The Migration of Chagas Disease

Description of Clinical Presentation: A 42-year-old female seen by a cardiologist in the Washington, DC metropolitan area was referred for evaluation of cardiomyopathy (CM). Of note, she was from El Salvador. She was doing well until the past several months in which the patient reported feeling frequent palpitations and increasing shortness of breath. A transthoracic echocardiogram revealed an estimated ejection fraction (EF) of 40-45% and mildly dilated left ventricle (LV). The patient was referred to CMR to identify an etiology of her CM.

Diagnostic Techniques and Their Most Important Findings: Sequences of CMR included cine steady-state free precession (SSFP) for ventricular function, T2 mapping for myocardial edema, pre and post-contrast T1 mapping with extracellular volume fraction (ECV), and late gadolinium enhancement (LGE) for fibrosis detection.

The CMR revealed a moderately dilated LV with a moderately reduced EF of 38%. An LV apical aneurysm (Fig 1.) was present with transmural LGE, accompanied by global hypokinesis. Additionally, there was patchy LGE within the basal to mid lateral wall (Fig 2.)

Learning Points from this Case: These findings and the patient’s background history prompted serologic testing and confirmation for Chagas disease. Chagas CM is a chronic complication of Trypanosoma cruzi infection, often presenting decades after initial exposure, affecting 8 million people worldwide but particularly in Latin American countries.¹ Cardiovascular complications are the leading cause of death with CM affecting 20-30% of affected patients. Heart failure, ventricular aneurysms, and thrombo-embolic complications may be seen in advanced stages of the disease. CMR plays a critical role in diagnosis and risk stratification by providing detailed evaluation of myocardial morphology, function, and tissue characterization.² Classic CMR findings include fibrosis, often involving the inferolateral and apical segments, which often correlates with arrhythmic risk, development of aneurysm, and disease progression. Chagas-related fibrosis is not confined to a single coronary distribution but may be patchy and irregular and associated with T1, T2, and ECV abnormalities. Quantitative mapping techniques enhance sensitivity for diffuse fibrosis, which may precede overt functional decline.

A key point to recognize is that with migration, Chagas disease is now an emerging cause of CM in non-endemic countries.³ Cardiologists need to recognize the potential risk of Chagas CM in patients who present from countries endemic to Chagas disease. Early recognition along with the robust ability of CMR imaging may help to mitigate more advanced complications of the disease process.

Figure 1. Apical aneurysm shown in diastole and systole of 4chamber cine (red arrows).
Figure 2. On the top row, lateral wall LGE can be seen, confirmed with a dark blood acquisition. On the bottom row, the enhanced apical aneurysm is apparent (red arrows).