http://repub.eur.nl/res/aut/2876/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/33679/ 2011-06-01T00:00:00Z AimsComparison of magnetic guidewire navigation in percutaneous coronary intervention (MPCI) vs. conventional percutaneous coronary intervention (CPCI) for the treatment of acute myocardial infarction.Methods and resultsWe compared 65 sequential patients (mean age 61 ± 15 years) undergoing primary MPCI with those of 405 patients undergoing CPCI (mean age 61 ± 13 years). The major endpoint was contrast media use. Technical success and procedural outcomes were evaluated. Clinical demographics and angiographic characteristics of the two groups were similar, except for fewer patients with previous coronary artery bypass grafting (CABG) and hypertension in the CPCI group and fewer patients with diabetes in the MPCI group. The technical success rate was high in both the MPCI and CPCI groups (95.4 vs. 98). There was significantly less contrast media usage in the MPCI compared with the CPCI group, median reduction of contrast media of 30 mL with an OR 0.41 (0.210.81). Fluoroscopy times were significantly reduced for MPCI compared with CPCI, median reduction of 7.2 min with an OR 0.42 (0.200.79).ConclusionThis comparison indicates the feasibility and non-inferiority of magnetic navigation in performing primary PCI and suggests the possibility of reductions in contrast media use and fluoroscopy time compared with CPCI. http://repub.eur.nl/res/pub/35378/ 2007-06-01T00:00:00Z The principal therapy in patients with myocardial infarction to limit infarct size is myocardial reperfusion by mechanical or pharmacological intervention. Reperfusion has been proposed to cause myocardial injury beyond that caused by the preceding ischaemia, termed "reperfusion injury" (RI). While the precise mechanism of RI is still incompletely understood, a large number of clinical studies have been performed over the past decade targeting some of the postulated mechanisms of RI. These clinical studies were based on experimental data demonstrating significant myocardial salvage. Nevertheless, clinical benefits were absent or very limited. The purpose of this review is to provide an overview of the various strategies that inhibit RI and to discuss potential mechanisms that may contribute to the discrepancy between the promising pre-clinical data and the rather disappointing results obtained from prospective clinical trials. There are numerous differences between the experimental models and clinical studies, including the fact that experimental studies typically use abrupt occlusion and reperfusion protocols in animals with previously healthy myocardium that apparently do not predict the therapeutic efficacy of novel cardioprotective agents in a clinical setting with pre-existing progressive coronary disease, intermittent coronary occlusion, and relatively late reperfusion. However, discrepancies also exist between experimental studies. Future experimental studies of reperfusion injury should use models that mimic the clinical situation more closely. Furthermore, future large clinical trials should only be performed in cases where the drug under investigation proved to reduce RI in a series of well-designed (possibly multicenter) experimental studies and in clinical trials with predefined subgroups. http://repub.eur.nl/res/pub/13703/ 2005-03-01T00:00:00Z BACKGROUND: The use of sirolimus-eluting coronary stents has been associated with a nearly complete elimination of restenosis at 6 months and with a very low 1-year incidence of major adverse cardiac events (MACE). This analysis examined whether these beneficial effects persist over the longer term. METHODS AND RESULTS: This multicenter trial randomly assigned 238 patients to revascularization of single, de novo, native coronary artery lesions with sirolimus-eluting versus conventional bare-metal stents. Survival free from target lesion revascularization (TLR), target vessel failure (TVF), and MACE up to 3 years of follow-up was compared between the 2 treatment groups. Complete data sets were available in 94.2% of patients treated with sirolimus-eluting stents and in 94.1% of patients randomized to the control group. The cumulative 1-, 2-, and 3-year event-free survival rates were 99.2%, 96.5%, and 93.7% for TLR and 95.8%, 92.3%, and 87.9% for TVF, respectively, in the sirolimus-eluting stent group, versus 75.9%, 75.9%, and 75.0% for TLR and 71.2%, 69.4%, and 67.3% for TVF in the control group (P<0.001 for both comparisons at 3 years). Rates of MACE at 3 years were 15.8% in patients randomly assigned to sirolimus-eluting stents versus 33.1% in patients assigned to bare-metal stents (P=0.002). One patient treated with a sirolimus-eluting stent