Evaluation of syncope in patients with chronic Chagas heart disease

To evaluate causes of syncope in patients with Chagas' disease and intraventricular conduction disturbances. Nine patients have been studied, being seven males. Average of 49 years. The studied consisted of His Bundle electrogram, determination of Wenckebach period (WP), sinus node recovery time (SNRT), atrial stability and programmed ventricular stimulation (PVS). Monomorphic ventricular tachycardia (VT) was induced in five patients (55.5%), WP depression was observed in three cases, H-V interval prolongation occurred in three cases and the SNRT was normal in hall patients. In one case the electrophysiological study was completely normal. Among five patients with induced VT, with a mean follow-up period of seven months, one died suddenly, three became asymptomatic with antiarrhythmic drugs and one went on a non pharmacological therapy. In the other four patients with a mean follow-up period of 21 months, three are asymptomatic and one presents occasional dizziness (patient with a normal study). Among the patients with VT four presented recurrent syncope while in the group of patients without VT (four patients) all had only one syncopal episode. Patients with intraventricular disturbances, Chagas' disease and syncope, VT may be responsible for the symptoms in approximately 44% of cases. The PVS must be considered as a routine in the investigation of these patients.