Why carry out this study? |
The role of coronary physiology testing is less clear among certain patients’ groups with coronary artery disease. |
What did the study ask? |
What is the available evidence regarding the utility of coronary physiology testing in patients with serial coronary lesions, acute coronary syndrome (ACS), aortic stenosis (AS), heart failure, as well as post-percutaneous coronary intervention (PCI)? |
What was learned from the study? |
In patients with serial non-left main coronary lesions, instantaneous wave-free ratio (iFR) is the preferred modality for assessing coronary physiology. |
The use of fractional flow reserve (FFR) in evaluating non-culprit lesions among patients with ST-elevation myocardial infarction is feasible and would reduce adverse events compared with culprit-only approach. |
A post-PCI FFR or IFR can predict adverse events, but the role of physiology-guided optimization approach in improving clinical outcomes is being evaluated. In patients with acute heart failure, FFR-guided revascularization is feasible in most patients. |
In patients with AS, borderline values of FFR are harder to interpret, and should be re-evaluated after treatment of AS. |
Introduction
Physiological Testing with FFR and iFR
Current Data for the Use of FFR and iFR
Use of FFR in Specific Groups of Patients
FFR in Acute Coronary Syndrome
Study | Year | Design | Patients (n) | Study groups | ACS (%) | FFR cutoff | Definition of primary outcome | Follow-up period | Outcomes |
---|---|---|---|---|---|---|---|---|---|
COMPARE-ACUTE | 2017 | Prospective, multicenter, randomized control trial | 885 | FFR-guided complete revascularization versus culprit-only approach | 100% STEMI | ≤ 0.80 | MACCE: Composite of all-cause mortality, MI, cerebrovascular accident and repeat ischemia-driven revascularization | 1 year | Lower MACE in FFR-guided group (HR 0.35; 95% CI 0.22–0.55) |
DANAMI-3- PRIMULTI | 2015 | Prospective, multicenter, randomized control trial | 627 | FFR-guided complete revascularization versus culprit-only approach | 100% STEMI | ≤ 0.80 | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 27 months | Lower MACE in FFR-guided group (HR 0.56; 95% CI 0.38–0.83) |
FAME | 2015 | Prospective, multicenter, randomized control trial | 1005 | Angiography-guided versus FFR-guided revascularization | 32.6% patients had NSTEMI (CK < 1000 U/I) or Unstable angina | ≤ 0.80 | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 5-year | 2-year: Trend to lower risk of MACE with FFR guidance (RR 0.80; 95% CI 0.62–1.02) + no subgroup difference between SIHD [ARR 3.7%] or ACS [ARR 5.1%]. 5-year no difference in MACE (RR 0.91; 95% CI 0.75–1.10) + no subgroup difference between SIHD and ACS (pinteraction = 0.97) |
FUTURE | 2021 | Prospective, multicenter, randomized control trial | 927 | Angiography-guided versus FFR-guided revascularization | 45% with ACS | ≤ 0.80 | MACCE: Composite of all-cause mortality, MI, cerebrovascular accident and repeat ischemia-driven revascularization | 1 year | No difference in MACCE (HR 0.97; 95% CI 0.69–1.36). No subgroup difference between ACS (HR 1.03; 95% CI 0.61–1.73) and SA (HR 0.96; 95% CI 0.60–1.54) |
FAMOUS NSTEMI | 2015 | Prospective, multicenter, randomized control trial | 350 | Angiography-guided versus FFR-guided revascularization | 100% NSTEMI | ≤ 0.80 | MACCE: Composite of all-cause mortality, MI, cerebrovascular accident and repeat ischemia-driven revascularization | 1 year | No difference in MACCE (risk difference – 1.8%; 95% CI: – 7.9, 4.2%) |
FLOWER MI | 2021 | Prospective, multicenter, randomized control trial | 1163 | Angiography-guided versus FFR-guided revascularization | 100% STEMI | ≤ 0.80 | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 1 year | No difference in MACE (HR 1.32; 95% CI 0.78–2.23) |
PRIME FFR | 2008–2013 | Prospective, international multicenter registry | 1983 | Single arm for FFR-guided revascularization | 27% ACS | ≤ 0.80 | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 1 year | Among ACS group, MACE after FFR-guided reclassification of management was similar to non-reclassified patients (8.0 vs. 11.6%; p = 0.20) |
