Right coronary artery pericoronary fat attenuation index as a future predictor for acute coronary events in nonobstructive coronary artery disease - a prospective single centre study

AIM: Evaluation of pericoronary adipose tissue changes induced by inflammation by non- invasive techniques is challenging. PURPOSE: To find the association between pericoronary adipose tissue attenuation (FAI) changes and future acute coronary events in nonobstructive coronary artery disease. MATERIALS AND METHODS: Ours was a single-centre, prospective observational study on patients with atypical chest pain who underwent coronary computed tomography angiog- raphy (CCTA). In patients with CADRADS 1 to 3 nonobstructive coronary artery disease (CAD), pericoronary FAI was measured around the proximal right coronary artery (RCA) and coronary artery segment with plaque using semi-automated postprocessing software. Patients were followed up for development of acute coronary events (ACE). Kaplan-Meier curves were used to see event-free survival rates. RESULTS: Of 120 patients with a mean follow-up period of 67 months, 21 patients developed acute coronary events. RCA-FAI and lesion FAI of patients with ACE were significantly higher as compared to patients without events. ROC curve analysis showed RCA-FAI as the best predictor of ACE at a cut-off point of >-77.3 Hounsfield unit (HU) (with an AUC of 0.915) with high sensitivity (95.24%), specificity (83.84%), and negative predictive value (98.80%). On multi- variate analysis, RCA-FAI, diabetes mellitus, and stenosis >= 50% were independent risk factors of ACE with hazard ratios of 1.335 (1.173-1.518), 4.950 (1.716-14.278), and 7.446 (2.257-24.566), respectively. CONCLUSION: RCA FAI can predict ACE in nonobstructive coronary artery disease patients. Detection of high RCA FAI of >-77.3 HU on CCTA can help to identify high-risk patients who need regular follow-up and early initiation of interventions.(c) 2024 The Royal College of Radiologists. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.