Author + information
- Joo Myung Lee1,
- Eun-Seok Shin2,
- Chang-Wook Nam3,
- Joon-Hyung Doh4,
- Doyeon Hwang5,
- Jonghanne Park6,
- Ahn Chul7 and
- Bon-Kwon Koo5
- 1Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, Republic of
- 2Ulsan University Hospital, Ulsan, Korea, Republic of
- 3Keimyung University Dongsan Medical Center, Daegu, Korea, Republic of
- 4Inje University Ilsan Paik Hospital, Seoul, Korea, Republic of
- 5Seoul National University Hospital, Seoul, Korea, Republic of
- 6Ministry of Health and Welfare, Seoul, Korea, Republic of
- 7FDA-CDRH, Silver Spring, Maryland, United States
Invasive physiologic index such as fractional flow reserve (FFR) or instantaneous wave-free ratio (iFR) are used in clinical practice to select ischemia-causing stenosis and to guide the treatment strategy for patients with coronary artery disease. We investigated 2-year clinical outcomes according to FFR and iFR values in deferred lesions.
From 3V FFR-FRIENDS study, 821 deferred lesions (374 patients) with available both FFR and iFR 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 rates of MACE were compared according to FFR using cut-off value 0.80 and iFR using cut-off value 0.90. The rate of MACE was also compared among classifications according to FFR and iFR into concordant normal (Group 1: FFR>0.80 and iFR≥0.90), high FFR and low iFR (Group 2: FFR>0.80 and iFR<0.90), low FFR and high iFR (Group 3: FFR≤0.80 and iFR≥0.90) and concordant abnormal (Group 4: FFR≤0.80 and iFR<0.90).
Deferred lesions with low FFR (≤0.80) or low iFR (<0.90) showed significantly higher rates of 2-year MACE, compared with high FFR (>0.80) or high iFR (≥0.90), 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 (HR of FFR 0.570, 95% CI 0.337-0.963, p<0.001; HR of iFR 0.350, 95% CI 0.217-0.567, 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 2.621-22.667, p<0.001).
Both FFR and iFR showed significant association with future risk of MACE in deferred lesions. Among the 4 groups classified according to FFR and iFR values, the risk of MACE was significantly higher only in lesions with concordant abnormal results of both indices.
IMAGING: FFR and Physiologic Lesion Assessment