[Frequency of electrocardiographic alterations in apparently healthy persons with indirect hemagglutination reaction positive for toxoplasmosis].

An indirect hemagglutination test (IHAT) for toxoplasmosis and electrocardiogram (EKG) were performed to 11,161 apparently healthy inhabitants with negative IHAT for Chagas' disease, from 259 rural and periurban localities sited in the first seven regions of Chile (geographic area of distribution of Chagas' disease in the country). The age of the 11,161 examined people ranged between 5 and 94 years, being 4,518 males and 6,643 females. The IHAT for toxoplasmosis was considered positive with titers > or = 1:16. This test resulted positive in 3,519 (31.1%) persons (30.8% in males and 32.0% in females). Positivity of the IHAT increased from 21.2%, in the youngest group (< 10 years) up to 46.9% in the oldest group (> or = 60 years). Different types of EKG alterations were observed in 10.9% of the IHAT positive individuals and in 7.9% of the IHAT negative ones. In both groups the percentages of altered EKG increased parallel with age. The overall difference of percentages of altered EKG in IHAT positive and IHAT negative persons has a statistical significance with p < 0.001. This study suggest the convenience to consider toxoplasmosis as a cause of chronic myocardiopathy in epidemiological studies on Chagas' disease, because a possible Toxoplasma gondii infection may contribute to overincrease the magnitude of the impact of Trypanosoma cruzi in the generation of the quoted myocardiopathy.