Background: Clinical implications of online 3-dimensional optical frequency domain imaging (3D-OFDI)-guided stenting for bifurcation lesions have not been investigated in the randomized controlled trials. The purpose of this study was to determine whether online 3D-OFDI-guided stenting is superior to angiography-guided percutaneous coronary intervention (PCI) in terms of incomplete stent apposition at the bifurcation segment. Methods: The OPTIMUM trial (Online 3-Dimensional Optical Frequency Domain Imaging to Optimize Bifurcation Stenting Using UltiMaster Stent) was a randomized, multicenter clinical trial. Eligible patients had an angiographically significant stenosis in the bifurcation lesion treated with a provisional single stent strategy using the Ultimaster sirolimus eluting stent. Patients were randomly allocated to either online 3D-OFDI-guided or angiography-guided PCI. Patients randomized to 3D-OFDI guidance underwent online 3D-OFDI assessment after rewiring into the jailed side branch after stenting and proximal optimization technique, while in the angiography guidance arm, rewiring was performed using conventional fluoroscopic/angiographic guidance. The primary end point of this trial was the postprocedural average percentage of malapposed struts per lesion assessed by OFDI in the confluence zone of the main and side branches. Results: Between June 8, 2017 and September 26, 2018, 110 patients with 111 bifurcation lesions were randomized at 4 Japanese centers. Of these, 56 patients with 57 lesions were treated with 3D-OFDI-guided PCI, whereas 54 patients with 54 lesions were treated with angiography-guided PCI. In the 3D-OFDI guidance arm, the feasibility of online 3D-OFDI was 98.2%. The average percentage of incomplete stent apposition per lesion at bifurcation was lower in the 3D-OFDI guidance arm than that in the angiography guidance arm (19.5±15.8% versus 27.5±14.2%, P =0.008). The superiority of the 3D-OFDI guidance arm was also confirmed in the strut level analysis (odds ratio: 0.54 [95% CI, 0.36–0.81]; P =0.003). Conclusions: Online 3D-OFDI-guided bifurcation PCI was superior to angiography-guided bifurcation PCI in terms of acute incomplete stent apposition at bifurcation. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02972489.

Background: Little large-scale data is available about the long-term (beyond 3 years) clinical outcomes after fractional flow reserve (FFR)–based deferral of revascularization in clinical practice. We sought to assess the 5-year outcomes after deferral of revascularization based on FFR. Methods: The J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry) prospectively enrolled 1263 patients with 1447 lesions in whom revascularization was deferred based on FFR from 28 Japanese centers. The primary study end point was the cumulative 5-year incidence of target vessel failure (TVF), including cardiac death, target vessel–related myocardial infarction, and clinically driven target vessel revascularization. Results: Five-year follow-up was completed in 92.2% of patients. The 5-year TVF rate was 11.6% in deferred lesions, mainly driven by clinically driven target vessel revascularization (9.8%). Cardiac death and target vessel–related myocardial infarction were 1.9% and 0.95%, respectively. Cumulative 5-year incidence of TVF was similar between the FFR 0.75 to 0.80 and 0.81 to 0.85 groups even after adjustment for baseline characteristics (12.2% versus 13.0%, inverse probability–weighted hazard ratio, 0.86 [95% CI, 0.46–1.60]; P =0.63). Compared with the almost normal FFR (0.86–1.00) group, the significant (<0.75) and borderline (0.75–0.85) FFR groups showed a higher incidence of TVF at 5 years (29.9% versus 12.8% versus 8.6%, P <0.001). Independent predictors of the 5-year TVF were hemodialysis, FFR value, left main coronary artery lesion, prior percutaneous coronary intervention, and male sex. Conclusions: The 5-year TVF rate was 11.6% in deferred lesions, mainly driven by clinically driven target vessel revascularization. Notably, cardiac death and target vessel–related myocardial infarction rarely occurred during the follow-up. Our findings highlight the long-term safety of FFR-based deferral of revascularization in patients with chronic coronary syndrome. Registration: URL: https://www.umin.ac.jp/ctr ; Unique identifier: UMIN000014473.

Invasive functional coronary angiography (FCA), an angiography-derived physiological index of the functional significance of coronary obstruction, is a novel physiological assessment tool for coronary obstruction that does not require the utilization of a pressure wire. This technology enables operators to rapidly evaluate the functional relevance of coronary stenoses during and even after angiography while reducing the burden of cost and complication risks related to the pressure wire. FCA can be used for treatment decision-making for revascularization, strategy planning for percutaneous coronary intervention, and procedure optimization. Currently, various software-computing FCAs are available worldwide, with unique features in their computation algorithms and functions. With the emerging application of this novel technology in various clinical scenarios, the Japanese Association of Cardiovascular Intervention and Therapeutics task force was created to outline expert consensus on the clinical use of FCA. This consensus document advocates optimal clinical applications of FCA according to currently available evidence while summarizing the concept, history, limitations, and future perspectives of FCA along with globally available software. Graphical abstract Overview and proposed clinical applications of functional coronary angiography (FCA). The FCA was developed according to computed fluid dynamics (CFD), considering the pressure drop across the coronary stenosis. CFD analysis was performed with a three-dimensional coronary model derived from angiography, allowing the calculation of the physiological index without the use of a pressure wire. Another direction of development in FCA is using artificial intelligence throughout the entire process, enabling “hands-free” FFR simulation. The advantage of the FCA is that it eliminates the use of a pressure wire, resulting in reduced invasiveness, shorter procedure times, and reduced medical costs. However, FCA requires high-quality angiography for a clear visualization of the lesion. In addition, the current version of FCA requires several manual corrections; thus, its reproducibility is limited. Further data on clinical outcomes after the use of FCA, such as percutaneous coronary intervention (PCI) with FCA guidance, are warranted. The consensus group of the Japanese Association of Cardiovascular Intervention and Therapeutics proposed the application of FCA in various clinical scenarios considering the advantages of this technology. QFR, quantitative flow ratio; iFR, instantaneous wave-free ratio; CCS, chronic coronary syndrome; ACS, acute coronary syndrome; MVD, multivessel disease; AMI, acute myocardial infarction.

A second iteration of a sirolimus-eluting stent (SES) that has a biodegradable PLGA polymer coating with an electrografting base layer on a thin-strut (80 µm) cobalt-chromium platform (BuMA Supreme; SINOMED, Tianjin, China) has been developed. This first-in-man trial aimed to assess the efficacy and safety of the novel device. This randomised, multicentre, single-blinded, non-inferiority trial compared the BuMA Supreme SES versus a contemporary durable polymer zotarolimus-eluting stent (ZES) in terms of angiographic in-stent late lumen loss (LLL) at nine-month follow-up as the primary endpoint. A total of 170 patients were randomly allocated to treatment with either SES (n=83) or ZES (n=87). At nine-month angiographic follow-up, in-stent LLL was 0.29±0.33 mm in the SES group and 0.14±0.37 mm in the ZES group (pnon-inferiority=0.45). The in-stent percent diameter stenosis and the binary restenosis rate of the two treatment arms were similar (19.2±12.0% vs. 16.1±12.6%, p=0.09, and 3.3% vs. 4.4%, p=1.00, respectively). At 12-month clinical follow-up, there was no difference between treatment arms with regard to the device-oriented composite clinical endpoint (4.9% vs. 5.7%; p=0.72). The PIONEER trial did not meet its primary endpoint in terms of in-stent LLL at nine-month follow-up. However, this result did not translate into any increase in restenosis rate or impairment in 12-month clinical outcomes.