Echocardiographic predictors of mortality in heart failure from Chagas cardiomyopathy: Refining risk stratification with speckle-tracking echocardiography

Background: Chagas cardiomyopathy is a major cause of mortality in endemic regions, predicted primarily by left ventricular (LV) systolic function. Speckle-tracking echocardiography (STE)-derived strain is a sensitive tool for assessing ventricular function and may enhance risk stratification. This study aimed to determine whether STE provides incremental prognostic value beyond traditional echocardiographic parameters in patients with Chagas cardiomyopathy. Methods: Patients with Chagas cardiomyopathy 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, with a mean age was 66 ± 12 years, and 133 (42 %) were male. Over a median follow-up of 2.7 years ([IQR] 1.96-3.50), 114 patients died (36 %). GLS was an important predictor of death (HR 0.88; 95 % CI 0.84 to 0.92; p < 0.001), adding incremental prognostic value beyond standard echocardiographic parameters, including left atrial (LA) volume, E/e' ratio, right ventricular (RV) dimension, and LV ejection fraction. The predictive model incorporating GLS demonstrated superior accuracy for mortality prediction compared to model based on conventional echocardiographic variables. Further stratification by LV ejection fraction revealed that the prognostic utility of GLS was strongest in patients with preserved or mildly reduced systolic function and decreased in those with severe LV dysfunction. Conclusions: In a cohort of patients with heart failure from Chagas cardiomyopathy residing in remote areas, GLS emerged as an independent predictor of mortality, improving risk stratification beyond standard echocardiographic parameters, particularly in patients with early stages of cardiac involvement. STE offers a valuable tool in clinical settings, improving risk assessment and providing guidance for the management of this population.