Coronary Inflammation by Computed Tomography Pericoronary Fat Attenuation in MINOCA and Tako‐Tsubo Syndrome

Abstract

Background The pericoronary fat attenuation index (pFAI) has emerged as a marker of coronary inflammation, which is measurable from standard coronary computed tomography angiography (CCTA). It compares well with gold‐standard methods for the assessment of coronary inflammation and can predict future cardiovascular events. pFAI could prove invaluable to differentiate an inflammatory from a noninflammatory coronary artery status, helping unravel the mechanisms subtending an event classified as myocardial infarction with nonobstructive coronary arteries (MINOCA) or Tako‐Tsubo syndrome (TTS). Methods and Results Patients admitted with MINOCA and TTS between 2011 and 2018, who had both CCTA and cardiac magnetic resonance during or shortly after the acute phase, were selected and pFAI measured in their CCTA; pFAI was also measured in control subjects who had CCTA for atypical chest pain workup, no obstructive coronary artery disease found in their CCTA, and no cardiac events at 2‐year follow‐up. In the n=106 MINOCA/TTS patients, mean pFAI was −68.37±8.29 versus −78.03±6.20 in the n=106 controls (P<0.0001), and the difference was confirmed also when comparing mean pFAI in each coronary artery between MINOCA/TTS and controls (P<0.0001). Nonobstructive coronary plaques at CCTA, high‐risk plaques in particular, were more frequently found (P<0.01) in the MINOCA/TTS group compared with controls. Conclusions In MINOCA and TTS patients, CCTA is not only able to detect angiographically invisible atherosclerotic plaques, but its diagnostic yield can be expanded using the simple measurement of pFAI to characterize pericoronary fat tissue; in MINOCA/TTS mean pFAI demonstrates higher values compared with controls, a finding that has been associated with coronary artery inflammation.