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C A Ascoop

Publications and source records attributed to C A Ascoop.

At least 19 recordsLinked to original sources
PubMed1999

Worse clinical outcome but similar graft patency in women versus men one year after coronary artery bypass graft surgery owing to an excess of exposed risk factors in women. CABADAS. Research Group of the Interuniversity Cardiology Institute of The Netherlands. Coronary Artery Bypass graft occlusion by Aspirin, Dipyridamole and Acenocoumarol/phenoprocoumon Study.

OBJECTIVES: This retrospective study sought to assess differences in graft patency and clinical outcome between women and men after coronary artery bypass graft surgery (CABG). BACKGROUND: A less favorable clinical outcome has been reported in women as compared with men. Its relation to graft patency has not been studied. METHODS: We analyzed one-year follow-up data of 912 patients (120 women) who entered a randomized clinical drug trial. All patients received vein grafts; in 494 patients (56 women) internal mammary artery (IMA) grafts were also used. Graft patency was assessed by coronary angiography at one year. Primary clinical end points were myocardial infarction, revascularization procedures and death; secondary clinical end points included recurrent angina, heart failure and arrhythmias. RESULTS: Occlusion rates of vein grafts were 16.7% in women and 12.4% in men (odds ratio [OR] 1.62, 95% confidence interval [CI] 0.88 to 3.00, p = 0.12); occlusion rates of IMA grafts were 3.4% and 5.7% in women and men, respectively (OR 0.56, 95% CI 0.08 to 3.96, p = 0.56). Primary clinical end points were observed in 16.7% of women and 9.2% of men (OR 1.97, 95% CI 1.10 to 3.34, p = 0.022), and any clinical end point in 41.7% of women and 25.8% of men (OR 2.06, 95% CI 1.39 to 3.04, p = 0.0004). Myocardial infarction (15% vs. 7.6%, OR 2.15, 95% CI 1.24 to 3.75, p = 0.013) and recurrent angina (26.7% vs. 15.4%, OR 2.00, 95% CI 1.28 to 3.11, p = 0.004) occurred most frequently. Multivariate regression analysis did not identify gender as an independent risk factor for graft occlusion or the clinical end points. Graft occlusion was an independent predictor of the composite primary clinical end point (OR 2.75, 95% CI 1.59 to 4.75, p = 0.0003) and each of the secondary clinical end points. The observed differences were due to an imbalance of risk factors at baseline and to surgical and graft characteristics. CONCLUSIONS: One-year occlusion rates of vein and IMA grafts were comparable in women and men. Clinical outcome was related to graft patency and was less favorable in women owing to their uneven distribution of risk factors among both groups.

Aged↗
PubMed1997

Exercise capacity after His bundle ablation and rate response ventricular pacing for drug refractory chronic atrial fibrillation.

OBJECTIVE: To evaluate exercise capacity of patients with chronic atrial fibrillation in whom His bundle ablation followed by ventricular rate response pacing (VVIR) was carried out because of drug refractoriness. DESIGN: Prospective study. PATIENTS: 25 consecutive patients, all with chronic symptomatic drug refractory atrial fibrillation, underwent His bundle ablation. Before this intervention all patients were on antiarrhythmic drugs to attain acceptable heart rate control and to relief symptoms. MAIN OUTCOME MEASURES: Exercise capacity, including measurements of VO2, was examined before and after a mean interval of seven months following His bundle ablation. RESULTS: Exercise capacity after His bundle ablation increased from a mean of 109 (SD 49) W to 118 (46) W (P < 0.002), but VO2 at peak exercise did not change significantly. Maximum exercise capacity was achieved with a significantly lower maximum driven heart rate than the spontaneous heart rate before ablation. CONCLUSIONS: Exercise capacity of patients who underwent His bundle ablation followed by VVIR pacing remained unchanged or improved during a mean follow up of seven months. Larger patient populations with longer follow up are necessary to examine determinants of improved exercise capacity.

Atrial Fibrillation↗
PubMed1997

SPECT versus planar 99mTc-sestamibi myocardial scintigraphy: comparison of accuracy and impact on patient management in chronic ischemic heart disease.

