsimulation and to inform them about the modeling process. Methods and Results: We describe the modeling process, advantages and disadvantages of microsimulation. We illustrate the concept using a hypothetical 60-year-old patient, with several cardiac risk factors, who is hospitalized for myocardial infarction. By using microsimulation, we calculate this patient’s probability of death. In our example, this particular patient’s estimated life expectancy turns out to be 8.9 years. While calculating this life expectancy, we were able to account for multiple outcome events and changing patient characteristics. Conclusions: Microsimulation takes into account the dynamic nature of coronary artery disease by estimating most likely outcomes regarding a broad range of clinical events. Moreover, microsimulation can be used to evaluate treatment effects by estimating the event-free life expectancy with and without treatment. Hence, microsimulation has several advantages compared to modeling techniques such as regression.

Reoperations on the pulmonary autograft and pulmonary homograft after the Ross procedure: An update on the German Dutch Ross Registry (Article)

2012-10-01T00:00:00Z

Objectives: Reinterventions after the Ross procedure are a concern for patients and treating physicians. The scope of the present report was to provide an update on the reinterventions observed in the large patient population of the German-Dutch Ross Registry. Patients and Methods: From 1988 to 2011, 2023 patients (age, 39.05 ± 16.5 years; male patients, 1502; adults, 1642) underwent a Ross procedure in 13 centers. The mean follow-up was 7.1 ± 4.6 years (range, 0-22 years; 13,168 patient-years). Results: In the adult population, 120 autograft reinterventions in 113 patients (1.03%/patient-year) and 76 homograft reinterventions in 67 patients (0.65%/patient-year) and, in the pediatric population, 14 autograft reinterventions in 13 patients (0.91%/patient-year) and 42 homograft reinterventions in 31 patients (2.72%/patient-year) were observed. Of the autograft and homograft reinterventions, 17.9% and 21.2% were performed because of endocarditis, respectively. The subcoronary technique in the adult population resulted in significantly superior autograft durability (freedom from autograft reintervention: 97% at 10 years and 91% at 12 years; P < .001). The root replacement technique without root reinforcement (hazard ratio, 2.4; 95% confidence interval, 1.4-4.1) and the presence of pure aortic insufficiency preoperatively (hazard ratio, 2.3; 95% confidence interval, 1.5-3.5) were statistically significant predictors for a shorter time to reoperation. The center volume had a significant influence on the long-term results. The freedom from homograft reoperation for the adults and pediatric population was 97% and 87% at 5 years and 93% and 79% at 12 years, respectively (P < .001), with younger recipient and donor age being significant predictors of a shorter time to homograft reoperation. Conclusions: The autograft principle remains a valid option for young patients requiring aortic valve replacement. The risk of reoperation depends largely on the surgical technique used and the preoperative hemodynamics. Center experience and expertise also influence the long-term results. Adequate endocarditis prophylaxis might further reduce the need for reoperation.

Autograft and pulmonary allograft performance in the second post-operative decade after the Ross procedure: insights from the Rotterdam Prospective Cohort Study (Article)

2012-09-01T00:00:00Z

The objective of the present study was to report our ongoing prospective cohort of autograft recipients with up to 21 years of follow-up. All consecutive patients (n = 161), operated between 1988 and 2010, were analysed. Mixed-effects models were used to assess changes in echocardiographic measurements (n = 1023) over time in both the autograft and the pulmonary allograft. The mean patient age was 20.9 years (range 0.05-52.7)-66.5% were male. Early mortality was 2.5% (n = 4), and eight additional patients died during a mean follow-up of 11.6 ± 5.7 years (range 0-21.5). Patient survival was 90% [95% confidence interval (CI), 78-95] up to 18 years. During the follow-up, 57 patients required a re-intervention related to the Ross operation. Freedom from autograft reoperation and allograft re-intervention was 51% (95% CI 38-63) and 82% (95% CI 71-89) after 18 years, respectively. No major changes were observed over time in autograft gradient, and allograft gradient and regurgitation. An initial increase of sinotubular junction and aortic anulus diameter was observed in the first 5 years after surgery. The only factor associated with an increased autograft reoperation rate was pre-operative pure aortic regurgitation (AR) (hazard ratio 1.88; 95% CI 1.04-3.39; P= 0.037). We observed good late survival in patients undergoing autograft procedure without reinforcement techniques. However, over half of the autografts failed prior to the end of the second decade. The reoperation rate and the results of echocardiographic measurements over time underline the importance of careful monitoring especially in the second decade after the initial autograft operation and in particular in patients with pre-operative AR.

Invited commentary (Article)

2012-01-01T00:00:00Z

Birth prevalence of congenital heart disease worldwide: A systematic review and meta-analysis (Article)

2011-11-15T00:00:00Z

Congenital heart disease (CHD) accounts for nearly one-third of all major congenital anomalies. CHD birth prevalence worldwide and over time is suggested to vary; however, a complete overview is missing. This systematic review included 114 papers, comprising a total study population of 24,091,867 live births with CHD identified in 164,396 individuals. Birth prevalence of total CHD and the 8 most common subtypes were pooled in 5-year time periods since 1930 and in continent and income groups since 1970 using the inverse variance method. Reported total CHD birth prevalence increased substantially over time, from 0.6 per 1,000 live births (95% confidence interval [CI]: 0.4 to 0.8) in 1930 to 1934 to 9.1 per 1,000 live births (95% CI: 9.0 to 9.2) after 1995. Over the last 15 years, stabilization occurred, corresponding to 1.35 million newborns with CHD every year. Significant geographical differences were found. Asia reported the highest CHD birth prevalence, with 9.3 per 1,000 live births (95% CI: 8.9 to 9.7), with relatively more pulmonary outflow obstructions and fewer left ventricular outflow tract obstructions. Reported total CHD birth prevalence in Europe was significantly higher than in North America (8.2 per 1,000 live births [95% CI: 8.1 to 8.3] vs. 6.9 per 1,000 live births [95% CI: 6.7 to 7.1]; p < 0.001). Access to health care is still limited in many parts of the world, as are diagnostic facilities, probably accounting for differences in reported birth prevalence between high- and low-income countries. Observed differences may also be of genetic, environmental, socioeconomical, or ethnic origin, and there needs to be further investigation to tailor the management of this global health problem.

No ross operation for patients with aortic regurgitation? (Article)

2011-09-01T00:00:00Z

Washing of irradiated red blood cells in paediatric cardiopulmonary bypass: is it clinically useful? A retrospective audit (Article)

2011-08-02T00:00:00Z

Objective: Despite the introduction of smaller cardiopulmonary bypass (CPB) circuits for paediatrics, it is frequently necessary to add irradiated red blood cell concentrate (IRBC) to maintain adequate haemoglobin levels and the oxygen carrying capacity. Irradiation of blood weakens the cell membranes and results in an increase of lactate and potassium concentration. In addition, prolonged shelf time of IRBC may enhance its lactate level. To avoid the adverse effects of increased lactate and potassium concentration during paediatric bypass, prewashing of homologous blood in a cell-saving device was implemented at our institution. A retrospective audit of clinical data was performed to assess the relevance of this method. Methods: Preceding the introduction of the blood pre-washing, we investigated 14 units of IRBC for lactate, potassium levels and shelf time. Afterwards, we evaluated the CPB and laboratory data from 69 patients with body weight <10 kg and the lactate levels in the priming of the bypass circuit. Results: The shelf time of blood units was 7.6 ± 2.7 days (minimum 5, maximum 14 days) with lactate concentration of 12.6 ± 2 mmol/l and potassium concentration of 16.2 ± 4.7 mmol/l. In the priming after pre-washing, the lactate concentration was significantly lower than the standard priming (2.5 ± 0.9 vs 4.5 ± 20 mmol/l, p = 0.002). At the start of bypass, the lactate concentration after pre-washing was still lower (1.5 ± 0.4 vs 1.9 ± 0.9 mmol/l; p = 0.04), but at the end of bypass we detected a significant increase of lactate in the pre-washed group (1.5 ± 0.4 vs 2.2 ± 1.1 mmol/l, p = 0.01). There was no significant difference between the groups at the end of bypass (1.8 ± 0.9 vs 2.2. ± 1.1 mmol/l, p = 0.17). Other clinical and patient data were not significantly different. Conclusions: Our retrospective audit shows that pre-washing of IRBCs is not associated with decreased lactate levels at the end of CPB compared with standard use of IRBCs, suggesting that the added value of pre-washing of IRBCs on minimisation of lactate levels during CPB remains doubtful.

Intraoperative glycemic control without insulin infusion during pediatric cardiac surgery for congenital heart disease (Article)

2011-08-01T00:00:00Z

Summary Background: Many studies are reporting that the occurrence of hyperglycemia in the postoperative period is associated with increased morbidity and mortality rates in children after cardiac surgery for congenital heart disease. This study sought to determine blood glucose levels in standard pediatric cardiac anesthesiological management without insulin infusions. Methods: The study population consisted of 204 consecutive pediatric patients aged from 3 days to 15.4 years undergoing open cardiac surgery for congenital heart disease between June 2007 and January 2009. Glucose-containing fluids were not administrated intraoperatively, and all patients received high dose of opioids (sufentanil 10 mcg·kg-1) and steroids (30 mg·kg-1methylprednisolone) iv. Glucose levels were measured before CPB, 10 min after initiation of CPB, every hour on CPB, post-CPB, and on arrival at intensive care unit (ICU). Results: Intraoperatively, only one patient had a glucose level <50 mg·dl-1(=34.2 mg·dl-1), 57/204 patients (27.9%) had at least one intraoperative glucose >180 mg·dl-1, but only 12 patients (5.8%) had a glucose level >180 mg·dl-1at ICU arrival. Thirty-day mortality was 1.5% (3/204). Younger age, lower body weight, and lower CPB temperature were associated with hyperglycemia at ICU arrival, as were higher RACHS and Aristotle severity scores. Conclusion: A conventional (no insulin, no glucose) anesthetic management seems sufficient in the vast majority of patients (96.5%). Special attention should be paid to small neonates with complex congenital heart surgery, in whom insulin treatment may be contemplated.