died of a cardiac cause between 12 and 36 months. CONCLUSIONS: Treatment of de novo coronary stenosis with sirolimus-eluting stents was associated with a sustained clinical benefit and very low rates of TLR and of other MACE up to 3 years after device implantation. http://repub.eur.nl/res/pub/4642/ 2004-09-01T00:00:00Z BACKGROUND: The purpose of this study was to compare the safety, efficacy, and costs of complete versus "culprit" vessel revascularization in multivessel coronary artery disease treated with percutaneous coronary interventions (PCI). METHODS: Patients with multivessel disease and an identified culprit vessel were randomly assigned to complete revascularization of vessels > or =50% stenoses (n = 108) versus revascularization limited to the culprit vessel (n = 111). The primary end point, major adverse cardiac events (MACE), were defined as cardiac or noncardiac death, myocardial infarction, need for coronary artery bypass graft surgery, and repeat PCI up to 1 year. RESULTS: Despite equal MACE at 24 hours (6.3% vs 7.4%), strategy success was higher in the culprit vessel than in the complete revascularization group (93.7% vs 81.5%, P =.007). MACE rates at 1 month (14.4% vs 9.3%), 1 year (32.4% vs 26.9%), and 4.6 +/- 1.2 years (40.4% vs 34.6%) were similar in both groups. Repeat PCI was performed more often in the culprit vessel group (31.2% vs 21.2%, P =.06). A lower consumption of medical material was associated with lower procedural costs in the culprit vessel group (5784 vs 7315 Euros; P <.001). However, between 1 year and the end of follow-up, costs had equalized in both groups. CONCLUSIONS: Complete versus culprit vessel revascularization in multivessel coronary disease treated with PCI was associated with a lower strategy success rate, similar MACE rates, and initially higher costs. However, over the long term, more repeat PCIs were conducted in patients treated by culprit revascularization only, mostly because of the need to treat lesions initially left untreated. As a consequence, incremental costs had equalized within 1 year. The decision of whether to perform culprit vessel or complete revascularization can be made on an individual basis. http://repub.eur.nl/res/pub/5726/ 2004-03-01T00:00:00Z AIM: ITF-1697 is a C-reactive protein-derived tetrapeptide that, based on pre-clinical studies, is thought to reduce reperfusion injury. We performed a dose-finding study to assess safety, preliminary efficacy and clinical outcome of prolonged i.v. infusion of ITF-1697 in patients with an acute myocardial infarction (AMI) who were eligible for percutaneous coronary intervention (PCI). METHODS AND RESULTS: This was a multicentre dose-finding study that was randomised, double blind, and placebo-controlled. Four hundred and two patients were enrolled. Intravenous infusion of four dosages of ITF-1697 (0.1, 0.5, 1.0 or 2.0 microg/kg/min) or placebo was started before PCI and continued for 24 h. After interim analysis of data from 242 patients the study continued with the 0.1 and 1.0 microg/kg/min ITF-1697 regimes. Analysis did not raise any safety concerns. Post-procedure perfusion, assessed by TIMI flow, corrected TIMI frame count, blushgrade and ST-segment resolution, was similar for the placebo, 0.1 and 1.0 microg/kg/min regimes. Furthermore, the results showed no differences between the treatment regimes in enzymatic infarct size or clinical outcome up to 30 days. CONCLUSION: ITF-1697 was well tolerated. However, neither a dose-relation nor improvement of perfusion, clinical outcome or reduction of myocardial damage could be demonstrated with ITF-1697 during and after primary PCI for AMI. http://repub.eur.nl/res/pub/10290/ 2004-01-01T00:00:00Z Patients with diabetes mellitus have less favourable outcomes after percutaneous coronary intervention (PCI) than non-diabetics. We performed a subgroup analysis of the multicentre RAVEL trial to examine the impact of the sirolimus-eluting stent (SES) on outcomes in diabetic patients. The RAVEL study randomized 238 patients to treatment with either sirolimus-eluting or bare metal stents. Forty-four patients were diabetic; 19 received sirolimus-eluting stents and 25 were treated with bare metal stents. The differences in outcomes between diabetic and non-diabetic patients treated with SES (n=101) were also assessed. Follow-up angiography was performed at 6 months. Major adverse cardiac events (MACE) defined as death, myocardial infarction (MI), or target lesion revascularization (TLR) were analysed at 12-month follow-up. Six-month in-stent late lumen loss was significantly lower for the diabetic SES than the bare stent group (0.07+/-0.2 vs 0.82+/-0.5mm; P<0.001) and similar to that in non-diabetics treated with SES (-0.03+/-0.27mm). There was zero restenosis in the SES groups (diabetic and non-diabetic) compared to a 42% rate in the diabetic population assigned to bare metal stents (P=0.001). After 12 months, there was one non-Q-wave MI and one non-cardiac death in the diabetic SES group, while 12 patients in the bare metal stent group had MACE (one death, two MI, nine TLR) (P=0.01)-an event-free survival rate of 90% vs 52%, respectively (P<0.01). There were no TLRs in both SES groups compared to 36% rate in the diabetic bare metal stent group (P=0.007).Conclusion Diabetics treated with SES were associated with a virtual abolition of neointimal proliferation and low event rates at long-term follow-up. http://repub.eur.nl/res/pub/4748/ 2003-09-26T00:00:00Z Abstract OBJECTIVES: To review the currently available data from studies assessing feasibility, safety, clinical outcome and cost-effectiveness of direct stenting. BACKGROUND: With technical advances of stent designs and their delivery systems a new strategy has become increasingly popular: direct stent implantation without prior balloon dilatation. METHODS: The Medline database was searched from January 1996 to March 2001 for clinical trials investigating direct stenting using the index terms direct stenting, coronary intervention, percutaneous transluminal coronary angioplasty (PTCA), PCI, angioplasty and ischemic heart disease. Studies were chosen based on the number of patients involved and endpoints mentioned. Data not yet published but presented at recent international meetings were also included. A comparison between direct stenting and stenting with predilatation was performed using for the latter results of the randomized trials supplemented with Benestent II data. RESULTS: At least 26 studies have investigated direct stenting, showing high primary and final success rates with few complications. Direct stenting provides a way to reduce costs, shorten procedural and fluoroscopy times and lower material consumption. Immediate and long-term clinical outcomes appear to be similar to stenting with predilatation. Preliminary results of large randomized trials with angiographic follow-up indicate that restenosis rates are similar to those of conventional stenting strategies. CONCLUSIONS: Direct stenting compared with stenting with predilatation is feasible, safe, faster and more cost-effective. The evidence to date shows similar late outcomes. http://repub.eur.nl/res/pub/4737/ 2003-03-01T00:00:00Z Study objectives To compare the long-term angiographic, clinical and economic outcome of direct stenting vs stenting after balloon predilatation. Patient population and methods Four hundred patients with coronary stenoses in a single native vessel were randomized to direct stenting vs stenting after predilatation. A major adverse cardiac and cerebral event (MACCE) was defined as death, myocardial infarction, stent thrombosis, target restenosis, repeat target- and non-target vessel-related percutaneous coronary intervention, target lesion revascularization, coronary artery bypass surgery and stroke. Results Stents were successfully implanted in 98.3% of patients randomized to direct stenting vs 97.8% randomized to stenting preceded by predilatation. The primary success rate of direct stenting was 88.3%, vs 97.8% for stenting preceded by balloon dilatation . The angiographic follow-up at 6 months included 333 of the 400 patients (83%). The binary in-stent restenosis rate was 23.1% of 163 patients randomized to direct stenting vs 18.8% of 166 patients randomized to balloon predilatation . By 185±25 days, MACCE had occurred in 31 of 200 (15.5%) patients randomized to direct stenting, vs 33 of 200 (16.5%) randomized to predilatation . At 6 months, costs associated with the direct stenting strategy (Euros 3222/patient) were similar to those associated with predilatation (Euros 3428/patient, ). However, procedural costs were significantly lower. It is noteworthy that, on multivariate analysis, a baseline C-reactive protein level >10mgl−1was a predictor of restenosis (odds ratio: 2.10, ) as well as of MACCE (odds ratio: 1.94, ). Conclusions Compared to stenting preceded by balloon predilatation, direct stenting was associated with similar 6-month restenosis and MACCE rates. Procedural, but not overall 6-month costs, were reduced by direct stenting. An increased baseline CRP level was an independent predictor of adverse long-term outcome after coronary stent implantation. http://repub.eur.nl/res/pub/12815/ 1999-11-19T00:00:00Z BACKGROUND: The CAPTURE study (c 7E3 A nti P latelet T herapy in U nstable Re fractory angina) was designed to assess outcome in patients with refractory angina undergoing angioplasty, receiving either abciximab or placebo. METHODS: