Abstract 15177: Speckle-Tracking Echocardiography Improves Risk Stratification in Patients With Chagas Cardiomyopathy

Abstract

Introduction: Chagas cardiomyopathy is an important cause of death in endemic areas. Speckle-tracking echocardiography (STE)-derived strain is a sensitive tool for evaluating myocardial function which may be helpful to improve risk stratification of Chagas cardiomyopathy patients. This study evaluated whether STE has incremental value for prognosis over traditional clinical and echocardiographic parameters in patients with Chagas cardiomyopathy. Methods: Patients with Chagas disease who had evidence of heart failure were selected for the study. Clinical evaluation, electrocardiogram (ECG), and echocardiogram were performed at the time of enrollment. STE-derived global longitudinal strain (GLS) was analyzed offline. The outcome was all-cause mortality. Results: A total of 317 patients were enrolled, mean age was 66 ± 13 years and 184 (58%) were women. During a mean follow-up of 2.6 years, 114 patients died (36%) with overall mortality incidence rate of 14.0 deaths per 100 patient-years (95% CI 11.6-16.8). GLS was an important predictor of death (HR 0.90; 95% CI 0.86 to 0.95; P<0.001), adding incremental prognostic value to standard echocardiographic parameters including right ventricular (RV) end-diastolic area, E/e’ ratio, left atrial (LA) volume, and left ventricular ejection fraction (LVEF). In overall population, the model including GLS had better accuracy in predicting mortality than the model including only conventional echocardiographic variables (P = 0.015). When the patients were stratified according to LVEF, GLS provided incremental prognostic information in patients with preserved (n=84; HR 0.80; 95% CI 0.64 to 0.98) or with mild to moderate reduced LVEF (n=166; HR 0.92; 95% CI 0.85 to 0.98), whereas in those who had severe LV dysfunction (n=67), GLS was no longer associated with mortality. Conclusions: In a cohort of patients with Chagas cardiomyopathy living in remote areas, GLS was a strong predictor of death, improving risk stratification beyond that provided by standard echocardiographic measurements, especially in patients with non-severe LV dysfunction. STE assessment may be used in a clinical setting to improve the risk prediction model for mortality in patients with Chagas cardiomyopathy.