Prevalence and Prognostic Value of Ventricular Dyssynchrony in Chagas' Cardiomyopathy

Abstract

BACKGROUND: Chagas' cardiomyopathy is one important cause of heart failure in Latin America. Ventricular dyssynchrony may be a factor of decompensation in the course of this disease, but there are no data on its prevalence and its main prognostic implications yet. OBJECTIVE: Describe prevalence and prognostic value of ventricular dyssynchrony in Chagas' cardiomyopathy. METHODS: 56 patients with Chagas' cardiomyopathy were consecutively selected by two positive serologies and an ejection fraction < 45% in the echocardiogram. The echocardiogram evaluated the presence of intraventricular dyssynchrony using 3 criteria and interventricular dyssynchrony using 1 criterion. Patients were followed for 21 ± 14 months and cardiac events were defined as the combination of death and hospitalization. RESULTS: The average age of the population was 56 ± 10 years, 50% males. Mean ejection fraction was 30 ± 8% and 87% presented functional class I/II (NYHA). The prevalence of interventricular dyssynchrony was 34% (95% CI: 22%-48%) and intraventricular dyssynchrony had a prevalence of 85% (95% CI: 75%-93%). The prevalence of intraventricular dyssynchrony was similar among patients with QRS duration < 0.12 s or > 0.12 s (85% and 89%, respectively, p= 0.66). Twenty events were recorded. The incidence of combined events was similar in patients with or without intraventricular dyssynchrony (35% versus 38%, p= 0.9) and those with or without interventricular dyssynchrony (39% versus 34%, p= 0.73). CONCLUSION: Patients with Chagas' cardiomyopathy have high intraventricular and moderate interventricular prevalence of dyssynchrony. The high prevalence is independent from the QRS width. The ventricular dyssynchrony does not have any prognostic value in patients with Chagas' cardiomyopathy.