One thousand two hundred and sixty-five patients with refractory unstable angina, defined as recurrent myocardial ischaemia despite medical treatment including heparin and nitrates were enrolled. After angiography, patients received an infusion of abciximab or placebo over 18-24 h preceding angioplasty, continuing until 1 h after the procedure. In 1197 patients undergoing angioplasty the angiographic committee centrally reviewed the baseline as well as the procedural angiograms. Coronary flow and lesion characteristics were assessed in the baseline angiogram as well as before intervention. Angiographic outcome, reason for failure as well as complications were assessed after angioplasty. RESULTS: At 30 days follow-up, patients receiving abciximab (n=595) compared with placebo (n=602) had a 30% reduction in the composite primary end-point death, myocardial infarction or urgent (re)intervention: 10.8% vs 15.4% (P=0.017). Baseline demographics were identical in the angiogram available group compared with the total study group. At 30 days, the non-angiogram available patients showed a higher incidence of events compared to those in whom the angiogram was reviewed: 19.4 vs 13.1% (P=ns). Lesion characteristics and coronary flow were not different at baseline between the placebo and abciximab groups. A primary end-point was reached in 9.6% of both placebo and abciximab patients with type A or B(1)lesions, in 17.0% vs 12.0% with type B(2)lesions, and in 19.1% vs 11.5% with type >B(2)or C lesions. Sixty-one percent of placebo and abciximab patients had TIMI 3 flow at baseline angiography. Pre-angioplasty TIMI 3 flow was observed in 69% and 72% respectively. The thrombus was resolved between the angiograms in 22% and 43% respectively, in the placebo and abciximab groups (P=0. 033). Angiographic success of the procedure was achieved in 88% and 94% in the placebo and abciximab patients, respectively (P<0.001). Stents were implanted in the ischaemia-related artery in 56 and 60 patients, respectively. However, failure of the stent procedure was more frequent in the placebo group than in the abciximab group, nine vs no patients (P=0.003). CONCLUSION: More frequent thrombus resolution was observed and a higher angiographic success rate was achieved in patients treated with abciximab before and during angioplasty compared with placebo. Patients with complex lesions as the underlying pathology reached fewer end-points if treated with abciximab before and during angioplasty. http://repub.eur.nl/res/pub/5070/ 1995-01-01T00:00:00Z Abstract Background. The likelihood of restenosis is a major limitation of coronary angioplasty. We studied whether hirudin, a highly selective inhibitor of thrombin with irreversible effects, would revent restenosis after angioplasty. We compared two regimens of recombinant hirudin with heparin. Methods. We randomly assigned 1141 patients with unstable angina who were scheduled for angioplasty to receive one of three treatments: (1) a bolus dose of 10,000 IU of heparin followed by an intravenous infusion of heparin for 24 hours and subcutaneous placebo twice daily for three days (382 patients), (2) a bolus dose of 40 mg of hirudin followed by an intravenous infusion of hirudin for 24 hours and subcutaneous placebo twice daily for three days (381 patients), or (3) the same hirudin regimen except that 40 mg of hirudin was given subcutaneously instead of placebo twice daily for three days (378 patients). The primary end point was event-free survival at seven months. Other end points were early cardiac events (within 96 hours), bleeding and other complications of the study treatment, and angiographic measurements of coronary diameter at six months of follow-up. Results. At seven months, event-free survival was 67.3 percent in the group receiving heparin, 63.5 percent in the group receiving intravenous hirudin, and 68.0 percent in the group receiving both intravenous and subcutaneous hirudin (P = 0.61). However, the administration of hirudin was associated with a significant reduction in early cardiac events, which occurred in 11.0, 7.9, and 5.6 percent of patients in the respective groups (combined relative risk with hirudin, 0.61; 95 percent confidence interval, 0.41 to 0.90; P = 0.023). The mean minimal luminal diameters in the respective groups on follow-up angiography at six months were 1.54, 1.47, and 1.56 mm (P = 0.08). Conclusions. Although significantly fewer early cardiac events occurred with hirudin than with heparin, hirudin had no apparent benefit with longer-term follow-up. http://repub.eur.nl/res/pub/4540/ 1993-01-01T00:00:00Z BACKGROUND. Enhanced thrombin activity has been associated with acute and long-term complications following balloon angioplasty (percutaneous transluminal coronary angioplasty (PTCA). We evaluated, in a 2-to-1 randomized, double-blind trial, the effects of recombinant hirudin, CGP 39 393, relative to unfractionated sodium heparin on periprocedural events, bleeding, early angiographic outcome, and coagulation in 113 patients with stable angina undergoing PTCA. METHODS AND RESULTS. Prior to PTCA, 20 mg CGP 39 393 was administered as a bolus, followed by continuous infusion at a rate of 0.16 mg.kg-1 x h-1, or 10,000 IU sodium heparin was administered as a bolus and continued at a rate of 12 IU.kg-1 x h-1 for 24 hours. Infusion was adjusted to activated partial thromboplastin time (APTT) levels. ST segment was monitored for 24 hours, and angiograms were analyzed with quantitative technique (QCA). In 74 CGP 39 393- and 39 heparin-treated patients, 132 lesions were dilated. Myocardial infarction and/or emergency coronary bypass surgery occurred in 1 (1.4%) CGP 39 393 patient compared with 4 (10.3%) heparin patients (relative risk, 7.6; 95% confidence interval, 0.9, 65.6). At 24 hours, complete perfusion was present in 91% heparin and 100% CGP 39 393 patients. Significant ST segment displacement was found in 11% of heparin versus 4% of CGP 39 393 subjects. Bleeding occurred only at the puncture site in 4 CGP 39 393-treated patients. QCA did not reveal significant differences between the groups. APTT values were more often in the target range and more stable in CGP 39 393 patients. Levels of thrombin-antithrombin III complexes, prothrombin fragment F1+2, and fibrinopeptide A indicated that CGP 39 393 was an effective inhibitor of thrombin activity. CONCLUSIONS. CGP 39 393 can safely be administered to patients undergoing elective PTCA for stable anginal symptoms and may have a more favorable anticoagulant profile than heparin. http://repub.eur.nl/res/pub/4545/ 1993-01-01T00:00:00Z Because of the unavoidable occurrence of vessel disruption after successful coronary balloon angioplasty, the reliability of quantitative angiographic analysis in that setting has been questioned. For this reason and the suggested occurrence of delayed elastic recoil, repeat angiography at 24 hours has been advocated in clinical interventional trials. In this study, these issues are confronted by performing comprehensive quantitative analysis (Cardiovascular Angiographic Analysis System) of coronary angiograms, acquired in multiple identical projections immediately after and 24 hours after angioplasty, in 102 patients with 110 successfully dilated lesions. Vasomotion was controlled by intracoronary nitrate before angiography and all patients were fully anticoagulated (activated partial thromboplastin time 85 to 120 seconds) for > 24 hours. Paired Student's t tests applied to angiographic measurements revealed that there was no significant deterioration in minimal luminal diameter or cross-sectional area from immediately after angioplasty to 24 hours later. It can thus be inferred that there is no phenomenon of delayed elastic recoil, at least during this time period. Measurement accuracy and precision of the Cardiovascular Angiographic Analysis System from the postangioplasty angiogram are highly acceptable, at < 0.01 and +/- 0.20 mm, respectively. Therefore, it is concluded that routine repeat 24-hour angiography is not indicated after successful angioplasty. A highly significant increase (p < 0.001) in reference diameter (+0.11 +/- 0.18 mm) was responsible for the apparent increase in percent diameter stenosis (2.4 +/- 7%), a finding that demonstrates the potential for error by selective application of percent diameter stenosis measurements alone. Preferential use of absolute luminal measurements is thus strongly recommended for clinical trials with angiographic monitoring. http://repub.eur.nl/res/pub/4445/ 1992-01-01T00:00:00Z Restenosis after coronary angioplasty is the single complication that most limits this revascularization procedure in clinical practice. The process is largely unpredictable and the lesion-related factors predisposing to restenosis are poorly understood, with little consensus in published reports. In this study using detailed quantitative angiographic measurements to assess 490 lesions, the simple lesion characteristics associated with restenosis were defined and the relation to the restenosis process documented. Restenosis was defined as an absolute deterioration in the minimal lumen diameter by greater than or equal to 0.72 mm, a criterion based on the 95% confidence intervals for repeat angiographic measurements. This was chosen in an attempt to separate spurious changes due to a poor angiographic result and the variability of angiographic measurements from significant changes due to the restenosis