A highly suspected case of chronic Chagas' heart disease diagnosed in Japan

A 50-year-old South American Indian woman, a native of Brazil and now a resident of Shiga Prefecture, was admitted to our hospital because of dyspnea on exertion. We initially suspected dilated cardiomyopathy due to an enlarged and diffusely hypokinetic left ventricle (LV) on echocardiogram. Coronary arteriograms were normal, and histological examination of right ventricular endomyocardial biopsy specimens showed findings compatible with chronic myocarditis. Magnetic resonance imaging revealed localized thinning and a small apical aneurysm at the LV. Since she had previously lived in a high-risk region for Chagas' disease, two immunological examinations for Trypanosoma cruzi were performed. The results of both tests were compatible with the disease. Recently, an increasing number of patients with Chagas' disease have been found in the United States among immigrants from South American countries, and the risk of transmission of the disease through contaminated blood transfusion is becoming a national problem. We report this case with reference to the present state of the problem in the United States and the potential problems it presents in Japan because of the marked increase in the number of immigrants from the affected area.