Diagnosis of Chagas Disease: Are Clinical Definitions of Heart Involvement Accurate Enough?

Chronic Chagas cardiomyopathy (CCC) represents the most serious manifestation of the chronic phase of Chagas disease. Currently diagnosis of CCC is based on typical electrocardiogram (ECG) abnormalities in patients with positive Trypanosoma cruzi serology. Regarding CCC severity stratification, there are five different classifications: Kuschnir, Brazilian Consensus on Chagas Disease, modified Los Andes classification, Latin American Guidelines, and American Heart Association (AHA) Statement. Each one includes information about ECG, chest X-ray, echocardiogram, and clinical symptoms of heart failure to stratify patients according to prognosis. In the last decades, new imaging techniques like speckle-tracking echocardiography and magnetic resonance, and some biomarkers have demonstrated higher sensitivity to detect early myocardial involvement as compared with ECG and regular echocardiography. However, there are scarce data about the prognostic impact of this early findings and availability is limited. For these reasons, in endemic countries, ECG remains the main exam to screen for CCC and left ventricular ejection fraction by echocardiogram continues to be the most important marker of global prognosis.