Importance of Right Ventricular Mapping and Ablation for Ventricular Tachycardia in Postinfarction Patients.

BACKGROUND

The characteristics of patients with post-myocardial infarction (PMI) ventricular tachycardia (VT) who require right ventricular (RV) ablation are underreported.

OBJECTIVES

The aims of this study were to examine the characteristics and outcomes of patients undergoing PMI VT ablation who have target sites in the right ventricle and to compare patient and VT characteristics between patients with free wall vs septal RV target sites.

METHODS

Consecutive patients undergoing ablation for PMI VT with target sites located within the right ventricle were included. Patients were stratified on the basis of the presence of free wall vs septal RV target sites.

RESULTS

Among 277 consecutive patient undergoing PMI VT ablation, 30 (11%) had RV target sites (mean age 68.71 ± 9.5 years, 29 men [97%], mean left ventricular ejection fraction [LVEF] 28.7% ± 16.7%). Twenty patients had only septal VTs, and 10 patients had only free wall VTs. Fifty-seven VTs with RV targets (1.9 ± 1.4 per patient, mean cycle length 338 ± 90 ms, 53 left bundle branch, 36 superior axis) were induced. Patients with RV free wall VTs had greater rates of RV dysfunction (80% vs 30%; P = 0.023) but had greater LVEFs (38.3% ± 21.06% vs 23.9% ± 11.93%; P = 0.02). Over a mean follow-up period of 3.4 ± 3.2 years, patients with RV septal target sites had worse survival free of VT, transplantation, or left ventricular assist device placement after ablation (log-rank P < 0.05).

CONCLUSIONS

The arrhythmogenic substrate in PMI patients often involves the right ventricle, including the septum and free wall. The presence of RV dysfunction and greater LVEF were associated with the presence of RV free wall target sites. Patients with only RV septal target sites had worse postablation outcomes.