Effects of rosuvastatin on progression of stenosis in adult patients with congenital aortic stenosis (PROCAS Trial) (Article)

2011-07-15T00:00:00Z

Recent trials have failed to show that statin therapy halts the progression of calcific aortic stenosis (AS). We hypothesized that statin therapy in younger patients with congenital AS would be more beneficial, because the valve is less calcified. In the present double-blind, placebo-controlled trial, 63 patients with congenital AS (age 18 to 45 years) were randomly assigned to receive either 10 mg of rosuvastatin daily (n = 30) or matched placebo (n = 33). The primary end point was the progression of peak aortic valve velocity. The secondary end points were temporal changes in the left ventricular mass, ascending aortic diameter, and N-terminal pro-brain natriuretic peptide (NT-proBNP). The median follow-up was 2.4 years (interquartile range 1.9 to 3.0). The mean increase in peak velocity was 0.05 ± 0.21 m/s annually in the rosuvastatin group and 0.09 ± 0.24 m/s annually in the placebo group (p = 0.435). The annualized change in the ascending aorta diameter (0.4 ± 1.7 mm with rosuvastatin vs 0.5 ± 1.6 mm with placebo; p = 0.826) and left ventricular mass (1.1 ± 15.8 g with rosuvastatin vs -3.7 ± 30.9 g with placebo; p = 0.476) were not significantly different between the 2 groups. Within the statin group, the NT-proBNP level was 50 pg/ml (range 19 to 98) at baseline and 21 pg/ml (interquartile range 12 to 65) at follow-up (p = 0.638). NT-proBNP increased from 40 pg/ml (interquartile range 20 to 92) to 56 pg/ml (range 26 to 130) within the placebo group (p = 0.008). In conclusion, lipid-lowering therapy with rosuvastatin 10 mg did not reduce the progression of congenital AS in asymptomatic young adult patients. Interestingly, statins halted the increase in NT-proBNP, suggesting a potential positive effect of statins on cardiac function in young patients with congenital AS.

Re-operations for aortic allograft root failure: Experience from a 21-year single-center prospective follow-up study (Article)

2011-07-01T00:00:00Z

Objective: The study aims to report results of re-operations after aortic allograft root implantation. Methods: All consecutive patients in our prospective allograft database, who underwent aortic allograft root implantation, were selected for analysis, and additional information for patients who subsequently underwent re-operation was obtained from hospital records. Results: From 1989 to 2009, 262 aortic allograft root implantations were performed. Thirty-day mortality was 5.7%. During follow-up, 69 patients died. The actuarial survival was 77.0% (95% confidence interval (CI) 71-83%) after 10 years, and 65.1% (95% CI 57-74%) after 14 years. A total of 52 patients required re-operation. The actuarial freedom from allograft re-operation was 82.9% (Standard Error (SE) 2.9%) after 10 years and 55.7% (SE 5.7%) after 14 years. The actuarial median time to re-operation was 14.8 years. The indications for re-operation were structural valve dysfunction in 46 patients, endocarditis in two patients and non-structural valve dysfunction in four patients. The re-operations included 23 aortic valve replacements (mechanical prostheses 20 and bioprostheses 3), 27 aortic root replacements (mechanical conduits 21, aortic allografts five, and biological conduit one), one trans-apical valve implantation and one primary closure of a false aneurysm. The additional procedures were mitral valve repair (N=5), mitral valve replacement (N=1), ascending aortic replacement (N=5), and coronary artery bypass grafting (CABG) (N=4; in two patients unforeseen). Thirty-day mortality after re-operation occurred in two patients (3.9%). Five patients died during follow-up. The survival after re-operation was 87.1% (SE 5.5%) after 1 year and 79.3% (SE 7.4%) after 9 years. Conclusions: Re-operations after aortic allograft root implantation will be required in a substantial and growing number of patients. These re-operations, although technically demanding, can be performed with satisfying results.

Right ventricular outflow tract reconstruction with an allograft conduit in patients after tetralogy of fallot correction: Long-term follow-up (Article)

2011-07-01T00:00:00Z

Background: In tetralogy of Fallot (TOF) pulmonary regurgitation is a frequent complication after initial repair. The objective of the present study was to describe the long-term experience with the use of allograft conduits for right ventricular outflow tract (RVOT) reconstruction after correction of TOF in our institution. Methods: Between 1987 and 2009, 133 allografts were implanted in 126 patients (mean age, 27.8 years). The mean time from initial TOF repair to allograft implantation was 20.8 ± 8.8 years. Kaplan-Meier analyses were done for patient survival, freedom from allograft replacement and freedom from any cardiovascular event. Results: Hospital mortality was 1.5% (2 patients). Mean follow-up was 8.1 years. Ten other patients died during late follow-up, in 8 patients the cause was heart failure. Patient survival was 95% at 5 years, 91% at 10 years, and 80% at 15 years. Male sex, older patient age at the time of operation, and the use of preoperative diuretics were associated with increased risk of mortality during follow-up. Freedom from allograft replacement was 83% at 10 years and 70% at 15 years. Freedom from any valve-related event was 80% at 10 years and 67% at 15 years. Conclusions: Right ventricular outflow tract reconstruction after previous TOF repair can be performed with low risk and a low reintervention rate. Allograft conduits function satisfactorily in the pulmonary position at longer-term follow-up. Functional status after allograft implantation in patients with a previous correction of TOF remains good. There is concern about the long-term survival and the occurrence of heart failure.

Right ventricular outflow tract reconstruction: The impact of allograft characteristics (Article)

2011-06-01T00:00:00Z

Surgical management of aortic root disease in Marfan syndrome: A systematic review and meta-analysis (Article)

2011-06-01T00:00:00Z

Context: Surgical treatment of aortic root aneurysm in Marfan syndrome (MFS) patients. Objective: To compare results of total root replacement versus valve-sparing aortic root replacement in MFS patients. Data Sources: PubMed, Embase and Cochrane library were searched from January 1966 until February 2010 looking for papers reporting on aortic root operations in MFS patients. 530 studies were retrieved. Study Selection: Finally, 11 publications were enrolled. Inclusion criteria were observational studies reporting valve-related morbidity and mortality after total root replacement (TTR) and/or valve-sparing root replacement (VSRR) in patients with MFS and study size n≥30, reflecting the centre's experience. Data Extraction: Data obtained from papers reporting both TRR and VSRR cohorts were analysed separately. In case of multiple publications, the most recent and complete report was selected. If the total number of patient-years was not provided, we calculated it by multiplying the number of hospital survivors with the mean follow-up duration of that study. Results: Overall, 1385 patients were analysed (972 patients had TTR and 413 patients had VSRR). Reintervention rate was 0.3%/year (95% CI 0.1 to 0.5) versus 1.3%/year (95% CI 0.3 to 2.2) (p=0.02) and thromboembolic events rate was 0.7%/year (95% CI 0.5 to 0.9) versus 0.3%/year (95% CI 0.1 to 0.6) (p=0.01) after TRR and VSRR, respectively. When composite valve-related events were compared, no difference existed between the two surgical strategies (p=0.41). Among patients undergoing VSRR, reimplantation was associated with a reduced rate of reintervention compared with remodelling (0.7%/year vs 2.4%/year, p=0.02). Conclusions: VSRR may represent a valuable option for patients with MFS with aortic aneurysm. However, this technique should be used with caution in patients with valve characteristics at risk for decreased durability.

A crucial factor in shared decision making: The team approach (Article)

2011-05-28T00:00:00Z

Survival of surgically treated infective endocarditis: A comparison with the general dutch population (Article)

2011-05-01T00:00:00Z

Background: Infective endocarditis (IE) remains associated with high in-hospital and long-term mortality. The outcome of patients with IE who are operated on has never been put into perspective by comparing it to the age-matched and gender-matched general population. The aim of the present study was to evaluate the long-term mortality of patients with IE who undergo operation in relation to the age-matched and gender-matched general population. Methods: A retrospective observational cohort study of 138 patients with IE who underwent consecutive operations (19982007) was conducted. Cumulative survival was analyzed using the Kaplan-Meier method. Comparison of patient survival with the general population was done using the Dutch population life table. The standardized mortality ratio was used to assess the degree of late deaths. Results: The observed in-hospital mortality risk was 10.9%. The observed long-term survival was 85% (95% confidence interval, 78% to 90%), 74% (95% confidence interval, 65% to 79%), 71% (95% confidence interval, 62% to 78%) after 1, 5, and 10 years, respectively. Age-matched and gender-matched survival in the general population was 99%, 93%, and 80% after a follow-up period of 1, 5, and 10 years, respectively. The standardized mortality ratio was 0.99 (95% confidence interval, 0.67 to 1.31). Conclusions: Although mortality of IE patients who have undergone operation remains considerable during the immediate postoperative period, the mortality of hospital survivors is, with increasing follow-up time, comparable with the general population.

Long-term outcome of right ventricular outflow tract reconstruction with bicuspidalized homografts (Article)

2011-04-21T00:00:00Z

Objective: Given the shortage of small-sized cryopreserved homografts for right ventricle (RV) to pulmonary artery (PA) reconstructions, more readily available larger-sized homografts can be used after size reduction by bicuspidalization. The aim of our study was to determine and compare function over time of standard and bicuspidalized homografts in infants younger than 12 months, including patients with a Ross or extended Ross procedure. Methods: All consecutives infants under the age of 1 year, who underwent a surgical procedure in which a homograft was placed in the RV-PA position between January 1994 and April 2009, were included. Prospectively collected data from serial, standardized echocardiography from all patients were extracted from the database, and hospital records were retrospectively reviewed. Results: A total of 40 infants had a valved homograft conduit placed in the RV-PA position. In 20 of those patients, a bicuspidalized homograft was used. Twelve patients underwent a Ross procedure, of whom seven had an additional Konno-type aortic annulus enlargement. Median follow-up was 146 months (interquartile range (IQR), 117-170; total patient years: 178) in the group with standard use of the homograft and 95 months (IQR, 11-104; total patient years: 78) in the group with bicuspidalized conduits. Freedom from re-intervention (re-operation or percutaneous) was not different in the standard and bicuspidalized groups for all and Ross or Konno-Ross procedures (Tarone-Ware, p = 0.65 and p = 0.47, respectively). Consecutive echocardiographic maximum velocities in the right ventricular outflow tract were similar in the standard and bicuspidalized groups. Conclusion: When proper sized cryopreserved homografts for placement in the RV-PA position in Ross, Konno-Ross, and other procedures in infants under the age of 1 year are not readily available, bicuspidalized homografts provide an acceptable alternative.

Risk stratification for adult congenital heart surgery (Article)

2011-04-01T00:00:00Z

Objective: At this moment, no risk stratification models are available for adult congenital cardiac surgery. This study aims to identify a suitable stratification tool for the adult congenital heart surgery population. Pediatric congenital cardiac surgery score models were therefore tested in an adult congenital population. In addition, an age component was added to these models and performance was compared with the original score systems. Methods: The Risk Adjustment in Congenital Heart Surgery (RACHS-1), Basic Aristotle Score, Society of Thoracic Surgeons (STS)-European Association for Cardiothoracic Surgery (EACTS) Score and Comprehensive Aristotle Score were calculated for all adult patients who underwent congenital cardiac surgery between January 1990 and January 2007 in a single center (N= 963). In addition, an age component was added to these models. Discrimination was then tested for all models with and without the age component. Results: Application of the original pediatric risk scores resulted in c-statistics for 30-day mortality of 0.60, 0.60, 0.60, and 0.66 respectively. Combining these models with the age component resulted in significantly higher c-statistics of 0.69, 0.70, 0.69, and 0.76 respectively. Age as a sole predictor already resulted in a c-statistic of 0.67. Comparable results were found for 1-year mortality. Conclusions: The discriminatory power of the pediatric risk scores was suboptimal, but increased when adding age as a score component. The best performance was achieved by the combination of age and the Comprehensive Aristotle Score, for both 30-day and 1-year mortality.

