Ventricular arrhythmias and haemodynamic collapse during acute coronary syndrome: increased risk for sudden cardiac death?

Abstract

Abstract Aims In the acute phase of acute coronary syndrome (ACS), ventricular tachycardia (VT) and/or ventricular fibrillation (VF) leading to resuscitation are not considered to be associated with increased long-term sudden cardiac death (SCD) because the cause—acute ischaemia—is believed to be reversible. The aim of this study is to investigate whether ventricular arrhythmias (VAs) leading to sudden cardiac arrest during ACS are associated with the risk of incident SCD in patients with a normal or mildly impaired left ventricular ejection fraction (LVEF). Methods and results This study is based on a retrospective analysis of all 8062 consecutive ACS patients undergoing coronary angiography with the baseline LVEF ≥40% between 2007 and 2018 (follow-up until 31 December 2021). The primary outcome was SCD-equivalent life-threatening VAs (LTVAs) composed of true SCDs and SCDs aborted by successful resuscitation or appropriate implantable cardiac device (ICD) therapy. The risk of sudden LTVA was estimated with a multivariate subdistribution hazard model using other deaths as competing events. Two-hundred thirteen (n = 211, 2.6%) patients suffered acute phase VF/VT leading to resuscitation and survived to discharge, and most occurred before angiography (80.6%, n = 170) and were VF (92.9%, n = 196). During a median follow-up of 7.6 years, 3.9% (n = 316) of all the patients had LTVA (10.0% in the VF/VT group vs. 3.8% in other patients). Ventricular fibrillation/VTs during ACS are associated with an increased risk for future SCD (hazard ratio 3.07; 95% confidence interval 1.94–4.85, P < 0.001). Most LTVAs occurred in patients without ICDs. Conclusion Ventricular fibrillation/VT in ACS is associated with a remarkably high long-term risk for SCD in patients with an LVEF ≥40%.