Etiology influence in mortality on Heart Failure with Preserved Systolic Function on a high prevalence Chagas heart disease population.

Background: Heart Failure with Preserved Systolic Function is a clinical syndrome that has the same signs and symptoms of classic heart failure. Aim: To compare the clinical features and evolution of Heart Failure (HF) in patients with systolic dysfunction and preserved systolic function (PSF) on a high prevalence Chagas heart disease population. Methods: We prospectively evaluated patients with clinical diagnosis of HF admitted at a reference clinic in Salvador-BA (Brazil). PSF was considered as heart failure with left ventricle ejection fraction (LVEF) greater than 45% analyzed by echocardiography. One year follow-up was obtained through phone contact or personal interview at the cardiac failure clinic. Results: During a 16 months period of time, 383 patients were included, 52.5% were male and mean age was 54.2 years. PSF was observed in 138 patients (36%). The main etiology for both types of HF was Chagas disease (45.3% in systolic dysfunction and 44.2% in PSF). One-year follow-up was obtained in 358 patients (93.5%). Patients with Chagas disease and PSF had a lower mortality rate when compared with patients with systolic dysfunction (10% vs. 23.6%; p=0,039). In patients without Chagas disease and PSF mortality was similar to those with systolic dysfunction (10.4% vs. 15.8%; p=0,307). Conclusions: PSF was commonly found in our population. Chagas disease is the main etiology of HF regardless of LVEF. Patients with Chagas disease and PSF have a better prognosis than those with systolic dysfunction, probably because the formers have initial cardiac impairment.