process. The principal determinants of restenosis were found to be a large improvement in the minimal lumen diameter at the time of dilation (1.13 mm for the restenosis group compared with 0.86 mm for the no restenosis group [p less than 0.0001]) and an optimal postangioplasty result (minimal lumen diameter 2.28 mm in the restenosis group compared with 2.05 mm [p less than 0.001] in the no restenosis group, corresponding to a 25% and a 30% diameter stenosis, respectively [p less than 0.0001]). These observations reported for the first time suggest that the distinction needs to be made between a "clinical restenosis" of greater than or equal to 50% diameter stenosis and the "restenosis process" as measured by the absolute changes occurring during and after angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS) http://repub.eur.nl/res/pub/4412/ 1991-01-01T00:00:00Z BACKGROUND. Acute coronary artery occlusion after percutaneous transluminal coronary angioplasty (PTCA) continues to remain a serious complication despite significant improvement in operator performance and technological advancements. This retrospective study was performed to ascertain the frequency, predictive variables, management, and outcome of acute coronary artery occlusion. METHODS AND RESULTS. The study was based on data from 1,423 consecutive patients who underwent an elective coronary angioplasty between January 1986 and December 1988. Acute coronary artery occlusion occurred in 104 patients (7.3%). Acute occlusion developed during the dilatation procedure in 80 patients (5.6%) and within 24 hours after the procedure in 24 patients (1.7%). Four clinical and 14 angiographic variables predictive for acute coronary artery occlusion were analyzed in these 104 patients with a complicated procedure and were compared with those in 104 representative patients with successful attempts. Multivariate analysis found three independent predictive variables: unstable angina, multivessel disease, and complex lesions. The overall clinical outcome after management of acute coronary artery occlusion including immediate repeat dilatation (95 patients), use of intracoronary streptokinase (34 patients), or autoperfusion catheter (12 patients) was successful (reduction of lumen diameter to less than 50%, no death, no myocardial infarction [MI], and no emergency surgery) in 42 patients (40%), was a failure without major complication in four patients (4%), and was a failure with major complication (death, MI, and emergency surgery) in 58 patients (56%). The overall mortality rate was 6% (six patients), the overall MI rate was 36% (37 patients), and emergency bypass surgery was required in 30% of patients (31 patients). At 6 months' follow-up of 42 patients with successful management, recurrent angina pectoris due to restenosis occurred in 10 patients (24%), and a late MI occurred in one patient (3%). At 6 months' follow-up of 56 survivors with unsuccessful management (development of MI or need for emergency bypass surgery), recurrent angina occurred in nine patients (16%), and cardiac death in two patients (4%). However, the majority of patients in both groups were either symptom free or had mild angina pectoris. CONCLUSION. Acute coronary artery occlusion during PTCA is often unpredictable, but its frequency is higher in patients with unstable angina, multivessel disease, and complex lesions. Despite immediate redilatation, use of intracoronary streptokinase, and emergency bypass surgery, PTCA is associated with a high mortality and morbidity. http://repub.eur.nl/res/pub/4413/ 1991-01-01T00:00:00Z The incidence of major complications after percutaneous coronary angioplasty (PTCA) of a totally occluded artery was assessed retrospectively. A total of 1649 PTCA procedures were analyzed. After exclusion of procedures for acute myocardial infarction or total occlusion that resulted from restenosis, 90 patients were selected. Forty-four patients (49%) had stable angina and 46 (51%) had unstable angina. The estimated duration of occlusion was 87 +/- 78 days in patients with stable angina, as compared with 10 +/- 8 days in patients with unstable angina (p less than 0.001). Abrupt vessel closure during PTCA occurred only in patients with unstable angina (0% versus 17%, p less than 0.05). The major complication rate was 2.5% in the stable angina group, and 20% in unstable angina group (p less than 0.01). This rate was also significantly higher than the complication rate of 8% observed in 442 procedures that were performed during the same period in patients with the unstable angina and nonocclusive stenosis (p less than 0.01). Patients with unstable angina who undergo PTCA of a totally occluded artery represent a subset of high