Ventricular arrhythmia-heart failure interaction and mortality in ICD recipients after myocardial infarction.

Abstract

Aims: Ventricular arrhythmia (VA) and heart failure (HF) frequently coexist in patients with ischaemic left ventricular (LV) dysfunction. Whether VA and HF events are bidirectionally associated remains unclear. We investigated their bidirectional relationship and associations with mortality.

Methods: We analysed 1014 patients from the multicentre WICD-MI study. All received a wearable cardioverter-defibrillator after acute myocardial infarction (MI) and subsequently underwent implantable cardioverter-defibrillator (ICD) implantation, with persistent LV ejection fraction ≤35%. Associations between ICD-treated VA, HF-events (HF hospitalization, heart transplantation, or LV assist device implantation), and all-cause mortality were assessed using time-dependent Cox models.

Results: Over a median follow-up of 2.6 years post-ICD implantation, VA was independently associated with an increased risk of HF events [aHR = 3.50 (1.66-7.38), P = .001], while HF events similarly preceded subsequent VA [aHR = 2.96 (1.59-5.50), P = .0008]. Both were independently associated with all-cause mortality, with a numerically higher aHR for HF events [aHR = 7.96 (4.71-13.47), P < .0001] than for VA [aHR = 4.43 (2.35-8.36), P < .0001]. Sensitivity analyses suggested that the VA-HF association was strongest for shock-treated arrhythmias. In exploratory analyses, VA was strongly associated with subsequent HF events in subcutaneous ICD recipients [aHR = 15.08 (4.62-49.22), P < .0001] but not in transvenous ICD recipients (P for interaction = .0002).

Conclusion: In ICD recipients with persistent LV dysfunction following MI, VA and HF events are bidirectionally associated and independently associated with mortality. The VA-HF association was strongest for shock-treated arrhythmias. These findings highlight the potential value of integrated HF and VA management.