Catheter Ablation for Ventricular Tachycardia in Patients With Biopsy-Proven Myocarditis.

BACKGROUND

Catheter ablation (CA) is increasingly recognized as an effective treatment for ventricular tachycardia (VT) in myocarditis patients, although current evidence is based on less robust data.

OBJECTIVES

The purpose of this study was to confirm CA's efficacy in reducing VT recurrence and to identify arrhythmic risk factors in biopsy-proven myocarditis patients.

METHODS

In this dual-center, retrospective study, we included 50 patients with biopsy-proven myocarditis and VT. They were divided into 2 groups: CA (n = 23) and non-CA (n = 27), with the primary endpoint being VT recurrence at 1-year follow-up.

RESULTS

The average age of participants was 40.8 ± 14.9 years; 48% were men. Over a median 371-day follow-up, 28 (56%) experienced VT recurrence, with 8 patients (35%) in the CA group and 20 patients (74%) in the non-CA group. Kaplan-Meier analysis showed that the rate of VT recurrence in the CA group was significantly lower than in the non-CA group (log-rank 0.009). However, this difference was not found in patients with acute myocarditis. Multivariable analysis revealed a significant correlation between the acute stage of myocarditis and VT recurrence in both the general cohort (HR: 3.02; 95% CI: 1.11-8.21; 0.031) and the subset undergoing CA (HR: 11.4; 95% CI: 1.02-127.5; 0.048).

CONCLUSIONS

CA is significantly associated with reduced VT recurrence in biopsy-proven myocarditis, albeit this association is not observed in cases of acute myocarditis. The acute stage of myocarditis is independently associated with an increased risk of VT recurrence.