Dataset Information

Association Between Adherence to Fractional Flow Reserve Treatment Thresholds and Major Adverse Cardiac Events in Patients With Coronary Artery Disease.

ABSTRACT:

Importance

Fractional flow reserve (FFR) is an invasive measurement used to assess the potential of a coronary stenosis to induce myocardial ischemia and guide decisions for percutaneous coronary intervention (PCI). It is not known whether established FFR thresholds for PCI are adhered to in routine interventional practice and whether adherence to these thresholds is associated with better clinical outcomes.

Objective

To assess the adherence to evidence-based FFR thresholds for PCI and its association with clinical outcomes.

Design, setting, and participants

A retrospective, multicenter, population-based cohort study of adults with coronary artery disease undergoing single-vessel FFR assessment (excluding ST-segment elevation myocardial infarction) from April 1, 2013, to March 31, 2018, in Ontario, Canada, and followed up until March 31, 2019, was conducted. Two separate cohorts were created based on FFR thresholds (≤0.80 as ischemic and >0.80 as nonischemic). Inverse probability of treatment weighting was used to account for treatment selection bias.

Exposures

PCI vs no PCI.

Main outcomes and measures

The primary outcome was major adverse cardiac events (MACE) defined by death, myocardial infarction, unstable angina, or urgent coronary revascularization.

Results

There were 9106 patients (mean [SD] age, 65 [10.6] years; 35.3% female) who underwent single-vessel FFR measurement. Among 2693 patients with an ischemic FFR, 75.3% received PCI and 24.7% were treated only with medical therapy. In the ischemic FFR cohort, PCI was associated with a significantly lower rate and hazard of MACE at 5 years compared with no PCI (31.5% vs 39.1%; hazard ratio, 0.77 [95% CI, 0.63-0.94]). Among 6413 patients with a nonischemic FFR, 12.6% received PCI and 87.4% were treated with medical therapy only. PCI was associated with a significantly higher rate and hazard of MACE at 5 years compared with no PCI (33.3% vs 24.4%; HR, 1.37 [95% CI, 1.14-1.65]) in this cohort.

Conclusions and relevance

Among patients with coronary artery disease who underwent single-vessel FFR measurement in routine clinical practice, performing PCI, compared with not performing PCI, was significantly associated with a lower rate of MACE for ischemic lesions and a higher rate of MACE for nonischemic lesions. These findings support the performance of PCI procedures according to evidence-based FFR thresholds.

SUBMITTER: Sud M

PROVIDER: S-EPMC7666430 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Amongst patients with suspected obstructive coronary artery disease (CAD), less than a third of patients have obstructive disease on invasive coronary angiography (ICA) and fewer still have flow-limiting obstructive disease as determined by invasive fractional flow reserve (FFR). FFR is a powerful tool in guiding revascularization of flow-limiting lesions which in turn improves clinical outcome in those with haemodynamically significant obstructive disease. However FFR is infrequently performed due to the cost, time and patient discomfort the procedure entails. Further advances in non-invasive imaging has allowed FFR to be derived non-invasively by applying computational fluid dynamic (CFD) modeling to the coronary computed tomography angiography (CCTA) dataset without the need to induce hyperemia or modify the standard CCTA acquisition protocol. FFR derived from CCTA has been shown to have excellent correlation with invasive FFR and remains diagnostically robust in presence of reduced signal-to-noise ratio (SNR), coronary calcification and motion artifact. More recently, new data have emerged evaluating the clinical impact of fractional flow reserve computed tomography (FFRCT) on the assessment and management of patients with stable chest pain. One such study is the Prospective LongitudinAl trial of FFRCT: Outcome and Resource IMpacts (PLATFORM) study which showed an improved patient selection for ICA using CCTA-FFRCT approach by increasing the likelihood of identifying obstructive CAD at ICA amongst those intended for invasive testing. CCTA-FFRCT may therefore serve as efficacious gatekeeper to ICA that enriches the ICA population. The utility of FFRCT has also helped deepened our understanding of CAD. Through CFD modeling, it is now recognized that there are mechanistic forces of wall shear stress (WSS) and axial plaque force acting on coronary plaques. This has created further interest in exploring the possible interplay between these mechanistic forces on the development of coronary plaque and vulnerability of these plaques to rupture.

Project description:BackgroundThere has been a gradual upward creep of revascularization thresholds for both fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR), before the clinical outcome trials for both indices. The increase in revascularization that has potentially resulted is at odds with increasing evidence questioning the benefits of revascularizing stable coronary disease. Using an independent invasive reference standard, this study primarily aimed to define optimal thresholds for FFR and iFR and also aimed to compare the performance of iFR, FFR, and resting distal coronary pressure (Pd)/central aortic pressure (Pa).Methods and resultsPd and Pa were measured in 75 patients undergoing coronary angiography±percutaneous coronary intervention with resting Pd/Pa, iFR, and FFR calculated. Doppler average peak flow velocity was simultaneously measured and hyperemic stenosis resistance calculated as hyperemic stenosis resistance=Pa-Pd/average peak flow velocity (using hyperemic stenosis resistance >0.80 mm Hg/cm per second as invasive reference standard). An FFR threshold of 0.75 had an optimum diagnostic accuracy (84%), whereas for iFR this was 0.86 (76%). At these thresholds, the discordance in classification between indices was 11%. The accuracy of contemporary thresholds (FFR, 0.80; iFR, 0.89) was significantly lower (78.7% and 65.3%, respectively) with a 25% rate of discordance. The optimal threshold for Pd/Pa was 0.88 (77.3% accuracy). When comparing indices at optimal thresholds, FFR showed the best diagnostic performance (area under the curve, 0.91 FFR versus 0.79 iFR and 0.77 Pd/Pa, P=0.002).ConclusionsContemporary thresholds provide suboptimal diagnostic accuracy compared with an FFR threshold of 0.75 and iFR threshold of 0.86 (cutoffs in derivation studies). Whether more rigorous thresholds would result in selecting populations gaining greater symptom and prognostic benefit needs assessing in future trials of physiology-guided revascularization.