Trypanosoma cruzi Antibody Titers Predict Risk for Chagas Cardiomyopathy and Death

The protozoan parasite Trypanosoma cruzi, the etiologic agent of Chagas disease, is the most common cause of infectious cardiomyopathy worldwide. Still, the natural history of Chagas disease can be difficult to study: Most T. cruzi–seropositive individuals never experience cardiac damage, any damage that does occur may take decades to develop, and cardiomyopathy includes electrocardiogram changes nonspecific to Chagas disease (even in seropositive persons). Nunes and colleagues analyzed 10-year follow-up in 499 T. cruzi–seropositive blood donors (mean age, 49) from two centers in Brazil matched with 488 seronegative controls. New-onset cardiomyopathy was defined as ejection fraction <50%, QRS duration ≥120 milliseconds, or both.

Incidence of…