New compounds needed to improve cardiac functional mapping in heart disease care
The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. The norepinephrine transporter (NET) substrates [123I]-m-iodobenzylguanidine (MIBG) and [11C]-m-hydroxyephedrine (HED) are used as markers of cardiac sympathetic neurons and adrenergic tumors (pheochromocytoma, neuroblastoma). However, their rapid NET transport rates limit their ability to provide accurate measurements of cardiac nerve density. Therefore new compounds are desired.
Improved radiolabeled compounds for cardiac nuclear medicine
This invention relates to a series of compounds that are structurally related to MIBG, namely radiolabeled phenethylguanidines, which possess kinetic properties that may make them superior to MIBG for nuclear medicine applications. These compounds can be radiolabeled with several radioisotopes, including radio-halogens such as iodine-123 (123I) for single photon imaging (SPECT imaging) studies, iodine-131 (131I) for radiotherapy of adrenergic tumors, and carbon-11 (11C) or fluorine-18 (18F) for positron emission tomography imaging (PET imaging) studies.
Applications and Advantages
- Radiotracers for imaging cardiac sympathetic neurons
- This invention provides improved kinetics for quantifying cardiac nerve density.
- This invention provides compounds that can be radiolabeled with several different radioisotopes to be applied in different imaging systems.