Most cases of sudden cardiac death are attributed to sustained ventricular tachyarrhythmias (VTs), triggered by acute coronary occlusion. Autonomic dysfunction, an important arrhythmogenic mechanism in this setting, is being actively investigated, aiming at the advent of preventive strategies. Recent experimental studies have shown vagal withdrawal after anterior myocardial infarction, coinciding with high incidence of VTs, followed by more gradual sympathetic activation coinciding with a second arrhythmia peak. This article summarizes recent knowledge on this intriguing topic, generating hypotheses that can be investigated in future experimental and clinical studies.
Keywords: Acute myocardial infarction; Arrhythmogenic mechanisms; Delayed arrhythmogenesis; Early arrhythmogenesis; Sudden cardiac death; Sympathetic activity; Vagal activity; Ventricular fibrillation; Ventricular tachyarrhythmias; Ventricular tachycardia.