COMPARISON OF OUTCOME OF PATIENTS WITH UNSTABLE ANGINA AND NON-Q-WAVEACUTE MYOCARDIAL-INFARCTION WITH AND WITHOUT PRIOR CORONARY-ARTERY BYPASS-GRAFTING (THROMBOLYSIS IN MYOCARDIAL-ISCHEMIA-III REGISTRY)

The aim of this study was to characterize patients with and without pr ior coronary artery bypass grafting (CABG) among a prospectively ident ified cohort of patients presenting with unstable angina or non-Q-wave myocardial infarction. Patients in the Thrombolysis in Myocardial Inf arction phase III Registry Prospective Study presented within 96 hours of an episode of unstable angina or non-Q-wave acute myocardial, infa rction. Of 2,048 patients, 336 (16.4%) had prior CABG Compared with th ose without prior CABG, patients were the same age, but were more like ly to be men, white, diabetic, have a history of angina or myocardial infarction, to have received anti-ischemic medications in the prior we ek, and to receive intravenous heparin or nitroglycerin, or bath, duri ng hospitalization. They were equally likely to undergo coronary angio plasty or CABG. Death or nonfatal myocardial infarction occurred by da y 10 in 4.5% of patients with prior CABG and 2.8% of patients without prior CABG (p = 0.11); and by day 42 in 7.7% and 5.1%, respectively (p = 0.03). The composite of death, myocardial infarction, or recurrent ischemia at 1 year was more common among patients with prior CABG (39. 3% vs 30.2%, p = 0.002). By multiple logistic regression, prior CABG w as not independently associated with the occurrence of death or myocar dial infarction, or the composite of death, myocardial infarction, or recurrent ischemia either at 6 weeks or at 1 year. The likelihood of r ecurrent ischemic events is greater among patients with than without p rior CASG, but is most likely explained by differences in baseline or treatment characteristics which reflect the degree of underlying cardi ac disease.