Author + information
- Received April 15, 2019
- Revision received June 12, 2019
- Accepted June 18, 2019
- Published online September 25, 2019.
- Seung Hun Lee, MD, PhDa,∗,
- Ki Hong Choi, MDa,∗,
- Joo Myung Lee, MD, MPH, PhDa,∗ (, )
- Doyeon Hwang, MDb,
- Tae-Min Rhee, MDb,
- Jonghanne Park, MDb,c,
- Hyun Kuk Kim, MD, PhDd,
- Yun-Kyeong Cho, MD, PhDe,
- Hyuck-Jun Yoon, MD, PhDe,
- Jinhyoung Park, PhDf,
- Young Bin Song, MD, PhDa,
- Joo-Yong Hahn, MD, PhDa,
- Joon-Hyung Doh, MD, PhDg,
- Chang-Wook Nam, MD, PhDe,
- Eun-Seok Shin, MD, PhDh,i,
- Seung-Ho Hur, MD, PhDe and
- Bon-Kwon Koo, MD, PhDb,j
- aDivision of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- bDepartment of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, Seoul, Korea
- cDepartment of Internal Medicine, Naju National Hospital, Ministry of Health and Welfare, Naju, Korea
- dDepartment of Internal Medicine and Cardiovascular Center, Chosun University Hospital, University of Chosun College of Medicine, Gwangju, Korea
- eDepartment of Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea
- fDepartment of Biomedical Engineering, Sungkyunkwan University, Suwon, Korea
- gDepartment of Medicine, Inje University Ilsan Paik Hospital, Goyang, Korea
- hDivision of Cardiology, Ulsan Hospital, Ulsan, Korea
- iDepartment of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea
- jInstitute on Aging, Seoul National University, Seoul, Korea
- ↵∗Address for correspondence:
Dr. Joo Myung Lee, Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Republic of Korea.
Objectives The study evaluated the physiologic characteristics of discordant lesions between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) and the prognosis at 5 years.
Background FFR or iFR have been standard methods for assessing the functional significance of coronary artery stenosis. However, limited data exist about the physiologic characteristics of discordant lesions and the prognostic implications resulting from these lesions.
Methods A total of 840 vessels from 596 patients were classified according to iFR and FFR; high iFR–high FFR (n = 580), low iFR–high FFR (n = 40), high iFR–low FFR (n = 69), and low iFR–low FFR (n = 128) groups, which were compared with a control group (n = 23). The differences in coronary circulatory indices including the coronary flow reserve (CFR), index of microcirculatory resistance (IMR), and resistance reserve ratio (RRR) (resting distal arterial pressure × mean transit time / hyperemic distal arterial pressure × hyperemic mean transit time), which reflect the vasodilatory capacity of coronary microcirculation, were compared. Patient-oriented composite outcomes (POCO) at 5 years including all-cause death, any myocardial infarction, and any revascularization were compared among patients with deferred lesions.
Results In the low iFR–high FFR group, CFR, RRR, and IMR measurements were similar to the low iFR–low FFR group: CFR 2.71 versus 2.43 (p = 0.144), RRR 3.36 versus 3.68 (p = 0.241), and IMR 18.51 versus 17.38 (p = 0.476). In the high iFR–low FFR group, the CFR, RRR, and IMR measurements were similar to the control group: CFR 2.95 versus 3.29 (p = 0.160), RRR 4.28 versus 4.00 (p = 0.414), and IMR 17.44 versus 17.06 (p = 0.818). Among the 4 groups, classified by iFR and FFR, CFR and RRR were all significantly different, except for IMR. However, there were no significant differences in the rates of POCO, regardless of discordance between the iFR and FFR. Only the low iFR–low FFR group had a higher POCO rate compared with the high iFR–high FFR group (adjusted hazard ratio: 2.46; 95% confidence interval: 1.17 to 5.16; p = 0.018).
Conclusions Differences in coronary circulatory function were found, especially in the vasodilatory capacity between the low iFR–high FFR and high iFR–low FFR groups. FFR–iFR discordance was not related to an increased risk of POCO among patients with deferred lesions at 5 years. (Clinical, Physiological and Prognostic Implication of Microvascular Status; NCT02186093; Physiologic Assessment of Microvascular Function in Heart Transplant Patients; NCT02798731)
- coronary artery disease
- coronary flow reserve
- fractional flow reserve
- instantaneous wave-free ratio
↵∗ Drs. Lee and Choi contributed equally to this work.
Dr. J.M. Lee has received research grant support from St. Jude Medical (Abbott Vascular) and Philips Volcano. Dr. Hahn has received research grant support from St. Jude Medical (Abbott Vascular). Dr. Koo has received institutional research grant support from St. Jude Medical (Abbott Vascular) and Philips Volcano. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received April 15, 2019.
- Revision received June 12, 2019.
- Accepted June 18, 2019.
- 2019 American College of Cardiology Foundation
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