Clinical Outcomes of Deferred Lesions by IVUS Versus FFR-Guided Treatment Decision

BACKGROUND: There are limited data regarding the safety of deferral of percutaneous coronary intervention based on intravascular ultrasound (IVUS) findings. The current study sought to compare the prognosis between deferred lesions based on IVUS and fractional flow reserve (FFR)-guided treatment decision. METHODS: This study is a post hoc analysis of the FLAVOUR randomized trial (Fractional Flow Reserve and Intravascular Ultrasound for Clinical Outcomes in Patients With Intermediate Stenosis) that compared 2-year clinical outcomes between IVUS-and FFR-guided treatment decision on intermediate coronary artery lesions using predefined criteria. In both IVUS and FFR groups, vessels were classified into deferred or revascularized vessels, and patients were classified as those with or without deferred lesions. Vessel-oriented composite outcomes (cardiac death, target vessel myocardial infarction, or target vessel revascularization) in deferred vessels and patient-oriented composite outcomes (death, myocardial infarction, or any revascularization) in patients with deferred lesions were compared between the IVUS and FFR groups. RESULTS: A total of 1682 patients and 1820 vessels were analyzed, of which 922 patients and 989 vessels were deferred. At 2 years, there was no difference in the cumulative incidence of vessel-oriented composite outcomes in deferred vessels between IVUS (n=375) and FFR (n=614) groups (3.8% versus 4.1%; hazard ratio, 0.91 [95% CI, 0.47-1.75]; P=0.77). The risk of vessel-oriented composite outcomes was comparable between deferred and revascularized vessels following treatment decision by IVUS (3.8% versus 3.5%; hazard ratio, 1.09 [95% CI, 0.54-2.19]; P=0.81) and FFR (4.1% versus 3.6%; hazard ratio, 1.14 [95% CI, 0.56-2.32]; P=0.72). In comparison of patient-oriented composite outcomes in patients with deferred lesions, there was no significant difference between the IVUS (n=357) and FFR (n=565) groups (6.2% versus 5.9%; hazard ratio, 1.05 [95% CI, 0.61-1.80]; P=0.86). CONCLUSIONS: In patients with intermediate coronary artery stenosis, deferral of percutaneous coronary intervention based on IVUS-guided treatment decision showed comparable risk of clinical events with FFR-guided treatment decision. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02673424.