CLINICAL USEFULNESS OF I-123 METAIODOBENZYLGUANIDINE MYOCARDIAL SCINTIGRAPHY IN DIABETIC-PATIENTS WITH CARDIAC SYMPATHETIC-NERVE DYSFUNCTION

To assess the clinical utility of I-123-metaiodobenzylguanidine (MIBG) scintigraphy in evaluating cardiac sympathetic nerve disturbance in d iabetic patients, we performed MIBG scintigraphy in 18 diabetic patien ts and 11 normal controls. Diabetic patients with symptomatic neuropat hy (DM2) had a significantly lower heart to mediastinum uptake ratio t han did those without neuropathy or normal controls in initial and del ayed images (initial image, 1.90+/-0.27 vs 2.32+/-0.38, 2.41+/-0.40, p <0.01; delayed image, 1.80+/-0.31 vs 2.48+/-0.35; 2.56+/-0.28, p<001, respectively). Defect score, assessed visually, were higher in DM2 pat ients than in patients in the other two groups (initial image, 7+/-2.6 vs 1.5+/-1.9, 0.7+/-0.9; delayed image 10.6+/-3.3 vs 4.0+/-2.5, 1.7+/ -1.6 p<0.01, respectively). The maximum washout rate in DM2 patients w as also higher than those in patients in the other two groups. The fin dings of these indices obtained from MIBG scintigraphy coincided with the % low-frequency power extracted from heart rate fluctuations using a power spectral analysis and the results of the Schellong test, whic h were used to evaluate sympathetic function. These results suggest th at MIBG scintigraphy may be useful for evaluating cardiac sympathetic nerve disturbance in patients with diabetes.