[Assessment of ischemic damage of the cardiac sympathetic nerve function by semiquantitative analysis of 123I-MIBG (metaiodobenzylguanidine)-SPECT--comparison with 201Tl-Cl-SPECT].

Recently 123I-MIBG scintigraphy has been developed for evaluating the function of cardiac sympathetic nerve. To assess its ischemic damage, dual SPECT with 123I-MIBG and 201Tl-Cl were performed in 24 patients with ischemic heart disease and 8 normal subjects. In order to evaluate extent and severity of ischemic damage, Tl and MIBG abnormal scores were calculated by Bull's eye map. In patients with Non-Q wave myocardial infarction (NQMI), MIBG abnormal scores were significantly higher than Tl scores (p less than 0.01). In the regions where regional wall motion showed hypokinesis, MIBG abnormalities were detected in all cases whereas Tl abnormalities existed only in 42%. MIBG abnormality score in NQMI group with negative T wave and wall motion asynergy was significantly higher than that of NQMI group without T wave abnormality and asynergy (p less than 0.01). Ischemic damage of cardiac sympathetic nerve seemed to contribute to negative T wave and stunned myocardium. 123I-MIBG scintigraphy was thought to be a sensitive and useful method for clinical evaluation of ischemic heart disease.