Feasibility of coronary angiogram-derived vessel fractional flow reserve in the setting of standard of care percutaneous coronary intervention and its correlation with invasive FFR.

BACKGROUND: Vessel Fractional Flow Reserve (vFFR), a new angiography-derived method for the functional assessment of coronaries, was recently shown to have good correlation with invasive wire-derived FFR, when vFFR-specific image acquisition requirements were followed. We sought to investigate the feasibility of vFFR analysis and its correlation with FFR in the situation where angiography is completed in routine fashion, without intention for virtual analysis. METHODS: Utilizing an anonymized database maintained at our Cardiovascular Imaging Core Laboratory, we included angiographic images from patients that underwent pre- and post-PCI FFR. CAAS Workstation 8.1 software (Pie Medical Imaging) was used for vFFR evaluation. RESULTS: Out of 624 angiograms (312 pre-PCI and 312 post-PCI), vFFR was successfully analyzed in 219 (35.1%) (115 pre-PCI and 104 post-PCI). Reasons for vFFR analysis failure were: <2 angiographic projections (42.5%), table movement while acquisition (25.7%) and resolution incompatibility (15%). From 115 patients with analyzable pre-PCI vFFR, 74 (64.3%) showed agreement with the respective FFR results in terms of positive (≤0.80) vs negative (>0.80) FFR. Pearson's correlation coefficient between them was 0.449 (p < 0.0001). From 104 lesions with analyzable post-PCI vFFR, 94 had availability of FFR, 74 (78.7%) of which showed agreement between the vFFR and FFR. Pearson's correlation between the values was 0.115 (p = 0.2703). CONCLUSION: vFFR could be analyzed in about one-third of previously completed angiographies and a weak correlation was seen between vFFR and FFR. Our results show the importance of following the pre-specified requirements for vFFR analysis. Further studies are needed to validate the software in different settings.

Vascular response and healing profile of everolimus-eluting bioresorbable vascular scaffolds for percutaneous treatment of chronic total coronary occlusions: A one-year optical coherence tomography analysis from the GHOST-CTO registry.

BACKGROUND: Bioresorbable vascular scaffolds (BVS) have been heralded with potential benefits that are especially desired in long lesions, including chronic total occlusions (CTOs). Procedural feasibility and mid-term outcomes of BVS in CTOs have been reported. However, there is still a paucity of data regarding the vascular and healing response to BVS in CTOs evaluated by optical coherence tomography (OCT). METHODS: This study included prospectively 21 patients who had a CTO lesion treated with a BVS. Angiography and OCT scan were recorded at either post-implantation and 1-year follow-up. Quantitative coronary angiography and OCT analyses were performed by an independent core laboratory. RESULTS: The angiographic analysis showed a significant increase in the percentage of in-segment diameter stenosis at 1year (11.89±9.5% vs. 21.84±11.7%; p=0.002). The OCT analysis showed a trend (p=0.07) towards increased mean scaffold area and significant reductions in mean lumen diameter (3.1±0.36mm vs. 2.85±0.47mm; p=0.0046), mean lumen area (7.8±1.73mm2 vs. 6.76±2mm2; p=0.0082) and minimal lumen area (5.26±1.86mm2 vs. 3.56±1.52mm2; p<0.0001). Malapposition area and volume decreased from 0.26±0.17mm2 to 0.08±0.1mm2 (p=0.0003) and from 14.17±12.92mm3 to 3.99±4.46mm3 (p=0.0014), respectively. The rate of uncovered or malapposed struts, measured at the frame level, was 5.29±6.48% at 1year. CONCLUSIONS: In a small series of CTO patients treated with BVS implantation, OCT outcomes at 1year displayed an overall favorable vascular response and healing profile.