Outcome of contemporary acute coronary syndrome complicated by ventricular tachyarrhythmias

Abstract

Aim: To evaluate the incidence and prognostic implications of ventricular tachyarrhythmias (VTAs) complicating acute myocardial infarction (MI).

Methods and results: We evaluated 7669 MI patients [ST elevation (n = 3573) and non-ST-elevation acute coronary syndrome (ACS) (n = 4096)] from the Acute Coronary Syndrome Israeli Survey for the incidence of VTA. Ventricular tachyarrhythmia occurred in 3.8% of patients [2.1% early (≤ 48 h) and 1.7% late (>48 h) VTA]. In-hospital mortality rates were higher for patients with VTA when compared with patients with no VTA (P < 0.001). Consistent with these findings, multivariable analysis demonstrated that early and late VTAs were associated with increased risk of in-hospital death [hazard ratio (HR) = 3.84; 95% confidence interval (CI) 1.77-6.78, P < 0.001, and HR = 8.23; 95% CI 4.84-13.98, P < 0.001, respectively]. In contrast, post-discharge outcomes demonstrated that only late VTA was independently associated with a significant increased risk of 30-day mortality (HR = 5.17; 95% CI 1.54-17.27, P = 0.007) with a trend towards an increased 1-year mortality risk (HR = 1.69; 95% CI 0.79-3.62, P = 0.17). The long-term risk associated with in-hospital VTA was driven by sustained ventricular tachycardia (VT) (HR = 3.28; 95% CI 1.92-5.60, P < 0.001) but not ventricular fibrillation (HR = 1.27; 95% CI 0.65-2.49, P = 0.47).

Conclusions: Our findings suggest that in patients with ACS, both early and late VTAs are associated with an increased risk of in-hospital mortality. However, only late VTA, mostly sustained VT, is associated with long-term adverse outcome.

Keywords: ACSIS registry; Acute coronary syndrome; Acute myocardial infarction; Outcome; Ventricular fibrillation; Ventricular tachycardia.