Author + information
- Jonghanne Park1,
- Joo Myung Lee2,
- Eun-Seok Shin3,
- Chang-Wook Nam4,
- Joon-Hyung Doh5,
- Doyeon Hwang6,
- Tae-Min Rhee7,
- Chee Hae Kim6,
- Jung-Kyu Han6,
- Han-Mo Yang8,
- Bon-Kwon Koo6 and
- Hyo-Soo Kim6
- 1Ministry of Health and Welfare, Seoul, Korea, Republic of
- 2Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, Republic of
- 3Ulsan University Hospital, Ulsan, Korea, Republic of
- 4Keimyung University Dongsan Medical Center, Daegu, Korea, Republic of
- 5Inje University Ilsan Paik Hospital, Seoul, Korea, Republic of
- 6Seoul National University Hospital, Seoul, Korea, Republic of
- 7National Maritime Medical Center, Seoul, Korea, Republic of
- 8Seoul National University Hospital, Seoul, Korea, Republic of
Angiographically insignificant coronary stenosis with low fractional flow reserve (FFR) is associated with poor clinical outcome. However, the mechanism of this visual-functional discordance is not fully understood. We utilized quantitative plaque analysis with coronary computed tomography angiography (cCTA) to evaluate the total atherosclerotic plaque burden in coronary vessels with visual-functional mismatch.
Total 798 vessels with available cCTA at the time of invasive angiography and FFR measurement were eligible for the analysis. According to angiographic percent diameter stenosis (%DS) and FFR, vessels were divided into ‘Concordantly normal’ (%DS < 50% and FFR > 0.8), ‘Mismatch’ (%DS < 50% and FFR > 0.8), ‘Reverse Mismatch’ (%DS < 50% and FFR ≤ 0.8) and ‘Concordantly abnormal’ (%DS < 50% and FFR ≤ 0.8). Total atherosclerotic plaque burden was quantified with the per-vessel percent aggregate plaque volume (%APV). We calculated the difference between reference diameters (RD) measured by cCTA and QCA (ΔRD = RDcCTA - RDQCA) as an index for the diffuse atherosclerotic burden undetected by conventional angiography.
7.1% (57 lesions) of lesions had FFR ≤ 0.8 and %DS < 50% (Reverse mismatch), while 15.3% (122 lesions) and 18.0% (144 lesions) of lesions were ‘Mismatch’ and ‘Concordantly abnormal’. The per-vessel %APV of ‘Reverse Mismatch’ (22.1% ± 13.5) group was significantly larger than ‘Mismatch’ (16.7% ± 13.0, p = 0.037) group or ‘Concordantly normal’ (10.2% ± 11.6, p < .001) group. The per-vessel %APV of ‘Reverse mismatch’ group was comparable to the per-vessel %APV of ‘Concordantly normal’ group (23.2% ± 13.3, p = 0.94). Lesions in ‘Reverse mismatch’ group had smaller RDQCA (2.7mm ± 0.5) and greater ΔRD (0.8mm ± 0.8) compared to lesions in ‘Mismatch’ (0.4mm ± 0.8, p = 0.001) or ‘Concordantly normal’ (0.3mm ± 0.8, p = 0.046) groups. A multi-level mixed effect model adjusted by age, sex, lesion location and the time interval between the two measurements showed consistent difference between groups.
The mechanism of low FFR and angiographically insignificant stenoses can be attributed to the diffuse plaque burden undetected by coronary luminogram.
IMAGING: FFR and Physiologic Lesion Assessment