risk for major complications. http://repub.eur.nl/res/pub/4436/ 1991-01-01T00:00:00Z To determine functional and anatomic changes in the first 24 hours after coronary angioplasty, we studied at random 15 patients (9 men, mean age 60 years) who underwent coronary angioplasty of 16 coronary arteries. Quantitative coronary angiography and coronary flow reserve measurements from digitized coronary angiograms were performed before, immediately after, and 24 hours after coronary angioplasty. Calculated were the minimal luminal diameter, obstruction area, and percentage diameter stenosis from two preferably orthogonal projections. Prior myocardial infarction in the myocardial region of interest was present in four patients. Seven patients had multivessel disease. Collateral vessels supplying the compromised flow region were observed in three patients. Six patients had refractory unstable angina pectoris. After coronary angioplasty, angiographically visible dissection was noted in six patients, whereas side branch occlusion was observed in one. Minimal luminal diameter before, immediately after, and 24 hours after was 0.93 +/- 0.18 mm, 1.53 +/- 28 mm, and 1.53 +/- 0.21 mm, respectively; obstruction area was 0.70 +/- 0.26 mm2, 1.92 +/- 0.69 mm2, and 1.87 +/- 0.51 mm2, respectively; diameter stenosis was 60.4 +/- 8.0%, 36.8 +/- 11.4%, and 37.6 +/- 5.3%, respectively. The coronary flow reserve (lower limit of normal with this technique 3.4) was essentially the same before and immediately after coronary angioplasty (1.26 +/- 0.59 vs 1.30 +/- 0.42, p = NS) with a slight improvement to 1.78 +/- 0.90 (p less than 0.05) 1 day later. Coronary artery dimensions correlated poorly with coronary blood flow reserve before and after angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS) http://repub.eur.nl/res/pub/4374/ 1990-01-01T00:00:00Z http://repub.eur.nl/res/pub/4383/ 1990-01-01T00:00:00Z Intravenous dipyridamole thallium testing is a useful alternative procedure for assessing coronary artery disease (CAD) in patients who are unable to perform maximal exercise tests. Ischaemic ST segment depression and angina pectoris are frequently observed during the test, in particular when exercise is added to dipyridamole infusion. To establish the clinical significance and additional diagnostic value of these markers of ischaemia during dipyridamole low-level exercise testing (DXT) 57 patients with CAD (group A), 21 patients with normal or near-normal coronary arteries at coronary arteriography (group B), and 20 healthy subjects with low likelihood of CAD (group C) were studied. During DXT ischaemic ST segment depression was observed in 28 patients (47%) of group A and in two patients (10%) of group B. Angina pectoris was experienced by 35 patients (61%) of group A and by five patients (24%) of group B. The positive predictive value of both ST depression and angina pectoris was high (88 and 93%, respectively), but the negative predictive values were low (42 and 40%, respectively). Combining ST segment analysis with the findings of thallium imaging significantly increased the diagnostic accuracy of the test. ST segment depression, angina pectoris, and thallium abnormalities were highly specific findings if the study population consisted of asymptomatic subjects with a low likelihood of CAD (group C). Sensitivity for the detection of the presence of CAD increased with the extent of CAD for all parameters studied. Thus, ST depression and angina pectoris, alone or in combination, during DXT have little diagnostic significance, although sensitivity is increased in patients with triple-vessel CAD.(ABSTRACT TRUNCATED AT 250 WORDS) http://repub.eur.nl/res/pub/4385/ 1990-01-01T00:00:00Z Exercise electrocardiographic (ECG) testing during follow-up after coronary angioplasty is widely applied to evaluate the efficacy of angioplasty, even in asymptomatic patients. One hundred forty-one asymptomatic patients without previous myocardial infarction underwent quantitative exercise ECG testing and quantitative coronary angiography 1 to 6 months after successful angioplasty in single vessel coronary artery disease to 1) determine the value of exercise ECG testing to detect "silent" restenosis, and 2) assess the long-term prognostic value of exercise ECG testing and coronary angiography. The prevalence of restenosis (defined as greater than or equal to 50% luminal narrowing at the dilation site) was 12% in this selected study group. Of 26 patients with an abnormal exercise ECG (ST segment depression greater than or equal to 0.1 mV), only 4 (15%) showed recurrence of stenosis. Sensitivity and specificity for detection of restenosis were 24% and 82%, respectively. One hundred thirty-four patients (95%) were followed up 1 to 64 months (mean 35) after exercise ECG testing and coronary angiography. Thirty-two patients (24%) experienced a cardiac event: in 25 patients (78%) the initial event was recurrent angina pectoris (New York Heart Association class III or IV) and in 7 patients (22%) it was myocardial infarction, although cardiac death did not occur. The mean interval between exercise ECG testing and the initial cardiac events was 14 months (range 1 to 55), whereas 47% of the initial events took place less than or equal to 6 months after exercise ECG testing.