Impact of Poststenting Fractional Flow Reserve on Long-Term Clinical Outcomes

Abstract

Background: Fractional flow reserve (FFR)-guided treatment has been demonstrated to improve percutaneous coronary intervention (PCI) results. However, little is known on the long-term impact of low post-PCI FFR. Methods: This is a large prospective all comers study evaluating the impact of post-PCI FFR on clinical outcomes. All patients undergoing successful PCI were eligible for enrollment. FFR measurements were performed immediately after PCI when the operator considered the angiographic result acceptable and final. No further action was undertaken based on the post-PCI result. Suboptimal post-PCI FFR was defined as FFR<0.90. The primary end point was major adverse cardiac events, a composite of cardiac death, any myocardial infarction, or any revascularization at 2-year follow-up. Secondary end points were target vessel revascularizations and stent thrombosis and the separate components of the primary end point. Results: A total of 1000 patients were enrolled. Post-PCI FFR was successfully measured in 1165 vessels from 959 patients. A poststenting FFR<0.90 was observed in 440 vessels (37.8%). A total of 399 patients had at least 1 vessel with FFR<0.90 post-PCI. At 2-year follow-up, a patient level analysis showed no association between post-PCI FFR and major adverse cardiac event (hazard ratio [HR], 1.08 [95% CI, 0.73–1.60], P =0.707), cardiac death (HR, 1.55 [95% CI, 0.72–3.36], P =0.261), any myocardial infarction (HR, 1.53 [95% CI, 0.78–3.02], P =0.217). A vessel level analysis showed a higher rate of target vessel revascularization (HR, 1.91 [95% CI, 1.06–3.44], P =0.030) and a tendency toward higher rate of stent thrombosis (HR, 2.89 [95% CI, 0.88–9.48], P =0.081) with final post-PCI FFR<0.90. Conclusions: Suboptimal post-PCI FFR has only a moderate impact on major adverse cardiac event but coronary arteries with a post-PCI FFR<0.90 have a higher rate of target vessel revascularization.

Residual Quantitative Flow Ratio to Estimate Post‐Percutaneous Coronary Intervention Fractional Flow Reserve

“…In the present study, 10% of the revascularized vessels had a post-PCI FFR ≤ 0.80 and 42% had a suboptimal PCI result (FFR < 0.90). These rates are in line with the study of Diletti et al, in which 7.7% and 37.8% of the vessels had a post-PCI FFR ≤ 0.80 and < 0.90, respectively [ 23 ]. Interestingly, vessels with an unsatisfactory post-PCI FFR might be amenable to additional interventions (e.g., post‐dilation or additional stent placement) that can augment FFR [ 9 , 19 ].…”

“…The increase in FFR that is achieved by revascularization is directly associated with restoration of myocardial perfusion as measured by [ 15 O]H 2 O positron emission tomography and is related to the extent of symptomatic relieve [ 7 , 22 ]. Nevertheless, in some patients, an angiographically successful PCI does not leads to an FFR above the “ischemic” threshold (FFR > 0.80), which may partly explain that 20–30% of patients report recurrent angina 1 year post-PCI [ 1 , 5 , 9 , 20 , 23 , 24 ]. In the present study, 10% of the revascularized vessels had a post-PCI FFR ≤ 0.80 and 42% had a suboptimal PCI result (FFR < 0.90).…”

“…Rimac et al have attempted to define a post-PCI threshold in a meta-analysis of 59 studies and demonstrated that a post-PCI FFR < 0.90 was associated with an increased risk of repeat revascularization and major adverse cardiac events (MACE) [ 8 ]. Recently, Diletti et al assessed this prognostic threshold among 959 patients with post-PCI FFR and showed that the cutoff was associated with target-vessel revascularization [ 23 ]. In line with these publications, a post-PCI FFR < 0.90 was used to define a suboptimal PCI result in our study.…”

Diagnostic Accuracy of Coronary Angiography-Based Vessel Fractional Flow Reserve (vFFR) Virtual Stenting

“…The ‘Virtual stenting’ vFFR study is an observational, single-center cohort study aiming to evaluate the diagnostic performance of offline pre-PCI angiogram-based estimation of final functional PCI outcome—namely residual vFFR—against invasively measured post-PCI FFR. A consecutive cohort of the 200 most recent patients enrolled in the FFR SEARCH registry who underwent PCI with stenting were screened for eligibility [ 31 , 32 ]. The detailed study design and protocol of FFR SEARCH registry have been previously described [ 31 ].…”

“…A consecutive cohort of the 200 most recent patients enrolled in the FFR SEARCH registry who underwent PCI with stenting were screened for eligibility [ 31 , 32 ]. The detailed study design and protocol of FFR SEARCH registry have been previously described [ 31 ]. In brief, FFR SEARCH was a prospective registry in which FFR values were routinely collected after successful PCI in 1000 consecutive patients between March 2016 and May 2017.…”