Vessel fractional flow reserve (vFFR) for the assessment of stenosis severity: the FAST II study.

BACKGROUND: Fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) is superior to angiography-guided PCI. The clinical uptake of FFR has been limited, however, by the need to advance a wire in the coronary artery, the additional time required and the need for hyperaemic agents which can cause patient discomfort. FFR derived from routine coronary angiography eliminates these issues. AIMS: The aim of this study was to assess the diagnostic performance and accuracy of three-dimensional quantitative coronary angiography (3D-QCA)-based vessel FFR (vFFR) compared to pressure wire-based FFR (≤0.80). METHODS: The FAST II (Fast Assessment of STenosis severity) study was a prospective observational multicentre study designed to evaluate the diagnostic accuracy of vFFR compared to the reference standard (pressure wire-based FFR ≤0.80). A total of 334 patients from six centres were enrolled. Both site-determined and blinded independent core lab vFFR measurements were compared to FFR. RESULTS: The core lab vFFR was 0.83±0.09 and pressure wire-based FFR 0.83±0.08. A good correlation was found between core lab vFFR and pressure wire-based FFR (R=0.74; p<0.001; mean bias 0.0029±0.0642). vFFR had an excellent diagnostic accuracy in identifying lesions with an invasive wire-based FFR ≤0.80 (area under the curve [AUC] 0.93; 95% confidence interval [CI]: 0.90-0.96; p<0.001). Positive predictive value, negative predictive value, diagnostic accuracy, sensitivity and specificity of vFFR were 90%, 90%, 90%, 81% and 95%, respectively. CONCLUSIONS: 3D-QCA-based vFFR has excellent diagnostic performance to detect FFR ≤0.80. The study was registered on clinicaltrials.gov under identifier NCT03791320.

Correlation between 3D-QCA based FFR and quantitative lumen assessment by IVUS for left main coronary artery stenoses.

OBJECTIVES: We aimed to evaluate the feasibility of using three dimensional-quantitative coronary angiography (3D-QCA) based fractional flow reserve (FFR) (vessel fractional flow reserve [vFFR], CAAS8.1, Pie Medical Imaging) and to correlate vFFR values with intravascular ultrasound (IVUS) for the evaluation of intermediate left main coronary artery (LMCA) stenosis. BACKGROUND: 3D-QCA derived FFR indices have been recently developed for less invasive functional lesion assessment. However, LMCA lesions were vastly under-represented in first validation studies. METHODS: This observational single-center cohort study enrolled consecutive patients with stable angina, unstable angina, or non-ST-segment elevation myocardial infarction and nonostial, intermediate grade LMCA stenoses who underwent IVUS evaluation. vFFR was computed based on two angiograms with optimal LMCA stenosis projection and correlated with IVUS-derived minimal lumen area (MLA). RESULTS: A total of 256 patients with intermediate grade LMCA stenosis evaluated with IVUS were screened for eligibility; 147 patients met the clinical inclusion criteria and had a complete IVUS LMCA footage available, of them, 63 patients (63 lesions) underwent 3D-QCA and vFFR analyses. The main reason for screening failure was insufficient quality of the angiogram (51 patients,60.7%). Mean age was 65 ± 11 years, 75% were male. Overall, mean MLA within LMCA was 8.77 ± 3.17 mm2 , while mean vFFR was 0.87 ± 0.09. A correlation was observed between vFFR and LMCA MLA (r = .792, p = .001). The diagnostic accuracy of vFFR ≤0.8 in identifying lesions with MLA < 6.0 mm2 (sensitivity 98%, specificity 71.4%, area under the curve (AUC) 0.95, 95% confidence interval (CI) 0.89-1.00, p = .001) was good. CONCLUSIONS: In patients with good quality angiographic visualization of LMCA and available complete LMCA IVUS footage, 3D-QCA based vFFR assessment of LMCA disease correlates well to LMCA MLA as assessed by IVUS.

A case-vignette based assessment of patient's perspective on coronary revascularization strategies, the OPINION study.

BACKGROUND AND AIMS: Significant left main (LM) stem disease is potentially life-threatening and mandates revascularization. This study aimed to assess how patients rate the importance of particular features of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), how this determines their preference for a particular treatment strategy, and whether particular personality characteristics influence this preference. METHODS AND RESULTS: In total, 1145 patients who visited the outpatient clinic of the Erasmus Medical Center for stable coronary artery disease were asked to complete a case vignette-questionnaire on a hypothetical significant LM stenosis amenable to PCI or CABG. To assess the individual's personality disposition and general distress level, each patient had to complete a set of 3 standardized, validated questionnaires with satisfactory psychometric properties. Overall 89% of patients preferred PCI to CABG. PCI was the preferred strategy despite a higher risk for repeat revascularization and need for more medication. Remarkably, the fact that a risk for repeat revascularization is more common in the PCI group is less important for the patients who opt for PCI. Risk for stroke and bleeding were the most important arguments to opt for PCI over CABG. Type D personality, depression, and anxiety were all associated with a relatively higher preference for CABG as revascularization strategy. CONCLUSION: Overall, when given the choice patients seem to have a clear preference for PCI over CABG and consider stroke and bleeding important procedure-related complications. Patients with Type D personality, depression, or anxiety favor CABG.

Navvus FFR to reduce CONTRAst, Cost and radiaTion (CONTRACT); insights from a single-centre clinical and economical evaluation with the RXi Rapid-Exchange FFR device.

OBJECTIVES: To assess whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. BACKGROUND: FFR is the mainstay of functional hemodynamic assessment of coronary artery lesions. The RXi Navvus system (ACIST Medical Systems, Eden Prairie, MN) is a monorail microcatheter with FFR-measurement capability through optical pressure sensor technology. METHODS: This is an investigator-initiated, prospective, single-center, observational cohort study. A total of 238 patients were enrolled, 97 patients with Navvus and 141 with conventional pressure-wire based FFR (PW-FFR). Final analyses were performed on the cohort in which only 1 device was used (82 Navvus procedures vs. 136 PW-FFR procedures). RESULTS: No significant differences were found in the total amount of contrast used (150±77 vs 147±79ml; p=0.81), radiation use (6200±4601 vs. 5076±4655 centiG∗cm2; p=0.09) or costs (€1994,- vs. €1930,-; p=0.32) in the Navvus vs. PW-FFR groups respectively. CONCLUSIONS: No significant differences were found in the amount of contrast used, total procedural costs or radiation when the Navvus system was used as compared to conventional FFR wires. CONDENSED ABSTRACT: CONTRACT is an investigator-initiated, prospective, single-center, observational cohort study that evaluated whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. Use of the RXi Navvus system was associated with comparable procedural costs, amount of radiation and contrast used as compared to PW-FFR systems.