11C-meta-hydroxyephedrine: a promising PET radiopharmaceutical for imaging the sympathetic nervous system
Stefano Boschi1, Filippo Lodi, Laura Boschi
1From the *Department of Nuclear Medicine, Sant' Orsola Hospital, University of Bologna School of Medicine, Italy; †Department of Radiology, University of Southern California School of Medicine, Los Angeles, CA; ‡Department of Nuclear Medicine, Santa Maria della Misericordia Hospital, Rovigo, Italy.
Abstract:
Dysfunction of the sympathetic nervous system underlies many cardiac diseases and can be assessed by molecular imaging using SPECT tracers as I-metaiodobenzylguanidine (I-MIBG). The norepinephrine analog C-meta-hydroxyephedrine (HED) has been used with PET to map the regional distribution of cardiac sympathetic neurons. Hydroxyephedrine is rapidly transported into sympathetic neurons by the norepinephrine transporter and stored in vesicles. This review describes the mechanism of action, radiosynthesis, and application of HED in the assessment of the cardiac sympathetic nervous system in heart failure, myocardial infarction, and arrhythmias. Noncardiac applications of HED in the clinical setting of sympathetic nervous system tumors and other emerging research applications are described.
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