Abciximab and atherosclerotic heart disease: use in percutaneous coronary intervention, acute coronary syndromes and acute myocardial infarction.

Abciximab irreversibly binds to the glycoprotein IIb/IIIa receptor on both activated and unactivated platelets inhibiting platelet aggregation. It has been studied in a variety of clinical settings including percutaneous coronary intervention (PCI), ST-elevation myocardial infarction, and non ST-elevation acute coronary syndromes. Abciximab has been demonstrated to reduce acute ischaemic events in the setting of percutaneous intervention with both percutaneous transluminal coronary angioplasy and stenting. It has been shown to be particularly effective when used in patients with acute myocardial infarction undergoing primary PCI. The data for its effective use in the medical phase of therapy for patients with acute coronary syndromes, however, is not as consistent. In this article we review the major trials evaluating the use of abciximab in these clinical scenarios compared with placebo and alternative glycoprotein IIb/IIIa inhibitors.

Aspirin use and all-cause mortality among patients being evaluated for known or suspected coronary artery disease: A propensity analysis.

CONTEXT: Although aspirin has been shown to reduce cardiovascular morbidity and short-term mortality following acute myocardial infarction, the association between its use and long-term all-cause mortality has not been well defined. OBJECTIVES: To determine whether aspirin is associated with a mortality benefit in stable patients with known or suspected coronary disease and to identify patient characteristics that predict the maximum absolute mortality benefit from aspirin. DESIGN AND SETTING: Prospective, nonrandomized, observational cohort study conducted between 1990 and 1998 at an academic medical institution, with a median follow-up of 3.1 years. PATIENTS: Of 6174 consecutive adults undergoing stress echocardiography for evaluation of known or suspected coronary disease, 2310 (37%) were taking aspirin. Patients with significant valvular disease or documented contraindication to aspirin use, including peptic ulcer disease, renal insufficiency, and use of nonsteroidal anti-inflammatory drugs, were excluded. MAIN OUTCOME MEASURE: All-cause mortality according to aspirin use. RESULTS: During 3.1 years of follow-up, 276 patients (4.5%) died. In a simple univariable analysis, there was no association between aspirin use and mortality (4.5% vs 4.5%). However, after adjustment for age, sex, standard cardiovascular risk factors, use of other medications, coronary disease history, ejection fraction, exercise capacity, heart rate recovery, and echocardiographic ischemia, aspirin use was associated with reduced mortality (hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.51-0.87; P =.002). In further analysis using matching by propensity score, 1351 patients who were taking aspirin were at lower risk for death than 1351 patients not using aspirin (4% vs 8%, respectively; HR, 0.53; 95% CI, 0.38-0.74; P =.002). After adjusting for the propensity for using aspirin, as well as other possible confounders and interactions, aspirin use remained associated with a lower risk for death (adjusted HR, 0.56; 95% CI, 0.40-0.78; P<.001). The patient characteristics associated with the most aspirin-related reductions in mortality were older age, known coronary artery disease, and impaired exercise capacity. CONCLUSION: Aspirin use among patients undergoing stress echocardiography was independently associated with reduced long-term all-cause mortality, particularly among older patients, those with known coronary artery disease, and those with impaired exercise capacity.

Profile and prevalence of aspirin resistance in patients with cardiovascular disease.

We determined the prevalence and clinical predictors of aspirin resistance by prospectively studying 325 patients with stable cardiovascular disease who were receiving aspirin (325 mg/day for > or =7 days) but no other antiplatelet agents. We also compared the detection of aspirin resistance with optical platelet aggregation, a widely accepted method, with a newer, more rapid method, the platelet function analyzer (PFA)-100, a whole blood test that measures platelet adhesion and aggregation ex vivo. Blood samples were analyzed in a blinded fashion for aspirin resistance by optical aggregation using adenosine diphosphate (ADP) and arachidonic acid, and by PFA-100 using collagen and/or epinephrine and collagen and/or ADP cartridges to measure aperture closure time. Aspirin resistance was defined as a mean aggregation of > or =70% with 10 microM ADP and a mean aggregation of > or =20% with 0.5 mg/ml arachidonic acid. Aspirin semiresponders were defined as meeting one, but not both of the above criteria. Aspirin resistance by PFA-100 was defined as having a normal collagen and/or epinephrine closure time (< or =193 seconds). By optical aggregation, 5.5% of the patients were aspirin resistant and 23.8% were aspirin semiresponders. By PFA-100, 9.5% of patients were aspirin resistant. Of the 18 patients who were aspirin resistant by aggregation, 4 were also aspirin resistant by PFA-100. Patients who were either aspirin resistant or aspirin semiresponders were more likely to be women (34.4% vs 17.3%, p = 0.001) and less likely to be smokers (0% vs 8.3%, p = 0.004) compared with aspirin-sensitive patients. There was a trend toward increased age in patients with aspirin resistance or aspirin semiresponders (65.7 vs 61.3 years, p = 0.06). There were no differences in aspirin sensitivity by race, diabetes, platelet count, renal disease, or liver disease.

Bypass surgery versus coronary angioplasty for revascularization of treated diabetic patients.

BACKGROUND: The purpose of this study was to evaluate outcomes after coronary bypass surgery versus coronary angioplasty in 525 patients with pharmacologically treated diabetes. Diabetic patients constitute a significant portion of patients considered for coronary revascularization. Some studies have shown no difference in long-term outcome when comparing revascularization mode. Recently, the Bypass Angioplasty Revascularization Investigation reported better survival with bypass surgery over angioplasty in treated diabetic patients. However, the above studies have been limited by small cohorts of diabetic patients. METHODS AND RESULTS: By using a single-institution comprehensive database, a retrospective cohort design was used to study 525 consecutive pharmacologically treated diabetic patients who underwent coronary revascularization. Patients treated with surgery (n=246) were statistically similar when comparing age, gender, angina class, and ejection fraction to patients (n=279) treated with angioplasty. Follow-up was complete in 95% of bypass patients and 99% of angioplasty patients. Mean follow-up was 55.5 months. Complete revascularization was accomplished more often in the surgery group (79%) than in the angioplasty group (42%; P<.001). During a 6-year follow-up, repeat revascularization (8% versus 64%; P=.001), cardiac events (32% versus 41%; P=.04), and death (30% versus 37%; P=.08) occurred less in the bypass patients than the angioplasty patients. Multivariable analysis identified age >70 years, ejection fraction <40%, class IV angina, and incomplete revascularization, but not mode of revascularization, as correlates of late mortality. CONCLUSIONS: For most pharmacologically treated diabetic patients, freedom from death, myocardial infarction, and subsequent revascularization during long-term follow-up is superior with bypass surgery compared with angioplasty. This worse outcome was mediated in part by the frequent occurrence of incomplete revascularization with angioplasty.