PREDICTORS OF IN-HOSPITAL AND 6-MONTH OUTCOME AFTER ACUTE MYOCARDIAL-INFARCTION IN THE REPERFUSION ERA - THE PRIMARY ANGIOPLASTY IN MYOCARDIAL-INFARCTION (PAMI) TRIAL

Objectives. This study examined the predictors of in-hospital and 6-mo nth outcome after different reperfusion strategies in acute myocardial infarction. Background. Thrombolytic therapy and primary angioplasty are both widely applied as reperfusion modalities in patients with myo cardial infarction. Although it is accepted that restoration of early patency of the infarct related artery can reduce mortality and salvage myocardium, the optimal reperfusion strategy remains controversial, a nd the predictors of outcome in the reperfusion era have been incomple tely characterized. Methods. At 12 centers, 395 patients presenting wi thin 12 h of onset of acute transmural myocardial infarction were pros pectively randomized to receive tissue type plasminogen activator (t-P A) or undergo primary angioplasty without antecedent thrombolysis. Six teen clinical variables were examined with univariate and multiple log istic regression analysis to identify the predictors of clinical outco me. Results. By univariate analysis, in-hospital mortality was increas ed in the elderly, women, patients with diabetes and in patients treat ed with t-PA as opposed to angioplasty. Only advanced age and treatmen t by t-PA versus angioplasty independently correlated with increased i n-hospital mortality (6.5% vs. 2.6%, respectively, p = 0.039 by multip le logistic regression analysis). Similarly, the only variables indepe ndently related to in-hospital death or nonfatal reinfarction were adv anced age and treatment by t-PA versus angioplasty (12.0% vs. 5.1%, p = 0.02). The reduction in in-hospital death or reinfarction with angio plasty versus t-PA was particularly marked in patients greater than or equal to 65 years of age (8.6% vs. 20.0%, p = 0.048). Furthermore, pr imary management with angioplasty versus t-PA was the most powerful mu ltivariate correlate of freedom from recurrent ischemic events (10.3% vs. 28.0%, p = 0.0001). The independent beneficial effect of angioplas ty on freedom from death or reinfarction was maintained at 6-month fol low-up (8.2% vs. 17.0%, p = 0.02). Conclusions. In the reperfusion era , the two most powerful determinants of freedom from death, reinfarcti on and recurrent ischemia after myocardial infarction are young age an d treatment by primary angioplasty.