Randomized Comparison of Fractional Flow Reserve and Instantaneous Wave Free Ratio in Serial Disease
Authors' conclusion
FFR and iFR pullback gradients overestimate the benefit of target lesion PCI and can miss residual ischemia in one-third of patients.
Study context
- Population
- Patients with a focal target lesion and a second focal lesion or diffusely diseased segment in the same vessel (serial or diffuse disease)
- Participants
- 87 patients
- Comparison
- Fractional flow reserve (FFR) vs iFR
- FFRn = 45
- iFRn = 42
- Primary endpoint
- Error in predicted post-PCI physiology vs actual values
- Follow-up
- After target lesion PCI
Methodological detailsoperators blinded to one modality
- Operators blinded to one modality
Primary result
As reported in the abstract
Predictive error of post-PCI physiology
Predictive error, FFRΔ
12%
6% to 17%
Predictive error, iFRΔ
4%
0% to 9%; P < 0.001
Predictive error, FFRcalc
−5%
−18% to 8%; P = 0.427
Further findings
Significant residual disease missed
- Missed with FFRΔ
- 36%
- Missed with iFRΔ
- 34%
- Missed with FFRcalc
- 14%
FFR and iFR at baseline and after target lesion percutaneous coronary intervention (PCI)
- Median FFR at baseline
- 0.70 (Q1-Q3: 0.62 to 0.78)
- Median iFR at baseline
- 0.81 (Q1-Q3: 0.68 to 0.90)
- Median FFR after target lesion PCI
- 0.82 (Q1-Q3: 0.74 to 0.87)
- Median iFR after target lesion PCI
- 0.89 (Q1-Q3: 0.83 to 0.93)
Original publication
Randomized Comparison of Fractional Flow Reserve and Instantaneous Wave Free Ratio in Serial Disease. JACC Cardiovasc Interv. Published 14 July 2025. doi:10.
Summarised from the published abstract; every number is checked against it