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5-Year Outcomes of PCI Guided by Measurement of Instantaneous Wave-Free Ratio Versus Fractional Flow Reserve
Matthias Götberg1, Karolina Berntorp1, Rebecca Rylance1
1Department of Cardiology, Skåne University Hospital, Clinical Sciences, Lund University, Lund, Sweden.
Insights
The 5-year outcomes of instantaneous wave-free ratio (iFR)-guided revascularization were similar to fractional flow reserve (FFR)-guided procedures. This study found no significant differences in major adverse cardiac events for patients with coronary syndromes.
Area of Science:
- Cardiology
- Interventional Cardiology
- Clinical Trials
Background:
- The instantaneous wave-free ratio (iFR) is a key index for assessing coronary artery stenosis severity and guiding revascularization.
- While iFR has shown comparable short-term results to fractional flow reserve (FFR), long-term outcome data were previously limited.
Purpose of the Study:
- To evaluate the 5-year outcomes of the iFR-SWEDEHEART trial, comparing iFR-guided versus FFR-guided revascularization.
- The study focused on the composite endpoint of all-cause mortality, myocardial infarction, and unplanned revascularization in patients with chronic and acute coronary syndromes.
Main Methods:
- The iFR-SWEDEHEART trial was a multicenter, randomized clinical trial involving 2,037 patients.
- Patients were randomized to revascularization guided by either iFR or FFR, utilizing the Swedish Coronary Angiography and Angioplasty Registry.
Main Results:
- At 5-year follow-up, the primary composite endpoint occurred in 21.5% of the iFR group and 19.9% of the FFR group (Hazard Ratio: 1.09; 95% CI: 0.90-1.33).
- No significant differences were observed in all-cause death, nonfatal myocardial infarction, or unplanned revascularization rates between the iFR and FFR groups.
- Outcomes remained consistent across predefined subgroups, with no loss to follow-up.
Conclusions:
- In patients with coronary syndromes, iFR-guided revascularization demonstrated comparable 5-year outcomes to FFR-guided revascularization.
- The findings support the use of iFR as a viable alternative to FFR for guiding revascularization strategies.
Background:
Instantaneous wave-free ratio (iFR) is a coronary physiology index used to assess the severity of coronary artery stenosis to guide revascularization. iFR has previously demonstrated noninferior short-term outcome compared to fractional flow reserve (FFR), but data on longer-term outcome have been lacking.
Objectives:
The purpose of this study was to investigate the prespecified 5-year follow-up of the primary composite outcome of all-cause mortality, myocardial infarction, and unplanned revascularization of the iFR-SWEDEHEART trial comparing iFR vs FFR in patients with chronic and acute coronary syndromes.
Methods:
iFR-SWEDEHEART was a multicenter, controlled, open-label, registry-based randomized clinical trial using the Swedish Coronary Angiography and Angioplasty Registry for enrollment. A total of 2,037 patients were randomized to undergo revascularization guided by iFR or FFR.
Results:
No patients were lost to follow-up. At 5 years, the rate of the primary composite endpoint was 21.5% in the iFR group and 19.9% in the FFR group (HR: 1.09; 95% CI: 0.90-1.33). The rates of all-cause death (9.4% vs 7.9%; HR: 1.20; 95% CI: 0.89-1.62), nonfatal myocardial infarction (5.7% vs 5.8%; HR: 1.00; 95% CI: 0.70-1.44), and unplanned revascularization (11.6% vs 11.3%; HR: 1.02; 95% CI: 0.79-1.32) were also not different between the 2 groups. The outcomes were consistent across prespecified subgroups.
Conclusions:
In patients with chronic or acute coronary syndromes, an iFR-guided revascularization strategy was associated with no difference in the 5-year composite outcome of death, myocardial infarction, and unplanned revascularization compared with an FFR-guided revascularization strategy. (Evaluation of iFR vs FFR in Stable Angina or Acute Coronary Syndrome [iFR SWEDEHEART]; NCT02166736).
