부산대학교 도서관

It is crucial to predict drug effectiveness in chronic disease, such as dilated cardiomyopathy (DCM), in which the left ventricular (LV) function might be improved by β-blocker therapy. As the functional improvement effected by β-blocker therapy takes more than 2 months, we investigated whether iodine-123 metaiodobenzylguanidine ([sup 123]I-MIBG) imaging could be used to predict drug effectiveness. We studied 13 patients (11 men and two women; mean age, 43±13 years) with DCM and seven normal subjects (six men and one woman; mean age, 48±16 years). We obtained myocardial single-photon emission tomography (SPET) images 15 min and 4 h after administration of [sup 123]I-MIBG (111 MBq). Studies were performed in the patients with DCM before and 1 and 3 months after the administration of metoprolol and in the normal subjects. We calculated the regional [sup 123]I-MIBG washout rate (r-WR) in the SPET image, and the global [sup 123]I-MIBG washout rate (gWR) and heart-mediastinum activity ratio (H/M) using the anterior planar image. We classified patients into those showing a ≥5% increase in LV ejection fraction (LVEF) at 3 months compared with LVEF values before the treatment (group I, n=7) and those showing a <5% increase in LVEF (group II, n=6). In group I, the r-WR values at pretreatment and at 1 month and 3 months of treatment, respectively, were 36%±19%, 29%±14% and 25%±13% in the anterior segment, 39%±17%, 33%± 17% and 28%±17% in the lateral segment, 36%± 16%, 31%±14% and 22%±12% in the septal segment and 40%±11%, 37%±19% and 31%±18% in the inferior segment; the g-WR was 45%±11%, 43%±10% and 34%±9%, respectively (P<0.05, P<0.01 vs pretreatment). In group II, there were no significant changes in regional or global parameters during the 3month period. In normal subjects, the r-WR values in each of the anterior, lateral, septal and... [ABSTRACT FROM AUTHOR]