Mapeamento endocárdico e epicárdico para a ablação do substrato arritmogênico de pacientes com cardiomiopatia chagásica e ta­ quicardia ventricular refratária ao tratamento farmacológico Epicardial and endocardial mapping for arrhythmogenic substrate catheter ablation in patients with Chagas cardiomyopathy and refractory ventricular tachycardia

Objective: Assess the safety and efficacy of endocardial and epicardial substrate catheter mapping and ablation of refractory ventricular tachycardia in patients with Chagas Disease. Patients and Methods: 34 patients were included in this study. During sinus rhythm, patients underwent epicardial and endocardial voltage electroanatomic mapping (CARTO) using standardized criteria (scar < 1.5 mV). Programmed ventricular stimulation was used to induce ventricular tachycardia and stable rhythms were submitted to activation and entrainment mapping. Exit of unstable arrhythmias was defined by stimulation and mapping (pace-mapping) in the scar border zone. Ablation was performed after definition of the circuit and substrate by the reported techniques. Results: 34 procedures were performed and immediate success was achieved in 79%. Epicardial scar was observed in 88%. There was no cardiac tamponade or major complications related to the procedure. During the 12 month follow-up the recurrence rate was 15% in the patients without ventricular tachycardia induction and three patients died due to progressive heart failure. Conclusion: In the study population, catheter ablation using epicardial and endocardial approach was safe and effective in ventricular tachycardia control in chagasic patients.