(ABSTRACT TRUNCATED AT 250 WORDS) http://repub.eur.nl/res/pub/4386/ 1990-01-01T00:00:00Z http://repub.eur.nl/res/pub/4393/ 1990-01-01T00:00:00Z Little is known about the elastic behavior of the coronary vessel wall directly after percutaneous transluminal coronary angioplasty (PTCA). Minimal luminal cross-sectional areas of 151 successfully dilated lesions were studied in 136 patients during balloon inflation and directly after withdrawal of the balloon. The circumvent geometric assumptions about the shape of the stenosis after PTCA, a videodensitometric analysis technique was used for the assessment of vascular cross-sectional areas. Elastic recoil was defined as the difference between balloon cross-sectional area of the largest balloon used at the highest pressure and minimal luminal cross-sectional area after PTCA. Mean balloon cross-sectional area was 5.2 +/- 1.6 mm2 with a mean minimal cross-sectional area of 2.8 +/- 1.4 mm2 immediately after inflation. Oversizing of the balloon (balloon artery ratio greater than 1) led to more recoil (0.8 +/- 0.3 vs 0.6 +/- 0.3 mm, p less than 0.001), suggestive of an elastic phenomenon. A difference in recoil of the 3 main coronary branches was observed: left anterior descending artery 2.7 +/- 1.3 mm2, circumflex artery 2.3 +/- 1.2 mm2 and right coronary artery 1.9 +/- 1.5 mm2 (p less than 0.025). The difference was still statistically significant if adjusted for reference area. Thus, nearly 50% of the theoretically achievable cross-sectional area (i.e., balloon cross-sectional area) is lost shortly after balloon deflation. http://repub.eur.nl/res/pub/4397/ 1990-01-01T00:00:00Z -- http://repub.eur.nl/res/pub/4331/ 1989-01-01T00:00:00Z Intracoronary blood flow velocity measurements with a Doppler balloon catheter and the radiographic assessment of myocardial perfusion with contrast media, before and after the intracoronary administration of papaverine, have previously been used to investigate regional coronary flow reserve. In the present study we applied both techniques in 21 patients to measure coronary flow reserve in the setting of coronary angioplasty. Pre-angioplasty (N = 14) and post-angioplasty (N = 19) measurements of coronary flow reserve were obtained by digital subtraction cineangiography in the myocardial region supplied by the dilated coronary artery, and with the Doppler probe in the proximal part of the dilated vessel. The reactive hyperaemia following the final balloon inflation was recorded with the Doppler balloon catheter still positioned across the stenotic lesion. Coronary stenosis geometry was quantified with the Cardiovascular Angiography Analysis System. When the epicardial stenosis was the only factor causing a reduction in coronary flow reserve, flow reserve measured with both digital subtraction cineangiography and with the Doppler probe correlated well with the cross-sectional area at the site of obstruction, r = 0.88, SEE = 0.36 and r = 0.77, SEE = 0.45 respectively. In contrast, when other factors decreasing coronary flow reserve were present (intimal dissection, left ventricular hypertrophy, previous myocardial infarction, collaterals) measurements obtained with both techniques correlated poorly with cross-sectional area (r = 0.55, SEE = 0.57, and r = 0.59, SEE = 0.50). Flow reserve measurements obtained with digital subtraction cineangiography correlated well with the measurements obtained with the Doppler probe (r = 0.85, SEE = 0.38, and r = 0.87, SEE = 0.34), although the two approaches have methodologically nothing in common and their respective regions of interest (myocardium for the radiographic technique and intracoronary lumen for the Doppler technique) are basically different. Furthermore, the reactive hyperaemia following the final balloon inflation was related to the flow reserve measured with both the angiographic technique (r = 0.85, SEE = 0.34) and the Doppler technique (r = 0.83, SEE = 0.32) using pharmacologically induced coronary vasodilation with intracoronary papaverine. This suggests that the same quantity of coronary flow reserve that can be recruited pharmacologically can be recruited by ischaemia following a transluminal occlusion.