Survival comparison of the ross procedure and mechanical valve replacement with optimal self-management anticoagulation therapy: Propensity-matched cohort study (Article)

2011-01-04T00:00:00Z

Background-: It is suggested that in young adults the Ross procedure results in better late patient survival compared with mechanical prosthesis implantation. We performed a propensity score-matched study that assessed late survival in young adult patients after a Ross procedure versus that after mechanical aortic valve replacement with optimal self-management anticoagulation therapy. Methods and results-: We selected 918 Ross patients and 406 mechanical valve patients 18 to 60 years of age without dissection, aneurysm, or mitral valve replacement who survived an elective procedure (1994 to 2008). With the use of propensity score matching, late survival was compared between the 2 groups. Two hundred fifty-three patients with a mechanical valve (mean follow-up, 6.3 years) could be propensity matched to a Ross patient (mean follow-up, 5.1 years). Mean age of the matched cohort was 47.3 years in the Ross procedure group and 48.0 years in the mechanical valve group (P≤0.17); the ratio of male to female patients was 3.2 in the Ross procedure group and 2.7 in the mechanical valve group (P≤0.46). Linearized all-cause mortality rate was 0.53% per patient-year in the Ross procedure group compared with 0.30% per patient-year in the mechanical valve group (matched hazard ratio, 1.86; 95% confidence interval, 0.58 to 5.91; P≤0.32). Late survival was comparable to that of the general German population. Conclusions-: In comparable patients, there is no late survival difference in the first postoperative decade between the Ross procedure and mechanical aortic valve implantation with optimal anticoagulation self-management. Survival in these selected young adult patients closely resembles that of the general population, possibly as a result of highly specialized anticoagulation self-management, better timing of surgery, and improved patient selection in recent years. Copyright © 2011 American Heart Association.

Clinical outcome and health-related quality of life after right-ventricular-outflow-tract reconstruction with an allograft conduit (Article)

2010-12-06T00:00:00Z

Objective: Allograft conduits are used for reconstruction of the right ventricular outflow tract in congenital heart malformations (biventricular repair) and autograft procedures. A retrospective evaluation of allograft reconstruction of the right-ventricular-outflow-tract reconstruction was conducted and a cross-sectional quality of life study was performed. Methods: Between August 1986 and March 2009, 509 allografts (435 pulmonary and 74 aortic) were implanted in 463 pediatric and adult patients (308 right-sided congenital heart malformations and 155 autograft procedures). Perioperative and follow-up data were collected and analyzed. Kaplan-Meier analyses were done for survival, valve-related re-operation, and valve-related events. Cox regression analysis was used for evaluation of potential risk factors. In addition, the Short Form-36 was presented to patients to assess the perceived quality of life. The results of the Short Form-36 were compared to age-adjusted Dutch population norms. Results: The mean age at allograft implantation was 19 years (1 week-66 years). Mean follow-up was 9 years (2 days-22 years). Forty-eight patients died during follow-up. Patient survival was 93% at 10 years and 88% at 15 years. A total of 63 re-operations were required for allograft dysfunction in 58 patients. Freedom from valve-related re-operation was 89% at 10 years and 81% at 15 years. Freedom from valve-related events was 86% at 10 years and 74% at 15 years. Younger patient age (p = 0.007) and the use of an aortic allograft (p < 0.001) were identified as independent risk factors for allograft re-operation. Patients between 14 and 40 years scored significantly lower on 'physical functioning' and 'general health' subscales than the general Dutch population, but scored better on the subscales 'emotional role functioning' and 'bodily pain'. Except for the subscale 'general health', on which patients within our study population scored lower, patients between 41 and 60 years had comparable average scores as the general Dutch population. The older patient group (61 years or older) had a better average score on the subscale 'bodily pain' and similar scores on other subscales with respect to the general Dutch population. Conclusions: Right-ventricular-outflow-tract reconstruction with an allograft conduit can be performed with good patient survival, acceptable long-term allograft durability, and good perceived quality of life.

Aortic root reoperations after pulmonary autograft implantation (Article)

2010-12-01T00:00:00Z

Objective: To report the results of aortic root reoperations after pulmonary autograft implantation. Methods: All consecutive patients in our prospective Ross research database were selected for analysis, and additional information for patients requiring reoperation was obtained from the hospital records. Results: From 1988 to 2009, 155 pulmonary autograft operations were performed. During this period, 41 patients required reoperation for aortic root dilatation and/or autograft valve insufficiency, in 8 patients combined with pulmonary allograft dysfunction. The freedom from autograft reoperation rate was 86% (standard error, 3.3%) after 10 years and 52% (standard error, 6.6%) after 15 years. The median interval to reoperation was 15.3 years. During reoperation, 39 patients underwent aortic root replacement (mechanical conduit, 31; stentless root, 2; allograft, 3; and valve sparing, 3), and 2 patients underwent valve replacement. In 8 patients this was combined with pulmonary allograft replacement. The technical difficulties encountered included bleeding at the sternal re-entry in 5 patients. No 30-day mortality occurred. The postoperative complications included reexploration for persistent blood loss in 3 patients and cerebrovascular accident in 3 patients. Two patients died during the follow-up period. The survival rate after reoperation was 94% (standard error, 4.1%) at 5 years. Conclusions: An increasing number of patients requires reoperation after pulmonary autograft implantation. These reoperations can be done with very low mortality and morbidity and excellent follow-up results.

Biological valves: Is durability really the bottle neck? (Article)

2010-11-01T00:00:00Z

Major adverse cardiac and cerebrovascular events after the ross procedure: A report from the german-dutch ross registry (Article)

2010-09-14T00:00:00Z

Background-: The purpose of the study is to report major cardiac and cerebrovascular events after the Ross procedure in the large adult and pediatric population of the German-Dutch Ross registry. These data could provide an additional basis for discussions among physicians and a source of information for patients. Methods and results-: One thousand six hundred twenty patients (1420 adults; 1211 male; mean age, 39.2±16.2 years) underwent a Ross procedure between 1988 and 2008. Follow-up was performed on an annual basis (median, 6.2 years; 10 747 patient-years). Early and late mortality were 1.2% (n=19) and 3.6% (n=58; 0.54%/patient-year), respectively. Ninety-three patients underwent 99 reinterventions on the autograft (0.92%/patient-year); 78 reinterventions in 63 patients on the pulmonary conduit were performed (0.73%/patient-year). Freedom from autograft or pulmonary conduit reoperation was 98.2%, 95.1%, and 89% at 1, 5, and 10 years, respectively. Preoperative aortic regurgitation and the root replacement technique without surgical autograft reinforcement were associated with a greater hazard for autograft reoperation. Major internal or external bleeding occurred in 17 (0.15%/patient-year), and a total of 38 patients had composite end point of thrombosis, embolism, or bleeding (0.35%/patient-year). Late endocarditis with medical (n=16) or surgical treatment (n=29) was observed in 38 patients (0.38%/patient-year). Freedom from any valve-related event was 94.9% at 1 year, 90.7% at 5 years, and 82.5% at 10 years. Conclusions-: Although longer follow-up of patients who undergo Ross operation is needed, the present series confirms that the autograft procedure is a valid option to treat aortic valve disease in selected patients. The nonreinforced full root technique and preoperative aortic regurgitation are predictors for autograft failure and warrant further consideration.

Long-term outcomes after autograft versus homograft aortic root replacement in adults with aortic valve disease: A randomised controlled trial (Article)

2010-08-01T00:00:00Z

The ideal substitute for aortic valve replacement in patients with aortic valve disease is not known. Our hypothesis was that the regulatory and adaptive properties of a living valve substitute could improve the long-term outcomes in patients. We therefore compared these outcomes after autograft aortic root replacement (Ross procedure) versus homograft aortic root replacement in adults. Male and female patients (<69 years) requiring aortic valve surgery were randomly assigned in a one-to-one ratio to receive an autograft or a homograft aortic root replacement in one centre in the UK. The random allocation sequence was computer generated. Treatment was not masked. The primary endpoint was survival of patients at 10 years after surgery. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN03530985. 228 patients were randomly assigned to receive an autograft or a homograft aortic root replacement. 12 patients were excluded because they were younger than 18 years; 108 in each group received the surgery they were assigned to and were analysed. There was one (<1) perioperative death in the autograft group versus three (3) in the homograft group (p=0·621). At 10 years, four patients died in the autograft group versus 15 in the homograft group. Actuarial survival at 10 years was 97 (SD 2) in the autograft group versus 83 (4) in the homograft group. Hazard ratio for death in the homograft group was 4·61 (95 CI 1·71-16·03; p=0·0060). Survival of patients in the autograft group was similar to that in an age-matched and sex-matched British population (96). Our findings support the hypothesis that a living valve implanted in the aortic position can significantly improve the long-term outcomes in patients. Funding Magdi Yacoub Institute.

Specific requirements for bloodless cardiopulmonary bypass in neonates and infants; A review (Article)

2010-07-01T00:00:00Z

A miniaturized cardiopulmonary bypass circuit enables the safe performance, in selected pediatric patients, of bloodless open heart surgery. As the latest survival rates in neonatal and infant cardiac surgery have become satisfactory, investigators have concentrated upon the improvement of existing procedures. Institutional guidelines and multidisciplinary efforts undertaken in the pre- and postoperative periods are of great importance, concerning bloodless CPB and should be seriously pursued by all involved caregivers. This review reflects upon the selective, most relevant requirements for success of asanguinous neonatal and infant CPB: acceptable level of hemodilution during the CPB, patient preoperative hematocrit value and volume of CPB circuit. We present an assessment of practical measures that were also adapted in our institution to achieve an asanguinous CPB for neonatal and infant patients.

Pulmonary autograft valve explants show typical degeneration (Article)

2010-06-01T00:00:00Z

Objectives: We sought to evaluate the microscopic characteristics of pulmonary autograft valve explants. Methods: Cell density and thickness of the autograft valve ventricularis were determined and compared with those of normal aortic and pulmonary valves (n = 11). Cellular phenotype and extracellular matrix involvement were assessed with immunohistochemistry. Collagen 3-dimensional architecture was studied by means of confocal microscopy. Results: The autograft valve exhibited characteristic thickening of the ventricularis compared with the normal aortic and pulmonary valves (137 vs 77 [P = .058] vs 37 μm [P = .002], respectively). Its cell number was increased compared with those of the normal aortic and pulmonary valves (396 vs 230 [P = .02] vs 303 [P = .083], respectively). Myofibroblasts and stressed endothelial cells, both of which were present in pulmonary autografts, were absent in control valves. The exclusive presence of matrix metalloproteinase 1 was an additional sign of extracellular matrix turnover. Apoptosis, elastinolysis, cell proliferation, and senescence were not expressed. Dense fibrosis of the autograft ventricularis with relatively well-aligned collagen fibers was observed with confocal microscopy. Conclusions: Fibrous hyperplasia of the ventricularis and cellular and extracellular matrix characteristics of active remodeling were a consistent finding in pulmonary autograft valve explants. The observations suggest a primary valve-related cause to be involved in pulmonary autograft valve failure.

