Radionuclide evaluation of left-ventricular function in chronic Chagas' cardiomyopathy

Left-ventricular ejection fraction (LVEF) and abnormalities of regional wall motion (WMA) were studied by means of radionuclide ventriculography in 41 patients prospectively diagnosed as having chronic Chagas' disease. Thirteen patients were asymptomatic (ASY), 16 were arrhythmic (ARR), and 12 had congestive heart failure (CHF). Mean LVEF was normal in ASY (0.64 +/- 0.06) but markedly depressed in CHF (0.28 +/- 0.08). Regional WMAs were minimal in ASY and their severity increased in ARR. Most CHFs (75%) had diffuse hypokinesia of the left ventricle. The region most frequently affected was the infero-apical (63%). Seven patients had a distinct apical aneurysm. Correlation between radionuclide and contrast ventriculography data was good in 17 patients. For LVEF, r = 0.90. For WMA there was agreement between the two techniques in 77% of 65 segments compared. Best agreement occurred with infero-apical lesions (88%), and worst with septal (69%). Selective coronary arteriography showed normal arteries in all patients. Therefore, chronic Chagas' heart disease joins ischemic heart disease as a cause of regional WMA.