[Clinical usefulness of 123I-MIBG myocardial SPECT in patients with adriamycin-induced cardiomyopathy].

In 29 patients who had been administrated adriamycin (ADR) for the treatment of hematopoietic malignancies, myocardial SPECT was performed 20 minutes and 4 hours after an intravenous dose of 123I-metaiodobenzylguanidine (MIBG). Findings of the myocardial SPECT were compared with the total dose of ADR, ejection fraction (EF) and left ventricular wall motion, as assessed by ultrasound echocardiography. The mean total dose of ADR was 329.3 mg/m2 (range, 150-550 mg/m2). 1) Although the cardiac function was normal, the washout rate (WR) of MIBG was high in 75% of the patients whose MIBG myocardial SPECT showed abnormality on ADR, suggesting the presence of adrenergic nerve disorder. 2) The total dose of ADR was significantly correlated with WR of MIBG (p < 0.001). Consequently, WR of MIBG may be an index which reflects adrenergic nerve disorder in the myocardium earlier than EF. 3) It was suggested that adrenergic nerve disorder was involved in pathogenesis of myocardial complications associated with ADR administration. In summary, MIBG myocardial SPECT could be a useful test for determining a dosage regimen of ADR therapy of individual patients.