Radionuclide imaging for the detection of inflammation in vulnerable plaques

Area of Science:

• Cardiovascular imaging
• Nuclear medicine
• Atherosclerosis research

Background:

• Traditional imaging focuses on luminal stenosis, not plaque vulnerability.
• Vulnerable plaques, characterized by inflammation, cause most life-threatening cardiovascular events.
• There is a critical need for imaging techniques to quantify inflammation in atherosclerotic lesions.

Purpose of the Study:

• To review the potential of nuclear imaging techniques for assessing inflammation in atherosclerotic plaques.
• To discuss the development of tracers for key inflammatory markers.
• To highlight challenges in imaging coronary artery inflammation.

Main Methods:

• Review of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging.
• Discussion of tracer development for macrophage recruitment, foam cell generation, matrix metalloproteinase production, apoptosis, and metabolism.
• Evaluation of imaging in carotid and peripheral circulation.

Main Results:

• PET and SPECT imaging show promise for detecting inflammation in peripheral and carotid atherosclerosis.
• Various tracer compounds targeting inflammatory processes have been developed and tested.
• Successful identification of inflamed lesions in the coronary circulation is currently elusive.

Conclusions:

• Nuclear imaging offers a promising avenue for visualizing and quantifying inflammation in vulnerable atherosclerotic plaques.
• Tracer development has advanced significantly for assessing key inflammatory pathways.
• Challenges related to plaque size, motion, and tracer specificity hinder coronary imaging, necessitating further research.