Longitudinal Study of Patients With Chronic Chagas Cardiomyopathy in Brazil (SaMi_Trop Project)

RESEARCH STRATEGY

SIGNIFICANCE

The Sao Paulo-Minas Gerais Tropical Medicine Research Center (SaMi-Trop) consists of a network of collaborating scientists in the States of Minas Gerais and São Paulo which has been established for the purpose of developing and conducting research projects on neglected infectious diseases in Brazil, with an initial focus on Chagas Disease biomarker, discovery and validation. The SaMi-Trop represents a major challenge for focused research in neglected diseases, with knowledge that can be applied in primary health care.

Chronic Chagas Cardiomyopathy (CCC) is the most important clinical presentation of Chagas Disease (ChD), eventually affecting approximately 20% to 30% of those in the chronic phase of the disease. CCC comprises a wide range of manifestations, including heart failure, arrhythmias, heart-blocks, sudden death, thromboembolism and stroke [1]. Clinical presentation typically varies widely according to the degree of myocardial damage and most patients present a mild form of heart disease, frequently characterized only by the presence of asymptomatic abnormalities on the ECG or in other complimentary exams [2]. Nonetheless, when heart failure and/or severe arrhythmias manifest, the prognosis is ominous, with high and premature mortality rates, typically in adult male patients,1 but also in the elderly [3]. Indeed, when compared to patients with idiopathic cardiomyopathy, patients with CCC have poorer survival, irrespective of other clinical and echocardiographic parameters [4].

Thus, the clinical course of Chagas heart disease is variable and identifying patients who are at risk of progressive CCC and dying remains a challenge. Several longitudinal studies performed in patients in the chronic phase of ChD demonstrated that many individual characteristics predict an unfavorable prognosis. This subject was systematically reviewed a few years ago and concluded that most studies were described in insufficient detail and/or lacked minimal standards in reporting results. Results have been somewhat inconsistent in different studies, and the best combination of clinical and laboratory variables predictive of mortality has not yet been established [5].