Prior myocarditis and ventricular arrhythmias: the importance of scar pattern

Abstract Background : multiple studies have already addressed the importance of anteroseptal scar in patients with non-ischemic cardiomyopathy. However, this pattern has never been fully evaluated in patients with prior myocarditis. Objective : to evaluate if anteroseptal scar is associated with worse outcome in patients with prior myocarditis and how does it affect the efficacy of catheter ablation (CA). Methods : this is a retrospective study of consecutive patients, with prior myocarditis and arrhythmic presentation. Cardiac magnetic resonance (CMR) and electro-anatomic voltage mapping (EVM) were used to identify the scar pattern. Patients were referred for either CA or escalated antiarrhythmic drugs (AADs). Main outcome was ventricular arrhythmias (VAs) free-survival according to the presence of anteroseptal scar. Results : a total of 144 consecutive patients with prior myocarditis were included. Mean age was 42.1±14.9 years and 58% were men. Ejection fraction was normal in 73% of patients. Anteroseptal scar was present in 44% of cases. Sixty-one patients (42%) underwent CA. Overall, at two-year follow-up, VA-free survival was 77% in the CA group. After CA, the mean number of AAD each patient took dropped from 1.8 to 0.9/die (p Conclusions In patients with prior myocarditis and VA, the presence of anteroseptal scar negatively predicts outcomes irrespective of the treatment strategy.