A head-to-head comparison between 99mTc-sestamibi SPECT and planar myocardial imaging using dipyridamole low-level exercise stress was performed for the assessment of coronary artery disease (CAD) and for the impact on patient management in 78 patients (pts) who underwent coronary arteriography. Overall sensitivity and specificity for detection of CAD were 82% and 82% for SPECT, and 78% and 73% for planar imaging, respectively (both NS). Compared to planar imaging the sensitivity of SPECT imaging was significantly higher for detecting left anterior descending (p = 0.02) and left circumflex (p = 0.03) coronary artery disease. In predicting distally located stenoses, SPECT was significantly superior to planar imaging for the left circumflex artery (p = 0.025). Concordance analysis of perfusion status showed agreement in 308 of 390 (79%) of coronary flow regions both with respect to the presence or absence of perfusion and to the reversibility or irreversibility of defects (kappa = 0.60, SE 0.04). Stress-induced perfusion defects were significantly more detected by SPECT than by planar imaging (p < 0.001). Based on SPECT findings 31 pts were proposed for revascularization compared to 30 pts based on planar imaging (NS). Overall there was agreement in 65 (83%) pts regarding treatment strategy. We conclude that in a head-to-head comparison SPECT provided improved diagnostic value compared with planar imaging. However, with respect to patient treatment, the superiority of SPECT was not always translated into improved patient management.

Adult↗
PubMed1996

Comparison of technetium-99m sestamibi left ventricular wall motion and perfusion studies with thallium-201 perfusion imaging: in search of the combination of variables with the highest accuracy in predicting coronary artery disease.

Measurements of myocardial perfusion and ventricular function are expected to provide additional information in the detection of coronary artery disease (CAD). The purpose of this study was threefold: (1) to determine to what extent technetium-99m sestamibi wall motion yields different information compared with 99mTc-sestamibi and thallium-201 perfusion; (2) to test which information unique to either study is of value in diagnosing CAD; and (3) to assess the combination of variables with the highest diagnostic accuracy. Perfusion and wall motion scores (at rest and during exercise) obtained from visual and quantitative planar 201Tl and 99mTc-sestamibi scintigraphy of 60 patients with suspected CAD were compared with the angiographic results by means of a polytomous logistic regression model and the diagnostic values were compared with one another. All univariate variables were significantly related to the probability of CAD and its extent. Comparative studies revealed a large degree of correlation between 201Tl stress and redistribution variables. The rest 99mTc-sestamibi and wall motion studies contained partially different information. Stepwise logistic regression analysis showed the strongest diagnostic power for the combination of 201Tl visual analysis of the stress images with quantitative redistribution images (sensitivity 93%, specificity 71%). The diagnostic power was similar for all combinations of visual and quantitative analyses of the exercise and redistribution images. The strongest diagnostic power of the 99mTc-sestamibi variables was the score of the diastolic stress image (sensitivity 91%, specificity 79%). Comparable sensitivity and specificity estimates were found when both optimal models were compared. Wall motion studies did not have additional diagnostic power. Although 99mTc-sestamibi wall motion studies, both at rest and during exercise, provide information in addition to the 99mTc-sestamibi or 201Tl myocardial perfusion variables, the information does not enhance the diagnostic power with regard to the prediction of CAD.

Coronary Angiography↗
PubMed1996

Comparison of adenosine and high-dose dipyridamole both combined with low-level exercise stress for 99Tcm-MIBI SPET myocardial perfusion imaging.

