Predictors of mortality in patients with Chagas' cardiomyopathy and ventricular tachycardia not treated with implantable cardioverter-defibrillators

Abstract

Background: The natural history of the arrhythmogenic form of Chagas' heart disease is not fully understood.

Methods: We assessed the outcome of 56 patients with Chagas' cardiomyopathy ([31 men]; mean age of 55 years; mean left ventricular ejection fraction [LVEF] 42%) presenting with either sustained ventricular tachycardia (VT) or nonsustained VT (NSVT), before therapy with implantable cardioverter-defibrillator was available at our center.

Results: Over a mean follow-up of 38 ± 16 months (range, 1-61 months), 16 patients (29%) died, 11 due to sudden cardiac death (SCD), and five from progressive heart failure. Survivors and nonsurvivors had comparable baseline characteristics, except for a lower LVEF (46 ± 7% vs 31 ± 9%, P < 0.001) and a higher New York Heart Association class (P = 0.003) in those who died during follow-up. Receiver-operator characteristic curve analysis showed that an LVEF cutoff value of 38% had the best accuracy for predicting all-cause mortality and an LVEF cutoff value of 40% had the best accuracy for prediction of SCD. Using the multivariate Cox regression analysis, LVEF < 40% was the only predictor of all-cause mortality (hazard ratio [HR] 12.22, 95% confidence interval [CI] 3.46-43.17, P = 0.0001) and SCD (HR 6.58, 95% CI 1.74-24.88, P = 0.005).

Conclusions: Patients with Chagas' cardiomyopathy presenting with either sustained VT or NSVT run a major risk for mortality when had concomitant severe or even moderate LV systolic dysfunction.