I‐123 metaiodobenzylguanidine—thallium‐201 mismatch following myocardial infarction

Abstract

Summary: Experimental data show that myocardial infarction (MI) results in regional depletion of myocardial cathecholamines more extensively than necrosis. To investigate the extent ofadrenergic deneivation post MI in humans, we examined 16 palients. 59 k I2 yeas old, with recent (7-I2 days) MI. Resting thallium-201 (201TI) single photon emission computerized tomography (SPECT) imaging was performed to assess necrosis: tiietaiodobenzylguanidine 1123 (MIBG) SPECT was used to evaluate adrenergic denervation. ""TI and MIBG defects were evaluated quantitatively using polar maps, and differences in defects were expressed as percent of total polar map. In all paticnts, MIBG defect was larger than '"'TI defect, and difference ranged from 19 to 61 % (39.5 t-13.2%). Thrombolysis and age >60 did not influence the difference. Anterior MI showed larger differences (44 t-13 vs. 32 t-I I %, p < 0.05); patients with ischemic electrocardiographic (ECG) changes in leads without abnormal Q waves had larger differences (45 k 9 vs. 33 14%. p<O.OS). It was concluded that (a) patients with recent MI present denervation larger than 201Tl perfision defect, and (b) patients with anterior MI and ischemic ECG changes present a larger area of denervation.

Evaluation of Probable or Possible Dementia with Lewy Bodies Using 123I-IMP Brain Perfusion SPECT, 123I-MIBG, and 99mTc-MIBI Myocardial SPECT

“…MIBG-MIBI mismatch often can be observed in acute myocardial infarction and transient myocardial ischemia attacks such as unstable angina pectoris or vasospastic angina pectoris (38,39). In our patients, there was no history or sign of cardiac disease or ECG abnormalities.…”

123I-MIBG SPECT for Evaluation of Patients with Heart Failure

“…Initially, semiquantitative scoring from a visual analysis, analogous to that used in MPI, was performed, as noted earlier for studies of patients after MI (27,28). When quantitative bull's-eye mapping for MPI SPECT became readily available, it was also applied to 123 I-MIBG SPECT analysis (23,(50)(51)(52). However, because the quantitative programs were usually adapted from those developed for MPI SPECT, they did not take into account the unique physical properties of MIBG iodinated with 123 I, which affects image quality.…”

Imaging of myocardial autonomic innervation in patients with congestive heart failure: Methods and clinical implications

“…After heart transplantation, partial sympathetic reinnervation was demonstrated using 128I-MIBG imaging [132,133]. Myocardial ischemia and infarction produce regional efferent sympathetic denervation, which can be visualized by MIBG scintigraphy and may influence arrhythmias [134][135][136][137][138][139][140][141][142][143]. Abnormalities of sympathetic innervation, demonstrated by MIBG imaging, are frequent in patients with ventricular arrhythmias without apparent heart disease [144][145][146][147], in patients found with the congenital long-QT syndrome [148], and in those with arrhythmogenic right ventricular disease [149,150].…”