Author + information
- Received February 17, 2017
- Revision received July 5, 2017
- Accepted July 10, 2017
- Published online December 18, 2017.
- Joo Myung Lee, MD, MPH, PhDa,
- Eun-Seok Shin, MD, PhDb,c,
- Chang-Wook Nam, MD, PhDd,
- Joon-Hyung Doh, MD, PhDe,
- Doyeon Hwang, MDf,
- Jonghanne Park, MDf,
- Kyung-Jin Kim, MDf,
- Jinlong Zhang, MDf,
- Chul Ahn, PhDg and
- Bon-Kwon Koo, MD, PhDf,h,∗ ()
- aDivision of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- bDepartment of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, South Korea
- cDivision of Cardiology, Dietrich Bonhoeffer Hospital, Academic Teaching Hospital of University of Greifswald, Greifswald, Germany
- dDepartment of Medicine, Keimyung University Dongsan Medical Center, Daegu, South Korea
- eDepartment of Medicine, Inje University Ilsan Paik Hospital, Goyang, South Korea
- fDepartment of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, Seoul, Korea
- gDivision of Biostatistics, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland
- hInstitute on Aging, Seoul National University, Seoul, Korea
- ↵∗Address for correspondence:
Dr. Bon-Kwon Koo, Department of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, 101 Daehang-ro, Chongno-gu, Seoul 110-744, Korea.
Objectives The authors investigated 2-year clinical outcomes according to fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) values in deferred lesions.
Background Invasive physiological indices such as FFR or iFR are used in clinical practice to select ischemia-causing stenosis and to guide the treatment strategy for patients with coronary artery disease.
Methods From the 3V FFR-FRIENDS (3-Vessel Fractional Flow Reserve for the Assessment of Total Stenosis Burden and Its Clinical Impact in Patients With Coronary Artery Disease) study, 821 deferred lesions (n = 374) with both FFR and iFR available were included in this study. The primary outcome was major adverse cardiac events (MACE) (a composite of cardiac death, myocardial infarction, and ischemia-driven revascularization) at 2 years. The lesions were classified according to FFR and iFR cutpoints into concordant normal (Group 1: FFR >0.80 and iFR >0.89), high FFR and low iFR (Group 2: FFR >0.80 and iFR ≤0.89), low FFR and high iFR (Group 3: FFR ≤0.80 and iFR >0.89), and concordant abnormal (Group 4: FFR ≤0.80 and iFR ≤0.89).
Results Deferred lesions with low FFR (≤0.80) or low iFR (≤0.89) showed significantly higher rates of 2-year MACE, compared with high FFR (>0.80) or high iFR (>0.89), respectively (7.2% in low FFR vs. 2.4% in high FFR; p < 0.001; 8.1% in low iFR vs. 2.4% in high iFR; p < 0.001). Both FFR and iFR showed significant association with occurrence of MACE as continuous values (hazard ratio [HR] of FFR: 0.570, 95% confidence interval [CI]: 0.337 to 0.963; p < 0.001; HR of iFR: 0.350, 95% CI: 0.217 to 0.567; p < 0.001). When comparing the discriminant ability between FFR and iFR, the c-index was comparable between FFR and iFR (c-index 0.677 vs. 0.685; p = 0.857). Among 4 groups classified according to FFR and iFR levels, only Group 4 with concordant abnormal results showed significantly higher risk of MACE, compared with group 1 (HR: 7.708, 95% CI: 2.621 to 22.667; p < 0.001).
Conclusions Both FFR and iFR showed significant association with future risk of MACE in deferred lesions. The discordant results between FFR and iFR were not associated with the increased risk of MACE. The risk of MACE was significantly increased only in lesions with abnormal results of both FFR and iFR.
- coronary artery disease
- fractional flow reserve
- instantaneous wave free ratio
Dr. Koo has received an institutional research grant from St. Jude Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received February 17, 2017.
- Revision received July 5, 2017.
- Accepted July 10, 2017.
- 2017 American College of Cardiology Foundation
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