Risk stratification in coronary artery disease using NH3-PET myocardial flow reserve and CAD-RADS on coronary CT angiography

Abstract

Myocardial flow reserve (MFR) derived from 13N-ammonia positron emission tomography (NH3-PET) can predict the prognosis of patients with various heart diseases. Coronary computed tomography angiography (CCTA) is a non-invasive investigation for ischemic heart disease. The coronary artery disease reporting and data system (CAD-RADS) was established to standardize and facilitate the reporting of CCTA data regarding CAD. This study aimed to investigate the prognostic value of CAD-RADS and MFR. A total of 133 patients who underwent NH3-PET and CCTA within 3 months were enrolled. Patients were divided into groups with CAD-RADS 0–2 and\u2009≥\u20093 and into groups with MFR\u2009≥\u20092.0 and\u2009<\u20092.0. The endpoint was major adverse cardiac events (MACE) comprising all-cause death, acute coronary syndrome, hospitalization due to heart failure, and cerebrovascular disease. The ability of CAD-RADS and MFR to predict MACE was analyzed using Kaplan–Meier analysis. There was no significant difference in MFR between patients with CAD-RADS 0–2 and\u2009≥\u20093 (2.3\u2009±\u20090.9 vs. 2.2\u2009±\u20090.7, p\u2009=\u20090.50). The MACE rate for patients with CAD-RADS 0–2 and\u2009≥\u20093 was equivalent (log-rank test, p\u2009=\u20090.64). Patients with MFR\u2009<\u20092.0 had a significantly higher MACE rate than those with MFR\u2009≥\u20092.0 (p\u2009=\u20090.017). In patients with CAD-RADS\u2009≥\u20093, patients with MFR\u2009<\u20092.0 had a significantly higher MACE rate than those with MFR\u2009≥\u20092.0 (p\u2009=\u20090.034). CAD-RADS did not contribute to MACE prediction. Conversely, MFR was useful in predicting MACE, allowing for further risk stratification in addition to CAD-RADS.