Radionuclide (MUGA) studies of left ventricular functional abnormalities in asymptomatic patients with sickle cell anemia.

Radionuclide ventriculography was performed on 10 normal subjects and 39 patients with sickle cell anemia (10 homozygous and 29 heterozygous sicklers) at rest and after exercise. Their left ventricular (LV) function was assessed in both these situations. The results were then compared within the subgroups. The reduction in ejection fraction (EF) response (47.5 +/- 7 at rest and 46.4 +/- 8 at exercise in homozygous patients, and 52.4 +/- 8 at rest and 54.3 +/- 8 at exercise in heterozygous patients) was significant in both the homozygous and the heterozygous groups but more so in the former group. The diastolic filling was also significantly impaired in the homozygous group (PER 2.64 +/- 0.74, PFR 2.13 +/- 0.42 and PFR/HR 0.014 +/- 0.001). The study statistically demonstrates, that LV filling patterns are altered in the sickle cell patients, even in the absence of clinical symptoms relating to LV dysfunction. This fact may prove to be a marker of sickle cell heart disease. Frequent and significant sickling is probably the cause of more pronounced LV functional abnormalities in homozygous sicklers.