Abstract
BACKGROUND: Cardiac rupture (CR), encompassing both free wall and ventricular septal ruptures, is a serious complication of ST-segment elevation myocardial infarction (STEMI). In this study, we aimed to investigate the incidence, characteristics, and clinical outcomes of CR in patients with STEMI. METHODS AND RESULTS: The Japan Acute Myocardial Infarction Registry (JAMIR) is a multicenter prospective study. Of the 3,411 patients hospitalized with acute MI between 2015 and 2017, data from 2,626 patients with STEMI (612 women [23.3%]; median age, 68 years) were analyzed. CR occurred in 34 patients (1.3%), comprising free wall rupture in 25 cases (73.5%), ventricular septal rupture in 8 cases (23.5%), and both in 1 case (2.9%). Compared to those without CR, the cumulative incidence of the primary endpoints (cardiovascular death, non-fatal MI, or non-fatal stroke) at 1 year was significantly higher in the CR group (64.7% vs. 7.9%, log-rank P<0.001). Factors independently associated with CR included older age, anterior wall infarction, and prolonged onset-to-admission time. Notably, the incidence of CR increased with longer onset-to-admission times (0-3 h, 0.6%; 3-6 h, 1.7%; 6-12 h, 1.7%; ≥12 h, 3.6%; P for trend <0.001), but was not associated with door-to-device times (≤90 min, 0.7% vs. >90 min, 1.4%; P=0.156). CONCLUSIONS: CR following STEMI is associated with delayed onset-to-admission time and poor clinical outcomes.