The Ross operation in children. Results from the European Ross Registry [Die Ross-Operation bei Kindern. Ergebnisse aus dem Europäischen Ross-Register] (Article)

2010-04-01T00:00:00Z

Objectives: To determine the durability of autografts and homografts after Ross operations in children. Patients and methods: The data of 152 children <16 years were analyzed using the Cox proportional hazards model and hierarchical multilevel modeling. Results: Autograft regurgitation increased with sinotubular junction diameter (p=0.028). The homograft gradient increased within the first 2 years (4.2 mmHg/year, p<0.001). Freedom from autograft and homograft reintervention at 10 years was 95.5±2.7% and 79.6±6.1%, respectively. Longer follow-up time was a risk factor for autograft reintervention (p=0.036). Use of an aortic homograft was a risk factor for conduit reintervention (p=0.013). Conclusions: Reinterventions are necessary for autograft regurgitation and homograft stenosis. Increasing sinotubular junction diameters explain autograft regurgitation. Using pulmonary homografts delays the development of a homograft gradient.

Performance of the CryoValve* SG human decellularized pulmonary valve in 342 patients relative to the conventional CryoValve at a mean follow-up of four years (Article)

2010-02-01T00:00:00Z

Objective: This study compared clinical outcomes of patients receiving CryoValve SG decellularized pulmonary valves with those of patients receiving conventionally processed CryoValve pulmonary valves. Methods: All consecutive patients undergoing Ross procedures and right ventricular outflow tract reconstructions with SG valves at 7 institutions (February 2000-November 2005) were assessed retrospectively (193 Ross procedures, 149 right ventricular outflow tract reconstructions). Patient, procedural, and outcome data were compared with those from 1246 conventional implants (665 Ross procedures, 581 right ventricular outflow tract reconstructions). Hemodynamic function was assessed at latest follow-up. Results: Follow-up was complete for 99% in SG group and 94% in conventional group, with mean follow-ups of 4.0 years (range, 0-6.7 years) for SG and 3.7 years (range, 0-6.7 years) for conventional. Five-year cumulative survivals and freedoms from adverse events were comparable between SG and conventional valves. Among patients undergoing Ross procedures, peak gradient at last follow-up was lower with SG valves (P < .01); no difference was observed in the right ventricular outflow tract reconstruction population. Pulmonary insufficiency was significantly reduced with SG valves in patients undergoing both Ross procedures (P < .01) and right ventricular outflow tract reconstructions (P < .01). Valve type was not a significant predictor of valve-related failure in propensity-adjusted analysis of either procedure. Conclusions: CryoValve SG decellularized pulmonary valves have acceptable clinical outcomes and favorably compare with conventionally processed valves. Improved hemodynamic function observed with SG valves could signify improved long-term outcomes and may be due to the decreased antigenicity of these valves.

Late Outcomes Following Freestyle Versus Homograft Aortic Root Replacement. Results From a Prospective Randomized Trial (Article)

2010-01-26T00:00:00Z

Objectives: The aims of this study were to compare long-term results after homograft versus Freestyle (Medtronic Inc., Minneapolis, Minnesota) aortic root replacement. Background: The ideal substitute for aortic root replacement remains undetermined. Methods: Between 1997 and 2005, 166 patients (age 65 ± 8 years) undergoing total aortic root replacement were randomized to receive a homograft (n = 76) or a Freestyle bioprosthesis (n = 90). Six patients randomly assigned to homograft crossed over to Freestyle because of unavailability of suitably sized homografts. Median follow-up was 7.6 years (maximum 11 years; 1,035 patient-years). "Evolving" aortic valve dysfunction was defined as aortic regurgitation ≥2/4 and/or peak gradient >20 mm Hg. Results: Patient characteristics were comparable between groups. Concomitant procedures were performed in 44% and 47% of Freestyle and homograft patients, respectively (p = 0.5). Overall hospital mortality was 4.8% (1% for isolated root replacement). Eight-year survival was 80 ± 5% in the Freestyle group versus 77 ± 6% in the homograft group (p = 0.9). Freedom from need for reoperation at 8 years was significantly higher after Freestyle root replacement (100 ± 0% vs. 90 ± 5% after homograft replacement; p = 0.02). All reoperations were secondary to structural valve deterioration (n = 6). At last echocardiographic follow-up, actuarial freedom from evolving aortic valve dysfunction was 86 ± 5% for Freestyle bioprostheses versus 37 ± 7% for homografts (p < 0.001). Clinically, freedom from New York Heart Association functional class III to IV and freedom from valve-related complications were similar between groups (p = 0.7 and p = 0.9, respectively). Conclusions: In this patient group, late survival is similar after homograft versus Freestyle root replacement. However, Freestyle aortic root replacement is associated with significantly less progressive aortic valve dysfunction and a lower need for reoperations.

Relevance of colloid oncotic pressure regulation during neonatal and infant cardiopulmonary bypass: a prospective randomized study (Article)

2010-01-01T00:00:00Z

Objective: In neonatal and infant cardiac surgery with cardiopulmonary bypass (CPB), hemodilution with reduction of plasma albumin concentration and low colloid oncotic pressure (COP) are the main factors associated with tissue edema and postoperative weight gain. The aim of our study was to evaluate the influence of two different COP regulatory strategies on post-bypass body weight gain, fluid balance, and clinical outcomes. Methods: Seventy elective patients with body weight < 10 kg underwent first-time cardiac surgery with CPB and were randomized into two groups. The standard COP group received 0.5 g kg-1 of human albumin in the priming and, during CPB, albumin was added to maintain the COP > 15 mmHg. In the high COP group, albumin concentration in the priming was 5% and, during CPB, the COP was maintained above 18 mmHg. All patients were monitored before, during and until 24 h postoperatively. Data were collected on body weight gain, COP, albumin concentration, fluids transfusion, blood loss, urine production and laboratory results. Results: Patients' demographics and operative data were comparable. Although the high COP group had perioperatively significantly higher COP and albumin concentration than the standard COP group, no significant difference was found in the body weight gain. There were also no significant differences between the groups with respect to fluid balance, urine output and blood loss. However, the high COP group had significantly shorter postoperative duration of mechanical ventilation (10 h vs 14 h, p = 0.02) and lower plasma lactate concentration post operation (1.1 mmol l-1 vs 1.4 mmol l-1, p = 0.046). Conclusions: The COP regulatory strategy for neonatal and infant CPB, based upon the 5% concentration of albumin in the priming and a COP target of 18 mmHg during bypass, better preserves the plasma albumin concentration within the physiological range and stabilizes the colloid pressure than the standard strategy (0.5 g kg-1 albumin in the priming and bypass COP target at 15 mmHg). Nevertheless, only the lower postoperative plasma lactate concentration and the shorter duration of mechanical ventilation in the high COP group indicated the potential clinical benefit of this new strategy.

Surgical Treatment of Active Native Aortic Valve Endocarditis With Allografts and Mechanical Prostheses (Article)

2009-12-01T00:00:00Z

Background: Surgical intervention for persistent active native aortic valve endocarditis (NVE) remains challenging. We analyzed our combined experience with allografts and mechanical prostheses (MP) in NVE operations. Methods: Between 1980 and 2002, 138 patients (81% males) underwent aortic valve replacement for NVE in 2 centers (106 allografts; 32 MPs). Perioperative characteristics and early and late morbidity and mortality were analyzed. Results: Mean age was 47 years (range, 14 to 76 years), and 34% required emergency surgery. Abscess rate was 38% for allografts vs 18% for MPs. Concomitant mitral valve replacement was required in 38% MP patients and in 5% allograft patients. Hospital mortality was 8% (n = 11; p = 0.25): 10 allograft patients (9%) and 1 MP patient (3%). During a mean 8-year follow-up (range, 0 to 25 years) 33 patients died: 22 allograft (24%) and 11 MP patients (21%; p = 0.14). Survival at 15 years was 59% ± 6% for allograft patients and 66% ± 9% for MP patients (p = 0.68). Late recurrent endocarditis developed in 6 allograft patients and 1 MP patient (p = 0.29). Overall 15-year freedom from reoperation was 76% ± 9% for allografts and 93% ± 6% for MPs (p = 0.02). Conclusions: Mechanical prostheses have comparable rates of midterm survival and freedom from recurrent infection. However, this is in combination with extensive excision of destructive tissue in a specific patient subset. Allograft reoperation rates increase with time. The importance of the mechanical prosthesis in NVE might be established in the coming years.

How to assess risks of valve surgery: Quality, implementation and future of risk models (Article)

2009-12-01T00:00:00Z

Autograft reinforcement to preserve autograft function after the ross procedure: a report from the german-dutch ross registry. (Article)

2009-09-15T00:00:00Z

BACKGROUND: Autograft reinforcement interventions (R) during the Ross procedure are intended to preserve autograft function and improve durability. The aim of this study is to evaluate this hypothesis. METHODS AND RESULTS: 1335 adult patients (mean age:43.5+/-12.0 years) underwent a Ross procedure (subcoronary, SC, n=637; root replacement, Root, n=698). 592 patients received R of the annulus, sinotubular junction, or both. Regular clinical and echocardiographic follow-up was performed (mean:6.09+/-3.97, range:0.01 to 19.2 years). Longitudinal assessment of autograft function with time was performed using multilevel modeling techniques. The Root without R (Root-R) group was associated with a 6x increased reoperation rate compared to Root with R (Root+R), SC with R (SC+R), and without R (SC-R; 12.9% versus 2.3% versus 2.5%.versus 2.6%, respectively; P<0.001). SC and Root groups had similar rate of aortic regurgitation (AR) development over time. Root+R patients had no progression of AR, whereas Root-R had 6 times higher AR development compared to Root+R. In SC, R had no remarkable effect on the annual AR progression. The SC technique was associated with lower rates of autograft dilatation at all levels of the aortic root compared to the Root techniques. R did not influence autograft dilatation rates in the Root group. CONCLUSIONS: For the time period of the study surgical autograft stabilization techniques preserve autograft function and result in significantly lower reoperation rates. The nonreinforced Root was associated with significant adverse outcome. Therefore, surgical stabilization of the autograft is advisable to preserve long-term autograft function, especially in the Root Ross procedure.

