Factors that predict ventricular arrhythmias in the late phase after acute myocardial infarction

Abstract

Aims: Little is known regarding factors that predict the occurrence of lethal ventricular arrhythmias (VAs) occurring after acute myocardial infarction (AMI). This observational cohort study aimed to identify factors that predicted lethal VAs during the late phase after AMI in patients with reduced left ventricular ejection fraction (LVEF).

Methods and results: Data were collected from our AMI database regarding consecutive patients with an LVEF of ≤40% after AMI (January 2012 to July 2018). The 'late phase' was defined as ≥7 days after AMI onset, and the primary endpoint was defined as lethal VAs in the late phase. The study included 136 patients (82% men; mean age: 66 ± 13 years). The average LVEF at admission was 32.7 ± 8.2%. During a mean follow-up period of 20.7 months, 14 patients (10%) experienced lethal VAs, including ventricular fibrillation (n = 8) and sustained ventricular tachycardia (n = 10). Univariate analyses revealed that lethal VAs were predicted by age and LVEF at admission. Receiver operating characteristic curve analysis indicated that the optimal cut-off value was 23% for using the LVEF at admission to predict the primary endpoint (area under the curve: 0.77, P < 0.0001). Multivariable analysis also demonstrated that LVEF at admission was an independent predictor of the primary endpoint (risk ratio = 7.12, P = 0.001).

Conclusions: Lethal VAs in the late phase are common in patients with AMI, and reduced LVEF and cardiac function at admission play a significant role in the risk stratification for future lethal VAs in this population.

Keywords: Myocardial infarction; Reduced left ventricular ejection fraction; Ventricular arrhythmia.