Intravenously administered adenosine and high-dose dipyridamole, both combined with low-level exercise stress, were compared in a head-to-head fashion using 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) single photo emission tomography (SPET) myocardial perfusion imaging. Thirty-nine consecutive patients who had undergone coronary arteriography underwent 99Tcm-MIBI (740 Mbq) SPET after dipyridamole (0.84 mg kg-1) and after adenosine (0.84 mg kg-1), both combined with low-level exercise (30 W load), and under resting conditions. Our results demonstrate that adenosine and dipyridamole combined with exercise have comparable haemodynamic effects, with a low incidence of side-effects. The time of recovery from the stress protocol was not significantly different: adenosine, 5.7 +/- 3.9 min; dipyridamole, 6.6 +/- 4.9 min. However, aminophylline was significantly (P < 0.05) more often administered to reverse side-effects using the dipyridamole protocol (36% of patients) compared with the adenosine protocol (8% of patients). The results of 99Tcm-MIBI SPET imaging were highly concordant and demonstrated a high diagnostic accuracy for identifying coronary artery disease (CAD). The sensitivity was 90% (95% confidence intervals 79-100%) with adenosine SPET and 93% (95% confidence intervals 84-100%) with dipyridamole SPET for identifying patients with CAD (i.e. luminal stenosis > 50%); their specificities were both 100% (95% confidence intervals 66-100%). The sensitivity of identifying angiographically diseased vessels was 81% (95% confidence intervals 70-92%) using adenosine SPET and 85% (95% confidence intervals 75-95%) using dipyridamole; the specificity for both stress modalities was 94% (95% confidence intervals 89-100%). The combination of exercise with adenosine and high-dose dipyridamole appears to be a feasible and safe method to alleviate some of the undesirable A1-receptor-mediated side-effects of adenosine. The choice of the pharmacological stress will depend on local expertise and availability.

Adenosine↗
PubMed1996

Aprotinin in aortocoronary bypass surgery: increased risk of vein-graft occlusion and myocardial infarction? Supportive evidence from a retrospective study.

To assess the thrombotic risk of aprotinin in aortocoronary bypass surgery, we retrospectively analyzed the results of a trial, originally designed to compare the effects of one-year treatment with various antithrombotic drugs in the prevention of vein-graft occlusion. Graft patency at one year was assessed by angiography. Myocardial infarction, thromboembolism, major bleeding, and death were clinical endpoints. Of 948 randomized patients, 42 received aprotinin, all enrolled by one of the participating centres. Occlusion rates of distal anastomoses were 20.5% in the aprotinin group and 12.7% in the non-aprotinin group (p = 0.091). The proportions of patients with occluded grafts were 44.1% versus 26.3% (p = 0.029). Perioperative myocardial infarction occurred in 14.3% and 7.0%, respectively (p = 0.12). Mean postoperative blood loss was 451 ml in the aprotinin group compared with 1039 ml in the non-aprotinin group (p < 0.0001). Mean transfusion requirements were 1.1 U versus 2.1 U of red blood cells (p = 0.004). Aprotinin decreases blood loss and transfusion requirement. Our data suggest that this benefit may be associated with a reduction of graft patency and an increased risk of myocardial infarction.

Aprotinin↗
PubMed1994

Quantitative analysis of planar technetium-99m Sestamibi myocardial perfusion images. Clinical application of a modified method for the subtracton of tissue crosstalk.

Application of the Thallium-201 quantitative analysis method to Tc-99m Sestamibi planar myocardial perfusion images results in oversubtraction of tissue crosstalk, defined as 'activity within the myocardial image, which originated outside the heart'. A modified algorithm, specific for Tc-99m Sestamibi, was applied in 60 patients and the results of quantitative analysis to estimate the risk of coronary artery disease were compared with coronary angiographic findings and with visual analysis. New crosstalk planes were generated based on the results in 20 male healthy volunteers. The results in our study group indicate a higher diagnostic accuracy when circumferential profiles are generated on the basis of maximal counts compared to mean counts. Quantitative analysis was able to predict the presence or absence of CAD as accurately as visual analysis. Odds ratios were 1.07 and 1.32 respectively (P < 0.001) for both quantitative maximal uptake and visual uptake analysis. Sensitivity of visual analysis alone was 89%, increasing to 96% with combined visual/quantitative analysis. Specificity of visual analysis decreased from 79% to 64% with combined analysis. Although only minor differences are seen, the maximal count uptake profiles were found to have additional diagnostic value compared to visual analysis alone.

Adult↗
PubMed1994

99Tcm-sestamibi SPECT with combined dipyridamole and exercise stress in coronary artery disease.