Anatomical and functional assessment of single left internal mammary artery versus arterial T-grafts 12 years after surgery (Article)

2009-09-01T00:00:00Z

We determined whether ultrasonographic left internal mammary artery (LIMA) findings correspond with 64 multislice computed tomography (MSCT) in patients 12 years after coronary artery bypass grafting. We included 34 patients (63.2±9.2 years), 16 with conventional single LIMA (group I) and 18 arterial T-grafts (group II), in a cross-sectional study. Patients underwent transthoracic proximal LIMA ultrasonography at rest and during the Azoulay maneuver, transthoracic echocardiography of the left ventricle and 64-MSCT, 11.5±1.4 years postoperatively. MSCT scans showed three string sign LIMA grafts (19%) in group I and three distal string sign LIMA grafts (17%) and 16 occluded T-graft anastomoses (22%) in group II. LIMA diameters and areas are significantly larger in group II in the origin, 3.5±0.7 vs. 2.5±0.5 mm, P=0.00007 and 0.09±0.04 vs. 0.05±0.02 cm2, P=0.00019 and in the third intercostal space, 3.4±0.7 vs. 2.5±0.5 mm, P=0.00009 and 0.09±0.03 vs. 0.05±0.02 cm2, P=0.000047. Most ultrasonographic LIMA findings do not differ between the groups. Thus, proximal LIMA diameters and areas are significantly larger in T-grafts and ultrasonographic variables equalize between the groups at rest and during the Azoulay maneuver 12 years after surgery.

Neoaortic Root Diameters and Aortic Regurgitation in Children After the Ross Operation (Article)

2009-08-01T00:00:00Z

Background: For children who require aortic valve replacement, the Ross operation provides a unique advantage of growth potential of the pulmonary autograft in the aortic position. This study assessed the progression of autograft root diameters and its effect on aortic regurgitation (AR). Methods: Neoaortic echo dimensions from 48 children (<16 years) undergoing Ross operation who had follow-up echocardiograms before age 20 were analyzed (mean follow-up, 5.1 ± 3.3 years). Results: The mean age at the time of the Ross operation was 10.0 ± 4.3 years. Mean z values of the neoaortic annulus (1.5 ± 0.4), sinus (2.5 ± 0.4), and sinotubular junction (2.6 ± 0.9) when the autograft was implanted were significantly larger compared with normal values (p < 0.001, all). The mean z values significantly increased with follow-up at the level of the sinus (0.5 ± 0.1/year, p < 0.001) and the sinotubular junction (0.7 ± 0.2, p < 0.001), but not at the level of the annulus (0.1 ± 0.1, p = 0.59). AR increased with follow-up time (0.07 ± 0.02 grade/year, p < 0.001). AR increased with sinotubular junction diameter (p = 0.028), but there was not significant evidence of an association with annulus diameter (p = 0.25) or sinus diameter (p = 0.40). Conclusions: Children undergoing Ross operation have larger neoaortic root dimensions than healthy children. Growth of the annulus matches somatic growth. The diameters of the sinus and the sinotubular junction increase significantly relative to somatic growth. The latter may explain the development of AR.

Homograft Performance in Children After the Ross Operation (Article)

2009-08-01T00:00:00Z

Background: The Ross operation may be the ideal aortic valve replacement in pediatric patients. However, reoperations for replacement of the homograft in the pulmonary position are inevitable. This study determined influencing factors for the development of homograft stenosis and regurgitation in pediatric Ross patients. Methods: Follow-up echocardiograms of 116 children (86 boys) undergoing Ross operations at a mean age, 9.3 ± 4.9 years were analyzed using hierarchic multilevel modeling. Mean duration of the echocardiographic follow-up was 5.3 ± 4.2 years (609 patient-years, 398 examinations). Results: Median homograft diameter z value was 0.3 (range -2.2 to +7.3). Mean homograft pressure gradient at implantation was 5.0 mm Hg with a significant increase of 4.2 mm Hg/y (p < 0.001) within the first 2 years and a steady state thereafter. Older donor age was significantly associated with lower mean pressure gradient at implantation (p = 0.037). Larger z value had no significant influence on the annual increase of pressure gradient (p = 0.87). Mean grade of regurgitation at implantation was 0.9, without significant annual increase (0.02 grade/y, (p = = 0.32). Older recipient (p = 0.005) and donor age (p < 0.0001) were significantly associated with lower mean regurgitation at implantation. Larger z value was associated with a higher annual increase of regurgitation (p = 0.014). Conclusions: Relevant midterm homograft regurgitation is rare in children after the Ross operation. However, a significant annual increase occurs in the pressure gradient that cannot be influenced by larger graft size. Homograft oversizing may lead to a higher annual increase of regurgitation.

Seventeen years of adult congenital heart surgery: a single centre experience (Article)

2009-07-01T00:00:00Z

Objective: With a growing number of children with congenital heart disease (CHD) reaching adulthood, an extensive experience with cardiac surgery in adults with CHD is accumulating. To increase insight in this patient category we report our 17-year single centre experience including predictors for adverse outcome and EuroSCORE performance. Methods: Patients and operative characteristics of all consecutive adult CHD patients operated upon between January 1990 and January 2007 were collected. Categorisation was done according to the EACTS/STS congenital database. Early and late morbidity and mortality were assessed with follow-up extending up to 17 years. EuroSCORE performance was assessed. Results: Nine hundred and sixty-three procedures were performed in 830 patients (mean age 39.3 years, 50.3% male). A total of 49% were re-do procedures, frequent procedures were for left heart lesions (37%), right heart lesions (31%) and septal defects (8%). The 51% primary procedures largely consisted of less complex procedures but also included 1.4% of tetralogy of Fallot repairs, 4.1% of aortic coarctation repairs and 2.7% of Ebstein's disease repairs. Thirty-day mortality was 1.5% (n = 14); predicted mortality by logistic EuroSCORE was 4.6%. c-index was 0.61 (95% CI 0.46-0.75). Major complications such as tamponade requiring intervention occurred in 3.2%, postoperative bleeding requiring re-exploration in 7.1% and renal insufficiency requiring dialysis in 4 (0.4%). Pulmonary hypertension was a strong predictor for short-term mortality; impaired ventricular function and cyanosis for long-term mortality. Overall 17-year survival was 71% (95% CI 61%-82%). Eighty percent of patients were in NYHA class I at last follow-up, 17% in II, 3% in III, 0% in IV. Conclusions: Surgery in adult CHD patients can be performed with low operative mortality and good clinical outcome. EuroSCORE is not a good model for risk assessment in this group of patients.

Therapeutic decisions for patients with symptomatic severe aortic stenosis: room for improvement? (Article)

2009-06-01T00:00:00Z

Objective: Symptomatic severe aortic stenosis is an indication for aortic valve replacement. Some patients are denied intervention. This study provides insight into the proportion of conservatively treated patients and into the reasons why conservative treatment is chosen. Methods: Of a patient cohort presenting with severe aortic stenosis between 2004 and 2007, medical records were retrospectively analyzed. Only symptomatic patients (n = 179) were included. We studied their characteristics, treatment decisions, and survival. Results: Mean age was 71 years, 50% were male. During follow-up (mean 17 months, 99% complete) 76 (42%) patients were scheduled for surgical treatment (63 conventional valve replacement, 10 transcatheter, 1 heart transplantation, 2 waiting list) versus 101 (56%) who received medical treatment. Reasons for medical treatment were: perceived high operative risk (34%), symptoms regarded mild (19%), stenosis perceived non-severe (14%), and patient preference (9%). In 5% the decision was pending at the time of the analysis and in 20% the reason was other/unclear. Mean age of the surgical group was 68 years versus 73 years for medically treated patients (p = 0.004). Predicted mortality (EuroSCORE) was 7.8% versus 11.3% (p = 0.006). During follow-up 12 patients died in the surgical group (no 30-day operative mortality), versus 28 in the medical group. Two-year survival was 90% versus 69%. Conclusions: A large proportion (56%) of symptomatic patients does not undergo aortic valve replacement. Often operative risk is estimated (too) high or hemodynamic severity and symptomatic status are misclassified. Interdisciplinary team discussions between cardiologists and surgeons should be encouraged to optimize patient selection for surgery.

Risk factors for low colloid osmotic pressure during infant cardiopulmonary bypass with a colloidal prime (Article)

2009-05-01T00:00:00Z

Extensive variations of colloid osmotic pressure (COP) measured in the priming as well as during infant cardiopulmonary bypass motivated us to audit clinical and laboratory data to identify the risk factors for low COP at the end of bypass. Data of 73 consecutive infant patients with body weight <10 kg, who underwent elective, first time open-heart surgery between March 2005 and December 2006 were examined. The following variables were analyzed: COP, blood loss, transfusion requirements and hematological data. Univariate and multivariate analysis of risk factors for low COP (<15 mmHg) was performed. Forty-eight percent of patients had COP <15 mmHg at the end of bypass. Those patients had significantly lower COP before start of bypass, during, and at the end of the operation. Significant univariate predictors of low COP at the end of bypass were: lower patient weight; lower COP before start of bypass, lower priming COP and larger volume of cardioplegia received into the circulation. After multivariable analysis, lower patient COP before bypass remained the only significant predictor for low COP at the end of bypass. Pre-bypass crystalloid dilution during induction should be avoided, as this is the most important cause of low COP during the bypass. Priming COP and COP management strategy should be adapted to the individual patient demand.

Patient outcome after aortic valve replacement with a mechanical or biological prosthesis: Weighing lifetime anticoagulant-related event risk against reoperation risk (Article)

2009-04-01T00:00:00Z

Objective: Although the results of aortic valve replacement with different valve prostheses are well documented in terms of survival, the risks of (valve-related) events are less well explored. Methods: We used a dataset of 3934 patients who underwent aortic valve replacement with either a bioprosthesis (73%) or a mechanical prosthesis (27%) between 1982 and 2003 to simulate the outcome of patients after aortic valve replacement with either valve type. With the use of microsimulation, we compared total age and gender-specific life expectancy, event-free life expectancy, reoperation-free life expectancy, lifetime risks of reoperation, and valve-related events for both valve types. Results: The total follow-up was 26,467 patient-years. The mean follow-up was 6.1 years in the biological arm and 8.5 years in the mechanical arm. The mean age at implantation was 70 and 58 years for biological and mechanical prostheses, respectively, and the percentage of concomitant coronary artery bypass grafting was 47% and 28%, respectively. For a 60-year-old man, simulated life expectancy in years for biological versus mechanical prostheses was 11.9 versus 12.2, event-free life expectancy was 9.8 versus 9.3, and reoperation-free life expectancy was 10.5 versus 11.9. Lifetime risk of reoperation was 25% versus 3%. Lifetime risk of bleeding was 12% versus 41%. Conclusion: Even for patients aged 60 years, event-free life expectancy is better with a bioprosthesis. Although the chance of reoperation is higher, the lifetime risk of bleeding is lower compared with a mechanical prosthesis. Comparing lifetime event risks between different types of valve prostheses provides more insight into patient outcome after aortic valve replacement and aids patient selection and counseling.

