Stepwise Assessment of Computational Coronary Physiology and Plaque Vulnerability

BACKGROUND: Incremental information on coronary physiology and plaque vulnerability may improve risk stratification beyond anatomy. Murray law-based quantitative flow ratio (μFR) and radial wall strain (RWS) are angiography-derived indices for assessing coronary physiology and plaque vulnerability, but their impact on revascularization decisions remains unclear. OBJECTIVES: The authors aimed to evaluate the impact of incremental availability of μFR and RWS on revascularization decisions. METHODS: A web-based survey was conducted, comprising 25 angiographically intermediate lesions. Data from μFR, RWS, and optical coherence tomography (OCT) were stepwisely available to participating cardiologists to make revascularization decisions (medical therapy alone or revascularization) for each lesion: Decision I was made based on angiography and clinical data, Decision II was made after μFR was disclosed, Decision III followed after RWS disclosure, and Decision IV followed after OCT disclosure. RESULTS: A total of 87 interventional cardiologists from 30 Chinese clinical centers provided 1,975 lesion-based decision sets. Following stepwise data disclosure, revascularization decisions remained unchanged in 1,013 (51.3%) decision sets. From Decision I to Decision II, 416 (21.1%) treatment recommendations changed, with 322 shifting from revascularization to medical therapy. From Decision II to Decision III, 315 (15.9%) recommendations changed, with 223 from medical therapy to revascularization. From Decision III to Decision IV, 564 (28.6%) recommendations changed, with 526 from medical therapy to revascularization. If decisions were strictly based on OCT-derived lipid-to-cap ratio, a validated quantification of plaque vulnerability, only 317 (16.1%) decisions would change from Decision III to Decision IV. CONCLUSIONS: Revascularization decisions for intermediate lesions changed significantly with sequential diagnostic data. Adding μFR to angiography decreased revascularization rates. Adding plaque vulnerability assessment significantly increased revascularization rates.