A COMPOSITE VIEW OF CARDIAC RUPTURE IN THE UNITED-STATES NATIONAL REGISTRY OF MYOCARDIAL-INFARCTION

Objectives. This study was done to determine the incidence, timing and prevalence as a cause of death from cardiac rupture in patients with acute myocardial infarction. Background. Several clinical trials and o verview analyses have suggested that the survival benefit conferred by thrombolytic therapy may be offset by a paradoxic increase in early d eaths from cardiac rupture. Methods. Demographic, procedural and outco me data from patients with acute myocardial infarction were collected at 1,073 United States hospitals collaborating in the United States Na tional Registry of Myocardial Infarction. Results. Among the 350,755 p atients enrolled, 122,243 received thrombolytic therapy. In-hospital m ortality for the overall patient population, those not treated with th rombolytics (n = 228,512) and those given thrombolytics mere 10.4%, 12 .9% and 5.9%, respectively (p < 0.001). Cardiogenic shock was the most common cause of death in each patient group. Although the incidence o f cardiac rupture was low (<1.0%), it was responsible for 7.3%, 6.1% a nd 12.1%, respectively, of in-hospital deaths (p < 0.001), Death from rupture occurred earlier in patients given thrombolytic therapy, with a clustering of events within 24 h of drug administration. Despite the early risk, death rates mere comparatively low in thrombolytic-treate d patients on each of the first 30 days. By multivariable analysis, th rombolytics, prior myocardial infarction, advancing age, female gender and intravenous betablocker use were independently associated with ca rdiac rupture. Conclusions. This large registry experience, including over 350,000 patients with myocardial infarction, suggests that thromb olytic therapy accelerates cardiac rupture, typically to within 24 to 48 h of treatment. The possibility that rupture represents an early he morrhagic complication of thrombolytic therapy should be investigated.