The Ross procedure: A systematic review and meta-analysis (Article)

2009-01-20T00:00:00Z

Background - Reports on outcome after the Ross procedure are limited by small study size and show variable durability results. A systematic review of evidence on outcome after the Ross procedure may improve insight into outcome and potential determinants. Methods and Results - A systematic review of reports published from January 2000 to January 2008 on outcome after the Ross procedure was undertaken. Thirty-nine articles meeting the inclusion criteria were allocated to 3 categories: (1) consecutive series, (2) adult patient series, and (3) pediatric patient series. With the use of an inverse variance approach, pooled morbidity and mortality rates were obtained. Pooled early mortality for consecutive, adult, and pediatric patients series was 3.0% (95% confidence interval [CI], 1.8 to 4.9), 3.2% (95% CI, 1.5 to 6.6), and 4.2% (95% CI, 1.4 to 11.5). Autograft deterioration rates were 1.15% (95% CI, 1.06 to 2.06), 0.78% (95% CI, 0.43 to 1.40), and 1.38%/patient-year (95% CI, 0.68 to 2.80), respectively, and for right ventricular outflow tract conduit were 0.91% (95% CI, 0.56 to 1.47), 0.55% (95% CI, 0.26 to 1.17), and 1.60%/patient-year (95% CI, 0.84 to 3.05), respectively. For studies with mean patient age >18 years versus mean patient age ≤ 18 years, pooled autograft and right ventricular outflow tract deterioration rates were 1.14% (95% CI, 0.83 to 1.57) versus 1.69% (95% CI, 1.02 to 2.79) and 0.65% (95% CI, 0.41 to 1.02) versus 1.66%/patient-year (95% CI, 0.98 to 2.82), respectively. Conclusions - The Ross procedure provides satisfactory results for both children and young adults. Durability limitations become apparent by the end of the first postoperative decade, in particular in younger patients.

Blood dendritic cell levels and phenotypic characteristics in relation to etiology of end-stage heart failure: Implications for dilated cardiomyopathy (Article)

2009-01-09T00:00:00Z

Background: Dysregulation of dendritic cell (DC) mediated immune responses towards auto-antigens, is considered an important feature in the maintenance of experimentally induced heart failure (HF). In order to evaluate the role of blood DCs in cardiomyopathies of different origins, we examined myeloid (mDC) and plasmacytoid (pDC) subset levels and maturation characteristics, according to HF severity and etiology in humans. Methods: Absolute numbers of mDCs and pDCs in 12 New York Heart Association (NYHA) class-II, 28 NYHA class III-IV HF patients and 18 healthy controls, were studied by 4-colour whole blood flow cytometry. Results: End-stage (NYHA III-IV) HF patients had comparable circulating DC subset levels to NYHA-II patients and controls. However, within the NYHA III-IV group total DC levels in patients with non-ischemic dilated cardiomyopathy (DCM) were higher (P < 0.001) than in patients with coronary artery disease (CAD), hypertrophic cardiomyopathy (HCM) or other HF etiology. This was due to a significant increase of primarily mDCs (P < 0.0001) and to a lesser extent of pDCs (P < 0.05) in idiopathic DCM patients, independent of systolic or diastolic cardiac dysfunction. Maturation marker CD83 and lymphoid homing chemokine receptor CCR7 surface expression was enhanced only on mDCs, but not pDCs from DCM patients (P < 0.05), compared to patients with CAD, HCM or other underlying cardiac pathophysiology. Conclusions: Total blood DC levels in end-stage HF are elevated in patients with DCM. Whole blood DC characterisation may lead to new insights into the pathophysiology of idiopathic DCM in humans.

Invited commentary. Rheumatic heart disease: the quest for optimal screening. (Article)

2009-01-01T00:00:00Z

Reply to Paraskevas (Article)

2009-01-01T00:00:00Z

Is the Ross procedure really a Trojan horse: Reply (Article)

2008-09-01T00:00:00Z

Intraoperative cell salvage in infants undergoing elective cardiac surgery: a prospective trial (Article)

2008-08-01T00:00:00Z

Background: For a long time intraoperative cell salvage was considered not to be applicable in paediatric patients due to technical limitations. Recently, new autotransfusion devices with small volume centrifugal bowls and dedicated paediatric systems allow efficient blood salvage in small children. The purpose of this prospective non-randomised study was to determine the impact of intraoperative cell salvage on postoperative allogeneic blood products transfusion in infant patients undergoing cardiac surgery with cardiopulmonary bypass. Methods: Two consecutive cohorts (122 patients) were studied. The first cohort underwent procedures between January 2004 and July 2005 with only blood salvage from the residual volume. The second cohort consisted of patients operated on from August 2005 to December 2006, with additional use of intraoperative cell salvage. The following variables were analysed: peri- and postoperative blood loss, transfusion of homologous blood products and cell salvage product, haematological and coagulation data, measured before, during and after the operation. Results: Additional intraoperative cell salvage significantly enhanced the amount of cell saving product available for transfusion (183 ± 56 ml vs 152 ± 57 ml, p = 0.003) and significantly more patients in this group received the cell saving product postoperatively. Consequently, allogeneic blood transfusion was significantly reduced in volume as well as in frequency. We did not observe any adverse effects of intraoperative cell salvage. Conclusion: Intraoperative cell salvage, employed as an adjuvant technique to the residual volume salvage in infants undergoing first time cardiac surgery with cardiopulmonary bypass, was a safe and effective method to reduce postoperative allogeneic blood transfusion. Considering current cell salvage related expense and the cost reduction achieved by diminished allogeneic transfusion, intraoperative cell salvage in infants demonstrated no economic benefit.

Autograft or allograft aortic valve replacement in young adult patients with congenital aortic valve disease (Article)

2008-06-01T00:00:00Z

Aims: We analysed the outcome of young adults with congenital aortic valve disease who underwent allograft or autograft aortic valve or root replacement in our institution and evaluated whether there is a preference for either valve substitute. Methods and results: Between 1987 and 2007, 169 consecutive patients with congenital aortic valve disease aged 16-55, participating in our ongoing prospective follow-up study, underwent 63 autograft and 106 allograft aortic valve replacements (AVRs). Mean age was 35 years (SD 10.8), 71% were males. Aetiology was 71% bicuspid valve, 14% other congenital, and 15% BV endocarditis. Twenty-two percent underwent previous cardiac surgery; 11% had an ascending aorta aneurysm. Two patients died in hospital. During follow-up six more patients died and 45 patients required valve-related re-operations. Thirteen-year survival was 97% for autograft and 93% for allograft recipients, 13 year freedom from valve-related re-operation was 63% for autograft and 69% for allograft patients. Conclusion: In patients with congenital aortic valve disease, autograft and allograft AVR show comparable satisfactory early and long-term results, with the increasing re-operation risk in the second decade after operation remaining a major concern.

Optimum management of elderly patients with calcified aortic stenosis (Article)

2008-04-01T00:00:00Z

Increased life-expectancy has led to a growing elderly population frequently presenting with aortic stenosis. This review focuses on the pathogenesis of calcific aortic stenosis, diagnosis and possible ways to halt the progression to severe symptomatic aortic stenosis, methods of assessing symptoms and severity, and modalities and timing of aortic valve replacement. At present the treatment of aortic stenosis for the majority of patients is surgical, and any patient with symptomatic severe aortic stenosis should be considered for aortic valve replacement. This article also discusses the role of emerging techniques of closed heart valve implantation either transfemoral or transapical, and which patients might be candidates for these new approaches to the treatment of aortic stenosis in the elderly population.

Measuring Follow-Up Completeness (Article)

2008-04-01T00:00:00Z

Completeness of follow-up is often used as a measure of the quality of follow-up, but the method used to compute it is often not declared. An ideal measure should be based on follow-up years instead of patients. Clark, Altman, and De Stavola proposed such a measure, called "C", which is the percentage of the maximum possible follow-up years, as of a given date, that has actually been accounted for or observed. However, such a measure will underestimate the true completeness, because the denominator (maximum possible follow-up years) does not account for unobserved patient deaths occurring before that date, and therefore, it is realistically unachievable. We propose a modification, C*, of Clark's C, which accounts for the effect of unobserved patient deaths in attenuating the maximum potential follow-up, and thus gives a higher percentage for achieved follow-up completeness. We validated this theoretical improvement by comparing the values of C and C* computed for our long-term coronary artery bypass graft patients to the true completeness, which was obtained by using the National Death Index to complete our missing follow-up data. Using Clark's C, the follow-up completeness was 80.4% and using our C* it is 84.5%, whereas the true follow-up completeness based on National Death Index information was 85.0%.

Do We Need Separate Risk Stratification Models for Hospital Mortality After Heart Valve Surgery? (Article)

2008-03-01T00:00:00Z

Background: The EuroSCORE (European System for Cardiac Operative Risk Evaluation) is often used to benchmark and predict hospital mortality after cardiac surgery. Based mainly upon coronary surgery patients, EuroSCORE may not be optimal for valve surgery patients. We evaluated the New York (NY) State dedicated valve surgery models and compared their performance to the EuroSCORE model. Methods: Required model variables were collected prospectively for all patients, followed by calculation of predictive mortality rates using the logistic and additive EuroSCORE, the logistic and additive NY State models for valve surgery without concomitant coronary surgery (isolated valve surgery) and the logistic and additive NY State models for combined valve and coronary surgery. Results: Observed mortality was 2.8% (25 of 904) for isolated valve surgery and 6.8% (27 of 395) for valve plus coronary surgery. Logistic NY State and EuroSCORE expected mortality for isolated valve surgery was respectively 3.0% and 6.1%, and for valve plus coronary surgery 5.9% and 7.8%. The logistic NY State model for isolated valve surgery showed better discrimination (c-index 0.86 versus 0.76) and calibration than the logistic EuroSCORE. Discriminatory power for the logistic NY State model for valve plus coronary surgery was comparable to the logistic EuroSCORE (c-index 0.74 versus 0.72), as was calibration. Conclusions: Our results suggest that dedicated risk models for valve surgery may be useful to provide more valid estimates of hospital mortality after heart valve surgery. Further exploration is needed to demonstrate general applicability of our results and assess the possible additional value of separate models for isolated valve surgery and valve plus coronary artery surgery, or aortic and mitral valve surgery, or both.

