Clinical predictors of inducible sustained ventricular tachycardia during electrophysiologic study in patients with chronic Chagas' heart disease

BackgroundClinical independent predictors of inducible sustained ventricular tachycardia (VT) during electrophysiologic study (EPS) are not known in patients with chronic Chagas' heart disease. The purpose of this investigation was to fill this gap.MethodsThe medical charts of 47 patients with a positive serology for Chagas' disease who had undergone EPS between September 2006 and July 2012 at our institution were reviewed. Reasons for the EPS were the presence of unexplained syncope, non-sustained ventricular tachycardia (NSVT) on either resting ECG or 24 h-Holter monitoring as well as a LVEF < 55% and > 35% at echocardiography. A stepwise logistic regression analysis was performed to identify noninvasive predictors of inducible sustained VT/ventricular fibrillation during EPS.ResultsOn univariate analysis, syncopal episodes (p = 0.04), amiodarone therapy (p < 0.005), diastolic blood pressure (p = 0.03), creatinine serum levels (p < 0.001), potassium serum levels (p < 0.001), and lengthening of the QRS complex (p = 0.03) were associated with inducible sustained VT during EPS. In the multivariate model, amiodarone therapy (p = 0.03; hazard ratio = 10; Wald coefficient = 4.5; 95% confidence interval 1.2 to 85.2) was the only variable retained as independent predictor of inducible sustained VT during EPS.ConclusionAmiodarone therapy was the only independent variable associated with sustained VT inducibility during EPS in patients with chronic Chagas' heart disease.