In order to evaluate the clinical value of 99Tcm-methoxyisobutylisonitrile (sestamibi) single photon emission computed tomography (SPECT) after dipyridamole infusion in combination with low level bicycle exercise for the assessment of the presence, localization and extent of coronary artery disease (CAD), myocardial perfusion imaging was performed in 76 patients. Low level bicycle exercise was used to supplement the standard dipyridamole infusion protocol because of the lower incidence of non-cardiac side effects. The results were compared to arteriographic findings obtained within 3 months of the SPECT studies. The overall sensitivity of detection of coronary artery disease (i.e. a luminal stenosis > 50%) was 81%, specificity 80%, positive predictive value 96%, negative predictive value 40% and accuracy 82%. The diagnostic values for the detection of significant stenoses in the three major coronary arteries were: left anterior descending artery sensitivity 72%, specificity 87% and accuracy 76%; right coronary artery sensitivity 75%, specificity 90% and accuracy 80%; left circumflex coronary artery sensitivity 57%, specificity 85% and accuracy 71%. Scintigraphic evidence of multivessel disease was found in 31 (65%) patients with two- or three-vessel involvement assessed by arteriography. False negative test results were mainly found in patients with relatively mild CAD (one-vessel disease, branch and distal disease). 99Tcm-sestamibi SPECT after dipyridamole infusion in combination with low level bicycle exercise is shown to be a valuable diagnostic tool for the evaluation of CAD.

Adult↗
PubMed1994

Head-to-head comparison between technetium-99m-sestamibi and thallium-201 tomographic imaging for the detection of coronary artery disease using combined dipyridamole-exercise stress.

AIM: The purpose of this study was a head-to-head comparison of tomographic imaging (SPECT) with technetium-99m (Tc-99m)-sestamibi and thallium-201 (Tl-201) using dipyridamole-low-level bicycle exercise stress for the assessment of coronary artery disease. METHODS: We studied 38 consecutive patients referred for the evaluation of chest pain who had undergone coronary angiography. The patients were randomly allocated to Tc-99m-sestamibi SPECT followed by Tl-201 SPECT or vice versa. The accuracy of both tracers in detecting significant coronary artery disease (> 50% luminal stenosis) was 87% (95% confidence interval 72-96%). Only two patients were classified differently by the two methods. RESULTS: On a segmental basis, good agreement was found between Tc-99m-sestamibi and Tl-201 for both the localization and the nature of perfusion defects (reversible or persistent) identified (Cohen's kappa = 0.67). CONCLUSION: No clinically relevant differences in diagnostic accuracy were demonstrated between Tc-99m-sestamibi and Tl-201 SPECT using combined dipyridamole-exercise stress for the evaluation of coronary artery disease.

Aged↗
PubMed1993

Prevention of one-year vein-graft occlusion after aortocoronary-bypass surgery: a comparison of low-dose aspirin, low-dose aspirin plus dipyridamole, and oral anticoagulants. The CABADAS Research Group of the Interuniversity Cardiology Institute of The Netherlands.

Aspirin, alone or in combination with dipyridamole, is known to prevent occlusion of aortocoronary vein grafts. The benefit of dipyridamole in addition to aspirin remains controversial, and the efficacy and safety of oral anticoagulants for prevention of vein-graft occlusion have not been established. We assessed one-year angiographic vein-graft patency after aortocoronary-bypass surgery in 948 patients assigned to receive aspirin, aspirin plus dipyridamole, or oral anticoagulants in a prospective, randomised trial. The design was double-blind and placebo-controlled for the aspirin groups, but open for oral anticoagulant treatment. Dipyridamole (5 mg/kg per 24 h intravenously for 28 h, followed by 200 mg twice daily) and oral anticoagulants (desired prothrombin time range 2.8-4.8 international normalised ratio) were started before surgery, and aspirin (50 mg per day) was started after surgery. Clinical outcome was assessed by the incidence of myocardial infarction, thrombosis, major bleeding, or death. Occlusion rate of distal anastomoses was 11% in the aspirin plus dipyridamole group versus 15% in the aspirin group (relative risk 0.76, 95% CI 0.54-1.05) and 13% in the oral anticoagulants group. Clinical events occurred in 20.3% of patients receiving aspirin plus dipyridamole compared with 13.9% of the aspirin group (relative risk 1.46, 95% CI 1.02-2.08) and 16.9% of the oral anticoagulants group. Our data provide no convincing evidence that addition of dipyridamole to 50 mg aspirin per day improves aortocoronary vein-graft patency. Moreover, there is evidence that the combination increases the overall clinical-event rate. Compared with aspirin, oral anticoagulants provided no benefit.

Acenocoumarol↗
PubMed1993

Exercise 201Tl scintigraphy: evaluation of the additional diagnostic value.

