[Gallium-67 imaging in patients with myocarditis in childhood and youth]

Gallium-67 (Ga-67) myocardial imaging was performed in 19 patients (1 month to 21 years of age) with proven or suspected myocarditis. The anterior images, 48 hrs after the intravenous administration of 0.5-2.0 mCi Ga-67 citrate, were analysed using a computer. Regions of interest were set on the heart, lungs and background, excluding the sternum and vertebrae. The uptake of Ga-67 was evaluated quantitatively by the ratio of the average count of the heart to the average count of the lung (H/L). When the H/L value was higher than 130% the cardiac uptake of Ga-67 was designated positive. Histological examination was performed in 11 patients who underwent right endomyocardial biopsy. The patients were categorized according to their clinical findings. Group 1 consisted of 11 patients with clinical symptoms of dilated cardiomyopathy, six of whom had arrhythmias or elevated serum CPK-MB levels (group Ia) in the acute stage of the disease, and the remaining five had neither (group Ib). Group 2 consisted of eight patients with dysrhythmias but without heart failure. Four had elevated serum CPK-MB levels (group IIa), but the remaining four did not (group IIb). All patients in the group Ia had positive Ga-67 uptakes, and three patients in the group Ib had negative uptakes. The H/L values were significantly higher in the group Ia than in the group Ib (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)