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.