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

Abstract

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 angiography (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 multivariate 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.