Prognostic Implication of Computational Angiography-Derived Fractional Flow Reserve in Patients With Nonobstructive Coronary Artery Disease

Background Risk stratification of patients with symptomatic nonobstructive coronary artery disease remains uncertain. Our study assessed the clinical value of single-vessel, multivessel, and 3-vessel computational angiography-derived fractional flow reserve (caFFR) measurement in patients with nonobstructive coronary artery disease.Methods and Results We enrolled patients with <= 50% stenosis with a caFFR value >= 0.8 in all 3 coronary arteries on coronary angiography. The sum of caFFR values in the 3 vessels was computed for each patient. Patient stratification was based on the median value of the following criteria: single-vessel analysis, multivessel analysis, and 3-vessel analysis. The primary end point of this study was major adverse cardiac events at 5 years, defined as a composite of cardiac death, myocardial infarction, and ischemia-driven revascularization. A total of 490 patients were included. The 5-year major adverse cardiac event rates in single-vessel analysis were statistically insignificant between low- and high-caFFR groups (left anterior descending artery [P=0.163]; left circumflex artery [P=0.797]; right coronary artery [P=0.127]). In multivessel analysis, patients in the multiple-vessel low-caFFR group (with 2-3 vessels lower than median value of all coronary arteries) showed an increased risk of 5-year major adverse cardiac events compared with patients in the single-vessel low-caFFR group (0-1 vessel) (hazard ratio [HR], 2.648 [95% CI, 1.141-6.145]; P=0.023). In 3-vessel analysis, patients in the low 3-vessel caFFR group demonstrated a greater 5-year major adverse cardiac event risk than the high 3-vessel caFFR group (HR, 2.43 [95% CI, 1.087-5.433]; P=0.031).Conclusions We demonstrated that both multiple-vessel and 3-vessel caFFR measurements serve as valuable prognostic indicators for risk assessment in patients with nonobstructive coronary artery disease.