Author + information
- Pontus Andell1,
- Ole Frobert2,
- Evald Christiansen3,
- Ingibjorg Gudmundsdottir4,
- Lennart Sandhall5,
- David Erlinge6 and
- Matthias Götberg7
- 1Department of Cardiology, Lund University, Skåne University Hospital Lund, Lund, Sweden
- 2Universitetssjukhuset Orebro, Orebro, Sweden
- 3Aarhus University Hospital, Aarhus, Denmark
- 4University hospital Iceland, Reykjavik, Iceland
- 5Helsingborg Hospital, Helsingborg, Sweden
- 6Skane University Hospital, Lund, Sweden
- 7Department of Cardiology, Lund University, Skane University Hospital, Lund, Sweden
Instantaneous wave-free ratio (iFR) is an index used to measure the severity of coronary artery stenosis. iFR has been shown to be noninferior to fractional flow reserve (FFR) in two large prospective and randomized controlled trials. Reclassification of coronary revascularization strategy, i.e. how coronary physiology changes treatment decision is well-studied with FFR, but similar reports on iFR are lacking.
The iFR-SWEDEHEART study enrolled 2037 participants with stable angina or acute coronary syndrome with an indication for physiologically-guided assessment of coronary artery stenosis. Eligible patients were randomized to revascularization guided by either iFR or FFR. The treating interventionists had to enter both the preliminary treatment decision (i.e. optimal medical therapy (OMT), percutaneous coronary intervention (PCI) of one, two, or three vessels, or coronary artery bypass grafting (CABG)) based on the angiogram before iFR/FFR, and the final treatment decision determined by the iFR/FFR measurements.
A total of 1012 (iFR) and 1007 (FFR) patients underwent physiologically-guided revascularization. In the iFR and FFR groups, angiogram-based a priori strategies were OMT in 37.8% and 34.7%, PCI in 54.1% and 57.7% and CABG in 8.1% and 7.6%, respectively (p=0.25). All patients were mandatorily treated according to the iFR/FFR measurements. The iFR and FFR guided final treatment strategies were OMT in 46.9% and 43.3%, PCI in 43.9% and 45.4% and CABG in 9.2% and 11.3%, respectively. A total of 405 patients (40.1%) were reclassified with iFR and 409 patients (40.7%) were reclassified with FFR (p=0.78). The majority of reclassifications were deferrals of PCI into OMT in both the IFR (31.4%) and FFR (29.0%) groups, respectively (p=0.36).
Reclassification of coronary revascularization strategy using iFR or FFR was common and occurred in approximately 40% of patients. There were no significant differences in reclassification patterns between iFR or FFR and the most frequent reclassification was deferral of PCI in favor of OMT regardless of measurement modality.
IMAGING: FFR and Physiologic Lesion Assessment