http://repub.eur.nl/res/aut/986/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/37746/ 2012-11-14T00:00:00Z Thoracic aortic disease is an infrequently encountered condition of which the true prevalence and incidence is hard to establish. New thoracic aortic aneurysms are estimated to be present in 5-16/100.000 inhabitants in the USA and Sweden and seem to increase in prevalence. Probably this increase is largely due to improved diagnostics and ascertainment. In the USA aortic aneurysms were 19th in rank in the 2007 mortality statistics and constituted 0.5% of all deaths. In the Netherlands 1302 people were registered as having died due to aneurysms and dissections of the aorta in 2010. This is approximately 2 deaths per day and represents 1% of all mortality. In this introduction we will discuss the normal anatomy of the aorta, aortic pathology, surgical therapy of aortic diseases and the aims and outline of the thesis. http://repub.eur.nl/res/pub/37728/ 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. http://repub.eur.nl/res/pub/35039/ 2012-01-01T00:00:00Z Background: Aneurysmseosteoarthritis syndrome (AOS) is a new autosomal dominant syndromic form of thoracic aortic aneurysms and dissections characterised by the presence of arterial aneurysms and tortuosity, mild craniofacial, skeletal and cutaneous anomalies, and early-onset osteoarthritis. AOS is caused by mutations in the SMAD3 gene. Methods: A cohort of 393 patients with aneurysms without mutation in FBN1, TGFBR1 and TGFBR2 was screened for mutations in SMAD3. The patients originated from The Netherlands, Belgium, Switzerland and USA. The clinical phenotype in a total of 45 patients from eight different AOS families with eight different SMAD3 mutations is described. In all patients with a SMAD3 mutation, clinical records were reviewed and extensive genetic, cardiovascular and orthopaedic examinations were performed. Results Five novel SMAD3 mutations (one nonsense, two missense and two frame-shift mutations) were identified in five new AOS families. A follow-up description of the three families with a SMAD3 mutation previously described by the authors was included. In the majority of patients, early-onset joint abnormalities, including osteoarthritis and osteochondritis dissecans, were the initial symptom for which medical advice was sought. Cardiovascular abnormalities were present in almost 90% of patients, and involved mainly aortic aneurysms and dissections. Aneurysms and tortuosity were found in the aorta and other arteries throughout the body, including intracranial arteries. Of the patients who first presented with joint abnormalities, 20% died suddenly from aortic dissection. The presence of mild craniofacial abnormalities including hypertelorism and abnormal uvula may aid the recognition of this syndrome. Conclusion: The authors provide further insight into the phenotype of AOS with SMAD3 mutations, and present recommendations for a clinical work-up. http://repub.eur.nl/res/pub/37647/ 2012-01-01T00:00:00Z http://repub.eur.nl/res/pub/25666/ 2011-08-16T00:00:00Z This paper develops a two-stage planning procedure for master planning of elective and emergency patients while allocating at best the available hospital resources. Four types of resources are considered: operating theatre, beds in the medium and in the intensive care units, and nursing hours in the intensive care unit. A tactical plan is obtained by minimizing the deviations of the resources consumption to the target levels of resources utilization, following a goal programming approach. The MIP formulation to get this tactical plan is specifically designed to account for emergency care since it allows for the reservation of some capacity for emergency patients and possible capacity excess. To deal with the deviation between actually arriving elective patients and the average number of patients on which the tactical plan is based, we consider the possibility of planning a higher number of patients than the average to create operating slots in the tactical plan (slack planning). These operating slots are then filled in the operational plan following several flexibility rules. We consider three options for slack planning that lead to three different tactical plans on which we apply three flexibility rules to get finally nine alternative weekly schedules of elective patients. We then develop an algorithm to modify this schedule on a daily basis so as to account for emergency patients' arrivals. Scheduled elective patients may be cancelled and emergency patients may be sent to other hospitals. Cancellation rules for both types of patients rely on the possibility to exceed the available capacities. Several performance indicators are defined to assess patient service and hospital efficiency. Simulation results show a trade-off between hospital efficiency and patient service. http://repub.eur.nl/res/pub/26058/ 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. http://repub.eur.nl/res/pub/21751/ 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. http://repub.eur.nl/res/pub/24283/ 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. http://repub.eur.nl/res/pub/27008/ 2009-01-26T00:00:00Z A patient presented with palpitations at the emergency department 3 days after a percutaneous coronary intervention complicated by dissection of the left anterior descending and circumflex coronary arteries. Physical examination revealed a high pulse rate and low blood pressure and the electrocardiogram demonstrated atrioventricular nodal re-entry tachycardia. This arrhythmia was eventually terminated by electrical cardioversion. Echocardiography demonstrated moderate aortic regurgitation and subsequent computed tomography showed a large Stanford type A aortic dissection. The patient was successfully operated and discharged 10 days after surgery. http://repub.eur.nl/res/pub/29443/ 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. http://repub.eur.nl/res/pub/14707/ 2008-01-01T00:00:00Z Cardiothoracic surgery planning involves different resources such as operating theatre time, beds, IC beds and nursing staff. In the daily practice of the Thorax Centre case study setting, the planning focuses on optimal use of operating theatre time, though the performance of the Thorax Centre as a whole is often more limited by other resources. For operating theatres a master surgical schedule is used to allocate operating theatre resources at tactical level for a longer period. Operational schedules at weekly level are derived from this master schedule. Within cardiothoracic surgery different categories of patients can be distinguished based on their requirement of resources. The mix of patients operated is, therefore, an important decision variable for the Thorax Centre to manage the use of these resources. In this paper we will consider the planning problem at the tactical level to generate a master surgical schedule that realises a given target of patient throughput and optimises an objective function for the utilisation of resources. The problem can be mathematically approached by mixed integer linear programming, which we already demonstrated in a previous paper. The specific topic of the current paper is to investigate the influence of using a stochastic instead of a deterministic length of stay. We will discuss the new mathematical model developed for this planning problem. The results obtained by the model indicate that we can generate master surgical schedules with a better performance on target utilization levels of resources by considering the stochastic length of stay. © 2008 The Author(s). http://repub.eur.nl/res/pub/35749/ 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. http://repub.eur.nl/res/pub/36657/ 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. http://repub.eur.nl/res/pub/9241/ 2000-01-01T00:00:00Z