Studies of the Relationship between Decreased Myocardial ¹²³I-Metaiodobenzylguanidine (MIBG) Uptake and Clinical Examination Findings in Patients with Non-Insulin Dependent Diabetes Mellitus

Abstract

Myocardial distribution of¹²³I-MIBG was examined in 43 NIDDM patients (33 men, 10 women, age58.9±15.9years) using single-photon emission tomography. According to the defect pattern of¹²³I-MIBG imaging, the patients were divided into three groups. The study groups consisted of group N with normal¹²³I-MIBG uptake (n=18), group I with normal¹²³I-MIBG uptake at15min and a perfusion defect of the inferior wall at180min after injection (n=15), and group II with a clear perfusion defect to the inferior wall at both 15min and 180min after injection (n=10). Diabetic duration of group I and II was significantly longer than group N (N 4.6 years vs. I 10.4 years, II 15.0 years) and fasting plasma glucose and HbAic of I and II groups tended to be higher than for group N (HbAic N 6.5%vs. I 7.5%, II 7.6%). Patients with diabetic retinopathy, nephropathy or neuropathy were more frequent in group II than in either group N or group I. Six of ten patients in group II had retinopathy, and three of these, had B stage retinopathy, but groups N and I included no retinopathy patients. Patients with diabetic nephropathy were seven of ten in group II, but no patients in group N had nephropathy. Nerve conduction velocity in group II was significantly slower than in group N (N52.6m/sec vs. II 41.5m/sec), CV_{R_R}was remarkably smaller than in group N (N 3.18% vs. II 1.71%) and washout rate of¹²³I-MIBG from 15min to 180 min after injection was significantly accelerated in group II (N 10.4% vs. II 24.9%). Every group included 20-30% of patients with hypertension and cardiomegaly. In regards to blood pressure and cardiothoracic ratio no significant differences were found among the three groups. In group II, two patients had atrial fibrillation.