PCAT Attenuation Index: Explanation and Clinical Context PCAT Attenuation Index measures the mean CT attenuation of pericoronary adipose tissue surrounding coronary arteries in Hounsfield Units (HU). It serves as a non-invasive biomarker of coronary inflammation, with higher (less negative) values reflecting greater inflammatory activity in the vessel wall.
It is derived from coronary CT angiography by averaging the attenuation values of adipose tissue within a radial distance equal to the vessel diameter around the coronary artery.
Clinically, elevated PCAT attenuation has been shown to correlate with plaque vulnerability and adverse cardiovascular outcomes, providing additive risk stratification beyond traditional risk factors.
This tool enables clinicians and researchers to quantify coronary inflammation and potentially identify patients at higher risk for cardiovascular events.
Reference:
Antonopoulos AS, et al. Detecting human coronary inflammation by imaging perivascular fat. JACC Cardiovasc Imaging. 2017;10:1500-1510. doi:10.1016/j.jcmg.2017.05.021