Support for the open-artery hypothesis in survivors of acute myocardial infarction: Analysis of 11,228 patients treated with thrombolytic therapy

We examined the possible benefits of achieving and maintaining infarct-rela ted artery potency beyond the time when preservation of left ventricular fu nction would be expected. The open-artery hypothesis suggests that a patent infarct-related artery confers a survival benefit greater than that expect ed from myocardial salvage alone, which extends beyond the time when preser vation of left ventricular function is expected. We examined the survival e xperience of patients undergoing thrombolysis in the Global Utilization of Streptokinase and TPA for Occluded Arteries (GUSTO-I) trial for whom data o n the potency of the infarct artery were available. Univariable analysis wa s used to determine the unadjusted relations of angiographic variables and revascularization procedures to both 30-day and 1-year mortality in 30-day survivors. Multivariable analysis was used to test far interactions between patency and each characteristic and to adjust both for all other variables and for baseline characteristics known to predict mortality, In both univa riable and multivariable analysis, patients with an open rather than a clos ed infarct-related artery had significantly lower 30-day mortality (p <0.00 1), This benefit cannot be accounted for by myocardial salvage alone, becau se it remained after adjustment for left ventricular ejection fraction. Pat ency was also associated with lower 1-year mortality in 30-day survivors, b ut not after adjustment for other variables affecting late mortality. Havin g an open infarct-related artery at the time of first catheterization confe rs a survival advantage that extends beyond the benefit of myocardial salva ge from thrombolytic therapy, and is independent of election fraction. (C) 1999 by Excerpta Medico, Inc.