Cardiac Stress Test and Risk of Death in Patients with Chagas Cardiomyopathy and Left Ventricular Dysfunction

Introduction: Chagas disease has multiple presentations, and only 10% progress to left ventricular (LV) dysfunction. The cardiac stress test (CST) has been underutilized as a prognostic tool for this disease. The objective of this work was to study the main prognostic variables of CST in Chagas cardiomyopathy with LV dysfunction using all-cause death as the endpoint.Methods: This was a prospective cohort study. The CST was performed with the modified Bruce protocol and passive recovery after exertion. The variables analyzed in the CST were stress time, chronotropic index, heart rate recovery (HRR), systolic blood pressure (SBP) recovery, SBP curve on stress, and electrocardiographic changes. We used Cox regression analysis to determine the risk of death after adjusting for demographic variables, cardiovascular risk factors, medications, and LV ejection fraction.Results: A total of 46 patients were eligible. The mean age was 57.70 (SD 9.22) years; 25 (54.3%) were women, and 42 (91.3%) were using beta-blockers. Fourteen (30.4%) deaths were recorded during the total follow-up period of 68 months. Only two variables of the CST were independently associated with the risk of death: time of exercise > 6.5 minutes (HR = 0.286; 95%CI 0.086–0.952; p = 0.041) and HRR ≥ 8 bpm (HR = 0.146; 95%CI 0.036–0.585; p = 0.007).Conclusion: CST proved to be a useful prognostic tool in Chagas cardiomyopathy with LV dysfunction in terms of stress time and HRR.