Sustained ventricular arrhythmias and mortality among patients with acute myocardial infarction: results from the GUSTO-III trial.

Background: In many patients, ventricular arrhythmias will develop early after acute myocardial infarction. We studied the incidence, timing, and outcomes of such arrhythmias in the international Global Utilization of Streptokinase and TPA (alteplase) for Occluded Coronary Arteries (GUSTO)-III trial.

Methods: We identified independent predictors of inhospital ventricular fibrillation (VF) and ventricular tachycardia (VT) and compared 30-day and 1-year mortality rates of patients who did (n = 1121) and did not (n = 13,921) have these arrhythmias during the index hospitalization.

Results: Significant independent predictors of inhospital VF were higher Killip class, lower baseline systolic pressure, intravenous preenrollment lidocaine use, shorter time to thrombolysis, and beta-blocker use <2 weeks before enrollment; independent predictors of inhospital VT were lower baseline systolic pressure, intravenous lidocaine use before enrollment, higher Killip class, faster baseline heart rate, and advanced age. The 30-day mortality rate was 31% in patients with VF, 24% in those with VT, 44% in those with both, and 6% in those with neither (P =.001). The corresponding 1-year mortality rates were 34%, 29%, 49%, and 9% (P =.001). The 30-day and 1-year mortality rates were higher for patients with late (>48 hours after enrollment) versus early arrhythmias (< or =48 hours after enrollment).

Conclusions: Despite thrombolysis, inhospital ventricular arrhythmias are associated with higher 30-day and 1-year mortality rates after acute myocardial infarction, particularly when occurring later during the initial hospitalization. Better therapies are needed to improve outcomes of these arrhythmias.