POTVIN et al. | 2002–2004 | Prospective single-center study | 201 | Single arm for FFR-guided revascularization | 62% ACS | ≤ 0.75 | MACE: Composite of cardiovascular mortality, MI, and repeat ischemia-driven revascularization | 11-month | No difference in MACE among ACS vs. SIHD (9 vs. 13%, p = 0.44) and among patients with and without lesions associated with positive noninvasive test results (9 vs. 10%, p = 1.00) |
Fischer et al. | 2002–2004 | Single-center retrospective observational | 111 | Single arm for FFR-guided revascularization | 32% | ≤ 0.75 | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 1 year | No difference in MACE among ACS vs. SIHD (28.6 vs. 17.1%, p = 0.21) |
Mehta et al. | 2002–2010 | Single-center retrospective observational | 674 | Patients with deferred revascularization based on FFR in the setting of ACS versus non-ACS | 49.60% | ≤ 0.80 | MACE: Composite of cardiovascular mortality, MI, and repeat ischemia-driven revascularization in deferred lesions | 4.5 years | Among ACS patients with deferred revascularization, every 0.01 decrease in FFR was associated with higher MACE (HR 1.08; 95% CR 1.03–1.12) |
Hakeem et al. | 2009–2014 | Single-center retrospective observational | 576 | Patients with deferred revascularization based on FFR in the setting of ACS versus non-ACS | 35.80% | ≤ 0.75 | Composite of MI or target vessel failure | 3.4 years | Among patients with deferred revascularization, MACE was higher in ACS vs. SIHD (25 vs. 12%; p < 0.001) |
Lee et al. | 2003–2011 | Multicenter, prospective, registry | 1596 | Patients with deferred revascularization based on FFR in the setting of NSTEACS versus SIHD | 18.9% NSTEACS | ≤ 0.80 | MACE: Composite of cardiovascular mortality, MI, and repeat ischemia-driven revascularization | 2-year | Among patients with deferred revascularization, MACE was higher in ACS vs. SIHD (HR 3.0; 95% CI 1.23–7.17) |
Post-PCI FFR
Study | Year | Design | Patients (n) | Study groups | Definition of primary outcome | Follow-up period | Outcomes |
---|---|---|---|---|---|---|---|
Pijls et al. | 2002 | Retrospective multicenter registry | 750 | Patients undergoing routine PCI who had post-PCI FFR measurements | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 6 months | Post-PCI FFR most significant independent variable correlating with MACE |
Nam et al. | 2011 | Retrospective single-center registry | 80 | Patients undergoing routine PCI who had post-PCI FFR measurements | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 12 months | MACE correlated with post-PCI FFR < 0.9 (AUC: 0.69) |
Leesar et al. | 2011 | Retrospective single-center registry | 66 | Among patients who underwent PCI for baseline FFR < 0.75, post-PCI FFR was measured | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 24 months | MACE-free survival lower in patients with final FFR < 0.96 (72 vs. 94%; p = 0.02) |
Ito et al. | 2014 | Retrospective single-center registry | 97 | Patients undergoing routine PCI who had post-PCI FFR measurements | MACE: Composite of cardiovascular mortality, MI, stent thrombosis and target vessel revascularization | 17.8 months | MACE correlated with post-PCI FFR < 0.9 (AUC: 0.82) |
Reith et al. | 2015 | Prospective single-center analysis | 66 | Patients undergoing PCI for de novo lesions, underwent post-PCI FFR and OCT assessment | MACE: Composite of all-cause mortality, MI, and repeat ischemia-driven revascularization | 15.11 months | MACE correlated with post-PCI FFR < 0.9 (AUC: 0.77) |
DK-CRUSH VI | 2015 | Prospective, multicenter, randomized control trial | 320 | Angiography-guided versus FFR-guided revascularization for patients with single true coronary bifurcation lesion | MACE: Composite of cardiovascular mortality, MI, and repeat ischemia-driven revascularization | 12 months | No difference in MACE (HR 0.91; 95% CI 0.48–1.88) |
Agarwal et al. | 2016 | Retrospective single-center registry | 574 | Patients undergoing routine PCI, who had post-PCI FFR measurements | MACE: Composite of all-cause mortality, MI, and target vessel revascularization | 31 months | MACE correlated with post-PCI FFR < 0.86 |
DK-CRUSH VII | 2017 | Prospective multicenter analysis | 1476 | Among patients who underwent PCI for baseline FFR < 0.80, post-PCI FFR was measured | Target vessel failure: cardiac mortality, target vessel-related MI, and TVR | 36 months | Post-PCI FFR ≤ 0.88 was the only predictor of TVF (≤ 0.91 for LAD) |