The additional diagnostic yield of exercise 201Tl scintigraphy using both visual and quantitative analysis was determined in 221 patients with known or suspected coronary artery disease (CAD). The coronary arteriogram was adopted as the gold standard. After pretest clinical and exercise electrocardiographic data were taken into consideration, scintigraphy added diagnostic accuracy both in the diagnosis of CAD and of multivessel disease. The diagnostic yield of the scintigraphy in terms of sensitivity and specificity was, however, not significant. In 79% (121/153) of the patients, the diagnosis of the presence, or exclusion, of CAD was highly probable (P > 0.80 or P < 0.20) when considering clinical and exercise data. The diagnosis was, however, not significantly improved by the scintigraphic result. Twenty-seven per cent (20/73) returned a negative scintigraphic results with a high (P > 0.80) prescintigraphic probability for CAD and a positive arteriogram. It was concluded that 201Tl scintigraphy has additional diagnostic value after clinical and exercise parameters were taken into consideration in the diagnosis of coronary artery and multiple vessel disease. It is not recommended to refer patients with either a low or high probability of CAD for screening and diagnosis as in a high proportion of patients the diagnosis of CAD could have been made using clinical or exercise data alone.

Coronary Disease↗
PubMed1992

Initial and long-term results of percutaneous transluminal coronary angioplasty in patients 75 years of age and older.

In 212 patients aged 75 years and older the immediate and long-term results of percutaneous transluminal coronary angioplasty (PTCA) were assessed. For 293 stenoses the primary angiographic success rate was 96% and the overall clinical success rate was 90.6%. Angioplasty caused a myocardial infraction in 7 patients (3.3%), 2 patients (0.9%) needed emergency aorto coronary bypass surgery, and 4 patients (1.9%) died following the procedure. Actuarial 7 year survival was calculated at 69.3% with a standard deviation (SD) of 8%. Actuarial cardiac survival at 7 years was 92.1% (SD 3%), whereas non-cardiac survival at 7 years was 75.3% (SD 9%). Actuarially, at 7 years 98.5% (SD 1%) were estimated to remain free from myocardial infarction in the angioplasty-related area, 95.7% (SD 2%) to remain free from any myocardial infarction, 93.9% (SD 2%) to remain free from re-PTCA because of a recurrence, 84.7% (SD 5%) to remain free from any re-PTCA, and 97.1% (SD 2%) to remain free from (re)-operation. Fifty-two point three percent (SD 8%) were estimated to remain free from any cardiac event. If recurrence of angina is taken into account, only 25.8% (SD 13%) remain asymptomatic during 7 years follow-up. After successful angioplasty in patients aged 75 and older the chance of remaining free from any event or angina at 7 years actuarial follow-up gets as low as 15.7% (SD 9%). We conclude that in selected elderly patients angioplasty can be performed with a high success rate, although the periprocedural mortality and morbidity appear to be higher than in the younger age group. During long-term follow-up, most of the patients remain free of cardiac events and survival appears to be largely dependent on noncardiac factors. However, long-term relief from angina is probably less than in younger patients.

Actuarial Analysis↗
PubMed1992

Combined assessment of technetium-99m SESTAMIBI planar myocardial perfusion images at rest and during exercise with rest/exercise left ventricular wall motion studies evaluated from gated myocardial perfusion studies.

The favorable physical characteristics of technetium-99m-labeled 2-methoxy-2-methylisopropyl-1-isonitril (Tc-SESTAMIBI) enable the combined evaluation of both myocardial perfusion and left ventricular wall motion. To assess the potential of rest and exercise regional myocardial function as an adjunct to planar myocardial perfusion imaging, 60 patients with coronary artery disease and documented arteriographic findings were studied with both protocols during a single study. Exact segmental concordance between myocardial perfusion and wall motion studies was 77% (701/900 segments). Overall sensitivity and specificity to detect hemodynamically significant coronary artery disease with Tc-SESTAMIBI myocardial perfusion imaging were 89% and 79%, respectively, with resting wall motion studies 83% and 71%, respectively, and with rest/exercise wall motion studies, 85% and 71%, respectively. If the results of both perfusion and rest/exercise studies were combined, sensitivity increased to 96% and specificity decreased to 64%. The differences with perfusion studies alone were not statistically significant. Thus despite a good correlation between regional left ventricular function and perfusion, no statistically significant incremental diagnostic value was found when the results of both perfusion and wall motion studies were combined.

