Epicardial and Endocardial Ablation Based on Channel Mapping in Patients With Ventricular Tachycardia and Chronic Chagasic Cardiomyopathy: Importance of Late Potential Mapping During Sinus Rhythm to Recognize the Critical Substrate

Abstract

Background Ventricular tachycardia (VT) in patients with chronic chagasic cardiomyopathy (CCC) is associated with considerable morbidity and mortality. Catheter ablation of VT in patients with CCC is very complex and challenging. The main goal of this work was to assess the efficacy of VT catheter ablation guided by late potentials (LPs) in patients with CCC. Methods and Results Seventeen consecutive patients with refractory VT and CCC were prospectively included in the study. Combined endo‐epicardial voltage and late activation mapping were obtained during baseline rhythm to define scarred and LP areas, respectively. The end point of the ablation procedure was the elimination of all identified LPs. Epicardial and endocardial dense scars (<0.5 mV) were detected in 17/17 and 15/17 patients, respectively. LPs were detected in the epicardial scars of 16/17 patients and in the endocardial scars of 14/15 patients. A total of 63 VTs were induced in 17 patients; 22/63 (33%) were stable and entrained, presenting LPs recorded in the isthmus sites. The end point of ablation was achieved in 15 of 17 patients. Ablation was not completed in 2 patients because of cardiac tamponade or vicinity of the phrenic nerve and circumflex artery. Three patients (2 with unsuccessful ablation) had VT recurrence during follow‐up (39 months). Conclusions Endo‐epicardial LP mapping allows us to identify the putative isthmuses of different VTs and effectively perform catheter ablation in patients with CCC and drug‐refractory VTs.

Ventricular tachycardia in Chagas disease patients: Our worst nightmare

“…15 Similarly, in a different series from the same group, 14 out of 17 patients (82%) remained free of VT during a follow-up period of 39 ± 11 months after the elimination of all epicardial and endocardial late potentials. 16 Our research group conducted a randomized trial demonstrating the superiority of combined epicardial and endocardial mapping and ablation over endocardial-only approach. 17 Acute success, defined as non-inducibility of clinical VT, was achieved in 13 patients (86%) in the endo/epi group compared to 6 patients (40%) in the endo-only group (p = .021).…”

“…In one series, which involved simultaneous epicardial and endocardial mapping and ablation in 17 Chagas disease patients, successful ablation was achieved in 11 out of 14 patients (78.6%), resulting in no VT recurrence during a mean follow‐up of 318 ± 95 days 15 . Similarly, in a different series from the same group, 14 out of 17 patients (82%) remained free of VT during a follow‐up period of 39 ± 11 months after the elimination of all epicardial and endocardial late potentials 16 …”