Reporting "actual freedom" should not be banned (Article)

2008-02-01T00:00:00Z

Low molecular starch versus gelatin plasma expander during CPB: Does it make a difference? (Article)

2007-12-01T00:00:00Z

Background: Non-protein plasma expanders carry a risk of potentially severe allergic reactions. As prime for cardiopulmonary bypass, we routinely use a gelatin plasma expander. Plasma expanding during anesthesia is achieved with high molecular starch (200/0.5 kDalton) in combination with Ringer Lactate solution (RL) and in the Intensive Care Unit (ICU) with a low molecular starch (130/0.4 kDalton). We evaluated the feasibility of low molecular starch in combination with RL (group LMSRL) versus gelatin plasma expanding (group GPE) for priming CPB circuits in patients undergoing cardiac surgery in a randomized prospective trial. Methods: One hundred and eighty adults who underwent primary valve or coronary artery bypass graft (CABG) surgery were equally stratified into 3 series of 60 patients with the routinely used oxygenators; Capiox RX-25, CML Duo and Quadrox-D. Then they were randomised by drawing lots and allocated into the LMSRL or GPE groups. We compared hematocrit, hemoglobin, platelet count, activated clotting time (ACT), lactate and colloid osmotic pressure (COP), blood loss, transfusion need, urine production and ICU stay. In addition, we monitored the average trans-oxygenator fluid resistance (AFR) for each type of oxygenator. Results: The COP is significantly lower in the LMSRL group (20 mmHg ± 0.2 versus 18 mmHg ± 0.2, p < 0.0001); as was the total use of plasma expanders (3846 ml ± 98 versus 3059 ml ± 77, p <0.001). All other parameters were not significantly different. When comparing the observed AFR for the three types of oxygenators, a lower AFR in the LMSRL group (p < 0.02) was noted for the Capiox RX-25®. Conclusions: This study shows a lower need for plasma expanders in patients who receive only starch plasma expanders. Further, we noted a lower COP in the LMSRL group, but since the mean COP was > 17 ± 0.2 mmHg, this cannot be considered of clinical importance. In conclusion, our study result supports the use of low molecular starch as a good alternative choice for priming CPB.

Congenital aortic stenosis in adults: Rate of progression and predictors of clinical outcome (Article)

2007-11-30T00:00:00Z

Background: Little data are available on the natural history of young adults with congenital valvular aortic stenosis (AS). The aim of the present study was to determine the progression rate of AS in young adults, and to identify predictors of stenosis progression and outcome. Methods: Retrospective study of all patients seen at a single centre diagnosed with congenital AS (≥ 2.5 m/s) between 1992 and 2005, excluding patients with severe aortic regurgitation. The slope of the regression of the aortic jet velocity on the time elapsed since the baseline study was used to define the rate of progression of stenosis. Results: A total of 84 adults (mean age, 23.5 ± 7.9 years) were studied who had at least two echocardiograms > 1 year (5.6 ± 2.6 years) apart. The annual progression of aortic jet velocity was 0.09 ± 0.15 m/s per year. Multivariable linear regression analysis identified older age (p < 0.001) as an independent predictor of faster haemodynamic progression. During the follow-up period of 7.7 ± 2.7 years, no patient died and 35 patients (42%) underwent aortic valve intervention. By multivariable Cox regression analysis, severe AS (≥ 4.0 m/s) and rapid progression of aortic jet velocity (≥ 0.2 m/s/year) were independent predictors of intervention. Cumulative intervention-free survival for patients with severe AS was 78 ± 8% at 3 years and 48 ± 10% at 5 years versus respectively 98 ± 2% and 96 ± 3% for patients with mild-to-moderate AS (log-rank: p < 0.001). Conclusions: Progression of congenital AS was relatively low in young adults compared to elderly with degenerative AS. Older age was associated with more rapid progression.

Usefulness of microsimulation to translate valve performance into patient outcome: Patient prognosis after aortic valve replacement with the Carpentier-Edwards supra-annular valve (Article)

2007-09-01T00:00:00Z

Objective: Numerous reports have been published documenting the results of aortic valve replacement. It is often not easy to translate these outcomes involving the condition of the valve into the actual consequences for the patient. We previously developed an alternative method to study outcome after aortic valve replacement that allows direct estimation of patient outcome after aortic valve replacement: microsimulation modeling. The goal of this article is to provide insight into microsimulation methodology and to give an overview of the advantages and disadvantages of simulation methods (in particular microsimulation) in comparison with standard methods of outcome analysis. Methods: By using a primary dataset containing 1847 patients and 14,429 patient-years, advantages and disadvantages of standard methods of outcome analysis are discussed, and the potential role of microsimulation is illustrated by means of a step-by-step explanation of building, testing, and using such a model. Results: Total life expectancy, event-free life expectancy, and reoperation-free life expectancy for a 65-year-old male patient were 10.6 years, 9.2 years, and 9.8 years, respectively. Lifetime risk of reoperation due to structural valve deterioration was 13.3%. Conclusions: Microsimulation is capable of providing accurate estimates of age-related life expectancy and lifetime risk of reoperation for patients who underwent aortic valve replacement with the Carpentier-Edwards supra-annular valve. It provides a useful tool to facilitate and optimize the choice for a specific heart valve prosthesis in a particular patient.

The Ross operation: A Trojan horse? (Article)

2007-08-01T00:00:00Z

Aims: The Ross operation is the operation of choice for children who require aortic valve replacement (AVR) and may also provide a good option in selected adult patients. Although the autograft does not require anticoagulation and has a superior haemodynamic profile, concern regarding autograft and allograft longevity has risen. In this light, we report the 13-year results of our prospective autograft cohort study. Methods and results: Between 1988 and 2005, 146 consecutive patients underwent AVR with a pulmonary autograft at Erasmus Medical Center Rotterdam. Mean age was 22 years (SD 13; range 4 months-52 years), 66% were male. Hospital mortality was 2.7% (N = 4); during follow-up four more patients died. Thirteen-year survival was 94 ± 2%. Over time, 22 patients required autograft reoperation for progressive neo-aortic root dilatation. In addition, eight patients required allograft reoperation. Freedom from autograft reoperation at 13 years was 69 ± 7%. Freedom from allograft reoperation for structural failure at 13 years was 87 ± 5%. Risk factors for autograft reoperation were previous AVR and adult patient age. Conclusion: Although survival of the Rotterdam autograft cohort is excellent, over time a worrisome increase in reoperation rate is observed. Given the progressive autograft dilatation, careful follow-up of these patients is warranted in the second decade after operation.

Effects of cardiopulmonary bypass circuit reduction and residual volume salvage on allogeneic transfusion requirements in infants undergoing cardiac surgery (Article)

2007-06-01T00:00:00Z

Cardiopulmonary bypass in children may cause severe hemodilution and can lead to excessive perioperative blood loss and high transfusion requirements. Minimization of cardiopulmonary bypass circuit and salvage of red blood cells from the residual volume after the procedure are widely utilized to reduce allogeneic transfusion. We evaluated the effectiveness of those measures introduced in infant cardiac surgery in our institution. This retrospective observational study included 148 consecutive infants between 1 and 12 months of age, with a body weight <10 kg, who underwent an elective cardiac operation between 1997 and 2005. Patients were divided into three groups defined by the circuit prime volume; 700 ml (Group 1), 450 ml (Group 2) and 330 ml (Group 3). In Group 1 residual volume after perfusion was discarded and in Groups 2 and 3 was processed in a cell saving device. Analyzed variables were: perioperative blood loss, transfusion of homologous blood products and cell salvage product, and hematology data. Reduction of the circuit volume significantly diminished use of red blood cell concentrates from 1.6 units to 0.8 units (P<0.0001), and fresh frozen plasma from 1.3 units to 0.4 units (P<0.0001). Utilization of the cell salvage product reduced significantly (P=0.023) the postoperative need for homologous blood transfusion. Therefore, both measures proved to be effective in reducing homologous blood transfusion in infant cardiac surgery.

Actual and Actuarial Probabilities of Competing Risks: Apples and Lemons (Article)

2007-05-01T00:00:00Z

The probability of a type of failure that is not inevitable, but can be precluded by other events such as death, is given by the cumulative incidence function. In cardiac research articles, it has become known as the actual probability, in contrast to the actuarial methods of estimation, usually implemented by the Kaplan-Meier (KM) estimate. Unlike cumulative incidence, KM attempts to predict what the latent failure probability would be if death were eliminated. To do this, the KM method assumes that the risk of dying and the risk of failure are independent. But this assumption is not true for many cardiac applications in which the risks of failure and death are negatively correlated (ie, patients with a higher risk of dying have a lower risk of failure, and patients with a lower risk of death have a higher risk of failure, which is a condition called informative censoring). Recent editorials in two cardiac journals have promoted the use of the KM method (actuarial estimate) for competing risk events (specifically for heart valve performance) and criticized the use of the cumulative incidence (actual) estimates. This report has two aims: to explain the difference between these two estimates and to show why the KM is generally not appropriate. In the process we will rely on alternative representations of the KM estimator (using redistribution to the right and inverse probability weighting) to explain the difference between the two estimates and to show how it may be possible to adjust KM to overcome the informative censoring.

Allografts for aortic valve or root replacement: insights from an 18-year single-center prospective follow-up study (Article)

2007-05-01T00:00:00Z

Objective: Whether allografts are the biological valve of choice for AVR in non-elderly patients remains a topic of debate. In this light we analyzed our ongoing prospective allograft AVR cohort and compared allograft durability with other biological aortic valve substitutes. Methods: Between April 1987 and October 2005, 336 patients underwent 346 allograft AVRs (95 subcoronary, 251 root replacement). Patient and perioperative characteristics, cumulative survival, freedom from reoperation, and valve-related events were analyzed. Using microsimulation, for adult patients, age-matched actual freedom from allograft reoperation was compared to porcine and pericardial bioprostheses. Results: Mean age was 45 years (range 1 month to 83 years); 72% were males. Etiology was mainly endocarditis 32% (active 22%), congenital 31%, degenerative 9%, and aneurysm/dissection 12%. Twenty-seven percent underwent prior cardiac surgery. Hospital mortality was 5.5% (N = 19). During follow-up (mean 7.4 years, maximum 18.5 years, 98% complete), 54 patients died; there were 57 valve-related reoperations (3 early technical, 11 non-structural, 39 structural valve deterioration (SVD), 4 endocarditis), 5 cerebrovascular accidents, 1 fatal bleeding, 8 endocarditis. Twelve-year cumulative survival was 71% (SE 3), freedom from reoperation for SVD 77% (SE 4); younger patient age was associated with increased SVD rates. Actual risk of allograft reoperation was comparable to porcine and pericardial bioprostheses in a simulated age-matched population. Conclusions: The use of allografts for AVR is associated with low occurrence rates of most valve-related events, but over time the risk of SVD increases, comparable to stented xenografts. It remains in our institute the preferred valve substitute only for patients with active aortic root endocarditis and for patients in whom anticoagulation should be avoided.