Adult↗
PubMed1992

Determinants for early mortality in patients awaiting coronary artery bypass graft surgery: a case-control study.

A total of 1124 consecutive patients who were selected for coronary artery bypass graft surgery were studied. Of patients awaiting surgery (mean waiting time 98 days) 25 patients (2.2%) died before operation (mean waiting time 63 days). To assess patient characteristics predictive for early mortality before surgery, 25 deceased patients were analysed and compared to 50 controls matched for age, gender, type of surgery and waiting-list priority. Univariate analysis showed that the deceased patients had a higher rate of severe angina pectoris class III-IV (odds ratio (OR) 2.9), unstable angina prior to angiography (OR 4.8), cardiac enlargement on chest X-ray (OR 13.5), positive exercise testing of short duration (less than or equal to 6 min) (OR 6.0), coumarin treatment (OR 4.2), smoking (OR 3.0), severe left main or three-vessel disease (OR 4.1), abnormal end-diastolic volume (OR 3.1) and an abnormal left ventricular wall motion score (OR 3.0). Using multivariate analysis, cardiac enlargement (OR 14.4), positive exercise testing of short duration (OR 13.3), smoking (OR 8.7), coumarin treatment (OR 7.1), unstable angina (OR 6.5) and/or left main or three-vessel disease (OR 5.4) were independent predictors for death while awaiting coronary revascularisation. Thus, patients with the above mentioned independent characteristics have an increased short-term mortality while awaiting coronary bypass graft surgery. These indicators may contribute important information for determination of priority in high risk patients awaiting coronary artery bypass graft surgery.

Adult↗
PubMed1992

Mediastinal lymph node enlargement as a result of mitral valve stenosis.

Two patients are described with severe MVS, pulmonary venous hypertension and enlarged mediastinal, pulmonary and hilar lymph nodes. These enlargements were diagnosed on a preoperative chest CT. After MV replacement these enlarged lymph nodes nearly all resolved. The lymphadenopathy should be considered to be secondary to MVS with pulmonary venous hypertension.

Female↗
PubMed1992

Evaluation of the incremental diagnostic value and impact on patient treatment of thallium scintigraphy.

The incremental diagnostic yield of exercise 201Tl scintigraphy with visual and quantitative analysis was determined in 191 patients with known or suspected coronary artery disease (CAD). The coronary arteriogram was used as the gold standard. After pre-test clinical and exercise electrocardiographic data were taken into consideration, scintigraphy was found to have additional diagnostic value both in the diagnosis of CAD and of multivessel disease, with quantitative analysis being superior to visual analysis. The impact of 201Tl scintigraphy on the patient's treatment--conservative treatment versus revascularization--was also evaluated. The impact was relatively low, as the decision for revascularization was based primarily on the angiographic result and the severity of the anginal pain. This result reflects only the decision making process used in our clinic and permits no conclusion to be made concerning the possible value of 201Tl scintigraphy in this type of medical decision making process.

Coronary Angiography↗
PubMed1991

Predictability and prognosis of PTCA-induced coronary artery aneurysms.

The natural history of coronary aneurysms, defined as local dilatations exceeding the diameter of the normal adjacent vessel segments by at least 1.5 times, is not significantly different from the natural history of nonaneurysmal coronary disease. However, little is known about the prognosis of percutaneous transluminal coronary angioplasty (PCTA)-induced coronary aneurysms. Therefore, we investigated the occurrence and the medium long-term prognosis of such aneurysms in 728 patients who, after successful PTCA, underwent repeat coronary angiography at mean 4.5 months post-PTCA. A coronary aneurysm at the site of PTCA ws noted in 3.9% of patients (n = 28). Of the potentially predictive factors analyzed, only a coronary dissection at the time of PTCA had statistically significant influence. The long-term prognosis of PTCA-induced coronary aneurysms was excellent. One patient underwent (unrelated) cardiac surgery, all other 27 patients remained eventfree. We conclude that the same benign nature of coronary aneurysmal disease holds true for those aneurysms that develop after PTCA.

Angioplasty, Balloon, Coronary↗