Eighteen-year prognostic outcomes of acute heart failure resulting from orally transmitted Chagas disease

Background

Chagas disease (ChD), caused by Trypanosoma cruzi, poses a significant public health risk, impacting approximately 6 million individuals globally. Oral transmission is characterized by more severe manifestations than those associated with classical vectorial infection. While substantial data are available regarding the chronic phase, there remains limited understanding of both the acute oral phase and its long-term outcomes.

Purpose

To describe the 18-year follow-up of the largest outbreak of orally acquired ChD, with an emphasis on heart Failure (HF).

Methods

We included 103 cases of ChD transmitted through ingestion of guava juice contaminated with Trypanosoma cruzi in an urban school setting. Patients received treatment with either benznidazole or nifurtimox as antiparasitic agents. Among the participants, 76 were aged 18 years or younger (mean age: 9.1 ± 3.1 years), and 27 were older than 18 years. All subjects underwent an initial clinical and laboratory assessment, which comprised parasitological examinations, electrocardiogram (EKG), Holter monitoring, and echocardiography. Follow-up evaluations, including clinical assessments, laboratory tests, and cardiac monitoring, were conducted every six months over an 18-year period.

Results

In the acute phase, 5 patients developed acute HF (4.85%), with ages ranging from 5 to 60 (38 ± 27) years. A 5-year-old boy developed documented ventricular tachycardia and died suddenly in the second week of evolution. Two cases had reduced left ventricular ejection fraction, one was moderately reduced, and two were preserved. All presented with pericardial effusion, one severe and four moderate. Sixty-eight [68 (66%)] patients presented ECG abnormalities, the most frequent being ST-segment and T-wave abnormalities (37 %). Arrhythmias were detected in 28 cases (27%); atrial tachycardia in 13 cases, inappropriate sinus tachycardia in 10 patients, atrial fibrillation in 4 cases and ventricular tachycardia in 4 cases.

All survivors were administered cardiovascular medications (angiotensin receptor blockers, beta-blockers, mineralocorticoid receptor antagonists, furosemide, and colchicine) and were fully recovered at 6 months. After 18 years of follow-up, no cases presented with HF or left ventricular systolic dysfunction.

Conclusion

This study highlights the importance of the largest urban, orally transmitted ChD outbreak, which exhibited characteristics that deviate from classic vectorial transmission. Despite high initial morbidity, the mortality rate was low due to early diagnosis and timely parasiticidal treatment. The 18-year outcome was excellent, with marked recovery of ventricular function and an absence of chronic heart failure or persistent systolic dysfunction.