Dissection of a dilated autograft root (Article)

2007-03-01T00:00:00Z

The effect of open lung ventilation on right ventricular and left ventricular function in lung-lavaged pigs (Article)

2006-01-01T00:00:00Z

INTRODUCTION: Ventilation according to the open lung concept (OLC) consists of recruitment maneuvers, followed by low tidal volume and high positive end-expiratory pressure, aiming at minimizing atelectasis. The minimization of atelectasis reduces the right ventricular (RV) afterload, but the increased intrathoracic pressures used by OLC ventilation could increase the RV afterload. We hypothesize that when atelectasis is minimized by OLC ventilation, cardiac function is not affected despite the higher mean airway pressure. METHODS: After repeated lung lavage, each pig (n = 10) was conventionally ventilated and was ventilated according to OLC in a randomized cross-over setting. Conventional mechanical ventilation (CMV) consisted of volume-controlled ventilation with 5 cmH2O positive end-expiratory pressure and a tidal volume of 8-10 ml/kg. No recruitment maneuvers were performed. During OLC ventilation, recruitment maneuvers were applied until PaO2/FiO2 > 60 kPa. The peak inspiratory pressure was set to obtain a tidal volume of 6-8 ml/kg. The cardiac output (CO), the RV preload, the contractility and the afterload were measured with a volumetric pulmonary artery catheter. A high-resolution computed tomography scan measured the whole lung density and left ventricular (LV) volumes. RESULTS: The RV end-systolic pressure-volume relationship, representing RV afterload, during steady-state OLC ventilation (2.7 +/- 1.2 mmHg/ml) was not significantly different compared with CMV (3.6 +/- 2.5 mmHg/ml). Pulmonary vascular resistance (OLC, 137 +/- 49 dynes/s/cm5 versus CMV, 130 +/- 34 dynes/s/cm5) was comparable between groups. OLC led to a significantly lower amount of atelectasis (13 +/- 2% of the lung area) compared with CMV (52 +/- 3% of the lung area). Atelectasis was not correlated with pulmonary vascular resistance or end-systolic pressure-volume relationship.The LV contractility and afterload during OLC was not significantly different compared with CMV. Compared with baseline, the LV end-diastolic volume (66 +/- 4 ml) decreased significantly during OLC (56 +/- 5 ml) ventilation and not during CMV (61 +/- 3 ml). Also, CO was significantly lower during OLC ventilation (OLC, 4.1 +/- 0.3 l/minute versus CMV, 4.9 +/- 0.3 l/minute). CONCLUSION: In this experimental study, OLC resulted in significantly improved lung aeration. Despite the use of elevated airway pressures, no evidence was found for a negative effect of OLC on RV afterload or LV afterload, which might be associated with a loss of hypoxic pulmonary vasoconstriction due to alveolar recruitment. The reductions in the CO and in the mean pulmonary artery pressure were consequences of a reduced preload.

The impact of the introduction of drug-eluting stents on the clinical practice of surgical and percutaneous treatment of coronary artery disease. (Article)

2005-04-01T00:00:00Z

AIMS: Sirolimus-eluting stents (SES) have recently been shown to reduce restenosis in selected patients. The impact of this new stent on the use of coronary bypass graft (CABG) surgery or percutaneous coronary intervention (PCI) in clinical practice is yet unknown. Therefore, we investigated the impact of SES on the clinical practice of CABG and PCI in a series of unselected consecutive patients. METHODS AND RESULTS: Between April and October 2002, a policy of SES implantation for all procedures has been instituted in our hospital. In total, 798 patients were referred to PCI and 275 to CABG (SES group). A control group was composed of all interventions (806 PCI and 314 CABG) performed during the preceding 6 months (pre-SES). The main outcome was the occurrence of major adverse cardiac events (MACE) at 15 months. In the SES era, a significant shift was noted in the PCI group towards more multi-vessel stenting (28 vs. 24%; P<0.05), more bifurcation stenting (18 vs. 7%; P<0.0001), and the use of more stents (1.9 vs. 1.5; P<0.05). In the PCI elective patients, a shift was noted towards more three-vessel disease (pre-SES: 16% vs. SES: 23%; P=0.02). Furthermore, we observed a shift in the CABG group towards more impaired LV function (pre-SES: 34% vs. SES: 41%; P=0.02) and towards more three-vessel disease (pre-SES: 67% vs. SES: 75%; P=0.03). Overall, the cumulative MACE percentages at 1 year after coronary revascularization (PCI and CABG combined) decreased from 16.8 to 13.8% (P=0.03). The cumulative MACE percentages in the pure SES group and the pre-SES bare metal stent group at 12 months were 15.6 and 19.8%, respectively (P<0.01). CONCLUSION: The introduction of the SES has certainly had an impact on the treatment strategy of coronary artery disease (CAD). Increased use of these stents allows more complex coronary anatomy to be treated by PCI, and results in lower repeat revascularization rates.

Comparison of outcomes after aortic valve replacement with a mechanical valve or a bioprosthesis using microsimulation (Article)

2004-01-01T00:00:00Z

BACKGROUND: Mechanical valves and bioprostheses are widely used for aortic valve replacement. Though previous randomised studies indicate that there is no important difference in outcome after implantation with either type of valve, knowledge of outcomes after aortic valve replacement is incomplete. OBJECTIVE: To predict age and sex specific outcomes of patients after aortic valve replacement with bileaflet mechanical valves and stented porcine bioprostheses, and to provide evidence based support for the choice of prosthesis. METHODS: Meta-analysis of published results of primary aortic valve replacement with bileaflet mechanical prostheses (nine reports, 4274 patients, and 25,726 patient-years) and stented porcine bioprostheses (13 reports, 9007 patients, and 54,151 patient-years) was used to estimate the annual risks of postoperative valve related events and their outcomes. These estimates were entered into a microsimulation model, which was employed to calculate age and sex specific outcomes after aortic valve replacement. RESULTS: Life expectancy (LE) and event-free life expectancy (EFLE) for a 65 year old man after implantation with a mechanical valve or a bioprosthesis were 10.4 and 10.7 years and 7.7 and 8.4 years, respectively. The lifetime risk of at least one valve related event for a mechanical valve was 48%, and for a bioprosthesis, 44%. For LE and EFLE, the age crossover point between the two valve types was 59 and 60 years, respectively. CONCLUSIONS: Meta-analysis based microsimulation provides insight into the long term outcome after aortic valve replacement and suggests that the currently recommended age threshold for implanting a bioprosthesis could be lowered further.

Prognosis after Autograft and Allograft Aortic Root Replacement. Evidence-based Estimates using Meta-analysis and Microsimulation. (Doctoral Thesis)

2002-05-29T00:00:00Z

The goal of this thesis was to develop an objective and valid methodology to support the choice for a particular aortic valve substitute in the individual patient, with a primary focus on autografts and allografts. This includes the important question: Can patient-specific recommendations be made with regard to the preferred valve substitute for patients requiring aortic valve replacement, based on the methodology described in this thesis? This question will be discussed by: (1) Commenting on the current clinical evidence on outcome after aortic root replacement with autografts and allografts, (2) Critically evaluating the methods of meta-analysis and microsimulation with regard to their ability to predict outcome after aortic valve replacement, (3) Comparing calculated outcome after autograft versus allograft aortic root replacement, and versus other valve substitutes, and finally to actual situations. In conclusion, clinical experience with autograft and allograft aortic root replacement turned out to be limited, both with regard to number of patients and duration of follow-up. Meta-analysis and microsimulation provide an objective and flexible tool to overcome these limitations and allow calculations of long-term prognosis after autograft and allograft aortic root replacement based on current limited evidence. Using this methodology, detailed information can be obtained on the determinants of prognosis, providing improved insight into outcome after autograft and allograft aortic root replacement. However, both meta-analysis and microsimulation have their limitations and the output of the microsimulation model strongly depends on the quality of the input and the assumptions of the model. Continuous refinement and updating of the microsimulation model are therefore necessary to provide objective and valid estimates of outcome after aortic valve replacement in the future. Furthermore, education of clinicians on the methodology of microsimulation is essential for successful application in clinical practice. An internet application of the model should become available in the near future for easy access use by clinicians.

Human tissue valves in aortic position: determinants of reoperation and valve regurgitation (Article)

2001-01-01T00:00:00Z

BACKGROUND: Human tissue valves for aortic valve replacement have a limited durability that is influenced by interrelated determinants. Hierarchical linear modeling was used to analyze the relation between these determinants of durability and valve regurgitation measured by serial echocardiography. METHODS AND RESULTS: In adult patients, 218 cryopreserved aortic allografts were implanted with the subcoronary (85) or the root replacement technique (133), and 81 patients had root replacement with a pulmonary autograft. Mean follow-up was 4.2 years (SD 2.7; range, 0 to 10.5). Patient age, operator experience with subcoronary implantation, and allograft diameter were independent predictors for reoperation. With repeated color Doppler echocardiography, the severity of aortic regurgitation was assessed by the jet length method and the jet diameter ratio. Multilevel hierarchical linear modeling was used to estimate initial aortic regurgitation (intercept), its change over time (slope), and the effect of 11 potential determinants of durability on aortic regurgitation. With the jet length method, the intercept was 0.94 grade and the slope was 0.11 grade per year. With the jet diameter ratio, the intercept was 0.34 and the annual increase was 0.01. Subcoronary implanted valves had more initial aortic regurgitation, but progression of aortic valve regurgitation did not differ from root replacement. At midterm follow-up, recipient age <40 years was the only independent predictor of aortic regurgitation. CONCLUSIONS: Subcoronary implantation has a learning curve, resulting in more initial aortic regurgitation and early reoperation compared with root replacement. In both techniques, progression of aortic regurgitation over time is small but accelerated in young adults.

Prognosis after aortic valve replacement with a bioprosthesis: predictions based on meta-analysis and microsimulation (Article)

2001-01-01T00:00:00Z

BACKGROUND: Bioprostheses are widely used as an aortic valve substitute, but knowledge about prognosis is still incomplete. The purpose of this study was to provide insight into the age-related life expectancy and actual risks of reoperation and valve-related events of patients after aortic valve replacement with a porcine bioprosthesis. METHODS AND RESULTS: We conducted a meta-analysis of 9 selected reports on stented porcine bioprostheses, including 5837 patients with a total follow-up of 31 874 patient-years. The annual rates of valve thrombosis, thromboembolism, hemorrhage, and nonstructural dysfunction were 0.03%, 0.87%, 0.38%, and 0.38%, respectively. The annual rate of endocarditis was estimated at 0.68% for >6 months of implantation and was 5 times as high during the first 6 months. Structural valve deterioration was described with a Weibull model that incorporated lower risks for older patients. These estimates were used to parameterize, calibrate, and validate a mathematical microsimulation model. The model was used to predict life expectancy and actual risks of reoperation and valve-related events after implantation for patients of different ages. For a 65-year-old male, these figures were 11.3 years, 28%, and 47%, respectively. CONCLUSIONS: The combination of meta-analysis with microsimulation enabled a detailed insight into the prognosis after aortic valve replacement with a bioprosthesis for patients of different ages. This information will be useful for patient counseling and clinical decision making. It also could serve as a baseline for the evaluation of newer valve types.