Piroth et al. | 2017 | Retrospective analysis from prospective multicenter clinical trials | 639 | All patients of FAME 1 and FAME 2 who had post-PCI FFR measurement were included | Vessel-related cardiovascular mortality, vessel-related spontaneous MI, and ischemia-driven target vessel revascularization | 24 months | Post-PCI FFR of 0.92 had highest diagnostic accuracy for predicting adverse events; but with low specificity (43%) and sensitivity (75%) |
Azzalini et al. | 2019 | Prospective single-center analysis | 95 | Among patients who underwent PCI for baseline FFR < 0.80, post-PCI FFR was measured | MACE: Composite of cardiovascular mortality, MI, readmission for angina and repeat ischemia-driven revascularization | 12 months | MACE higher in patients with final FFR < 0.90 (31.6 vs. 9.1%; p = .047) |
Hwang et al. | 2019 | Prospective multicenter registry | 835 | Patients undergoing PCI with DES, who had post-PCI FFR measurements | Target vessel failure: cardiac mortality, target vessel-related MI, and TVR | 24 months | Post-PCI FFR predicted TVF, with cutoff of 0.82 and 0.88 in the LAD and non-LAD |
FFR-SEARCH | 2020 | Prospective multicenter analysis | 959 | Among patients who underwent PCI, post-PCI FFR was measured at the end of the procedure | MACE: Composite of cardiovascular mortality, MI, and repeat ischemia-driven revascularization | 24 months | Patient-level analysis showed no association between MACE and post-PCI FFR. Vessel-level analysis showed higher TVR with FFR < 0.90 |
TARGET-FFR | 2021 | Prospective, single-center, randomized control trial | 260 | After angiographically guided PCI, patients were randomized to receive a physiology-guided incremental optimization strategy or a blinded coronary physiology assessment (control group) | Proportion of patients with a final post-PCI FFR > 0.90 | In-hospital | No difference in primary outcome; but FFR-guided optimization reduced the proportion of patients with a final FFR < _0.80 (− 11.2%, 95% CI − 21.87 to − 0.35, p = 0.045) |
Role of FFR in serial lesions
Study | Year | Design | Study group(s) | Patients (n) | Lesions (n) | FFR cutoff | ACS (%) | MVD (%) | Stents implanted (n) | Deferred lesions (%) | Follow-up period (days) | MACE definition | Study outcomes |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Candreva et al. | 2021 | Prospective multicenter study | One group: FFR was measured using motorized pullback pressure recordings in patients who had serial intermediate coronary stenoses | 23 | 51 | 0.8 | NR | 73.9 | NR | NR | None | NR | Three patterns of FFR pullback curves were identified; no step up, 1 step up, and 2 step ups |
Modi et al. | 2020 | Prospective | One group: apparent FFR, true FFR, Pd/Pa and iFR were measured in patients with serial lesions using manual pullback. Additionally, the predicted FFR was calculated using a novel equation | 54 | NR | 0.8 | NR | NR | NR | NR | None | NR | Stenosis misclassification rates based on FFR 0.80, iFR 0.89, and Pd/Pa 0.91 thresholds were not significantly different (17, 24, and 20%, respectively) but were higher than predicted FFR (11%, p < 0.001) |
Kim et al. | 2012 | Prospective multicenter study | One group: FFR measurements with pullback pressure recordings in patients who had serial intermediate coronary stenoses | 131 | 298 | 0.8 | 22.1 | 66.1 | 116 | 61.1 | 501 ± 311 | Cardiac death, target vessel-related MI, and TVR | TLR of stented lesion: 1, TLR of deferred lesion: 0 Cardiac death: 0 Target vessel related MI: 0, nontarget vessel related MI: 1 |
Pijls et al. | 2000 | Prospective | One group: apparent FFR, predicted FFR and true FFR were measured in patients undergoing PTCA and had ≥ 2 serial stenoses | 32 | 64 | NR | NR | NR | 36 | 43.75 | None | NR | Compared with true FFR, the percent differences were 4 ± 0% for predicted FFR and 11 ± 12% for apparent FFR. The differences between apparent FFR and true FFR were larger for the proximal stenosis than for distal stenosis (14 ± 16% versus 9 ± 8%, respectively; p < 0.01) |
Serial Lesions Involving Left Main Coronary Artery Disease
Role of FFR in Aortic Stenosis
Study | Year | Design | Patients (n) | Study group(s) | FFR cut off | Method of adenosine administration | Degree of AS | Treatment of AS | Follow-up period | MACE definition | Outcomes |
---|---|---|---|---|---|---|---|---|---|---|---|
Stundl et al. | 2020 | Prospective study | 246 | One group: FFR measured before TAVR and 6–8 weeks after TAVR. FFR-positive intermediate lesions were left untreated in the first instance; 6–8 weeks following TAVR, both the coronary angiography and the FFR measurement were repeated. Revascularization was then performed according to the FFR values after successful TAVR | 0.8 | IV infusion | Severe | TAVR | 1 year | NR | No significant difference between FFR pre and post TAVR (0.77 ± 0.04 vs. 0.76 ± 0.08; p = 0.11) 1-year all-cause mortality 8.5%, stroke 1.6%, MI 0% |
Scarsini et al. | 2019 | Retrospective study | 268 | Patient with AS who underwent FFR assessment (n = 137) vs. those without AS (n = 154) | 0.8 | IV infusion or IC boluses | Moderate and Severe | NR | NR | NR | In propensity-matched analysis, no difference in FFR between severe AS vs. mod AS vs. no AS (0.81 ± 0.11 vs. 0.81 ± 0.08 vs. 0.80 ± 0.1, p = 0.72) |
Ahmad et al. | 2018 | Prospective study | 28 | One group: FFR/iFR measurements were done before and immediately after TAVR | NR | IC boluses | Severe | TAVR | NR | NR | FFR decreased post TAVR (0.87 ± 0.08 pre-TAVR vs. 0.85 ± 0.09 post-TAVR; p < 0.01) iFR did not change post TAVR (0.88 ± 0.09 pre-TAVR vs. 0.88 ± 0.09 post-TAVR; p = 0.73) |
Scarsini et al. | 2017 | Retrospective study | 252 | FFR/iFR measured in patients with severe AS (n = 85) vs. in those without AS (n = 167) | 0.8 | IC boluses | Severe | TAVR | NR | NR | Using the 0.89 iFR cut-off, the diagnostic accuracy of iFR was significantly lower in AS vs. no AS (76.3 vs. 86.1%, p < 0.01) Best iFR cut-off in predicting FFR < 0.80 in patients with AS was 0.83 |
Gioia et al. | 2016 | Retrospective study | 318 | Patients with AS who underwent FFR-guided revascularization n = 106 vs. who underwent angio-guided revascularization (n = 212) | 0.8 | NR | Moderate and Severe | SAVR | 5 years | All-cause mortality, MI, and repeat revascularization | No differences were found between both groups in terms of MACE (38 vs. 39%, p = 0.98) and other study outcomes (mortality, MI, revascularization, AVR) |
Pesarini et al. | 2016 | Prospective study | 54 | One group: FFR measured before and immediately after TAVR | 0.8 | IC boluses | Severe | TAVR | 30 days | All-cause mortality, MI, stroke, angina, rehospitalization due to angina at rest or heart failure | Overall, FFR did not change post TAVR (0.89 ± 0.10 pre versus 0.89 ± 0.13 post; p = 0.73) Positive FFR values worsened after TAVR (0.71 ± 0.11 versus 0.66 ± 0.14) Conversely, negative FFR values improved after TAVR (0.92 ± 0.06 versus 0.93 ± 0.07) No MACE during follow-up |
Role of FFR in Heart Failure
Study | Year | Design | Patients (n) | Study group(s) | FFR cut off | Follow-up period | Mean Pra | Outcomes |
---|---|---|---|---|---|---|---|---|
Digioia et al. | 2020 | Retrospective single-center analysis | 1299 | FFR-guided revascularization in patients with LVEF < 50% vs. matched group undergoing angiography-guided revascularization | 0.8 | 60 months | NR | MACCE was lower at 5-year in FFR-guided versus angiography-guided groups (HR 0.81; 95% CI 0.67–0.97) |
Toth et al. | 2016 | Prospective, single-arm study | 1235 | One group: FFR was measured with and without Pra in patients who underwent LHC/RHC with FFR measurement in at least one coronary stenosis | NR | None | 7 (median) | The median difference between FFR and FFRmyo was 0.01 (IQR: 0.01–0.02) Out of 1146 stenoses with an FFR > 0.80, none had an FFRmyo < 0.75, and 110 (9%) stenoses had an FFRmyo < 0.80 |
Layland et al. | 2013 | Prospective, single-arm study | 42 | One group: FFR was measured with and without Pra in patients undergoing elective PCI | 0.8 | None | 9.1 | The mean FFR was significantly lower when Pra was included in the calculation (FFRmyo 0.77 ± 0.19 vs. FFR 0.80 ± 0.16, p < 0.001) An additional nine patients (21%) would have been reclassified as having an FFR ≤ 0.8 if Pra was incorporated into FFR calculation before PCI |
Perera et al. | 2004 | Prospective, single-arm study | 66 | One group: FFR was measured with and without Pra | 0.75 | None | 5.5 | 12 functionally significant stenoses (14% of all lesions) were misclassified as insignificant when Pra was ignored The sensitivity of FFR for detecting significant coronary lesions was reduced to 64% when Pra was ignored |