Author + information
- Hyung Bok Park,
- Ryo Nakazato,
- Matthew Budoff,
- Jonathon Leipsic,
- Yuka Otaki,
- Daniel Berman and
- James Min
Fractional flow reserve (FFR) derived from coronary CT angiography (FFRCT) is a novel non-invasive method that demonstrates high performance for diagnosis of lesion-specific ischemia. FFRCT identifies ischemia-causing stenoses even among lesions that are non-obstructive (<50% stenosis) or intermediate in severity (30-69% stenosis). Adverse plaque characteristics (APC) by coronary CT angiography (CT)-including positive remodeling (PR), low attenuation plaque (LAP) and spotty intraplaque calcification (SC)-are associated with global myocardial ischemia and future acute coronary syndromes. Whether APCs by CT are associated with lesion-specific ischemia defined by FFRCT is unknown.
252 patients were studied with CT, FFRCT and invasive coronary angiography (ICA). The degree of lumen stenosis in 407 coronary lesions was evaluated by blinded CT (visual estimation; 0%, 1-29%, 30-49%, 50-69%, and 70-100%) and QCA (quantitative coronary angiography) core laboratories. Of these, 192 lesions (47%) were non-obstructive (<50% stenosis by CT; mean QCA = 38±14%) and 150 lesions (37%) were intermediate severity (30-69% stenosis by CT; mean QCA = 43±12%). CTs were evaluated for the presence of APCs as defined by: PR = maximal lesion vessel diameter/reference vessel diameter ≥1.1; LAP <30 HU within the coronary lesion; SC = intra-lesion nodular calcified plaques <3 mm. Lesion-specific ischemia was defined by FFRCT <0.80.
In non-obstructive lesions (<50%), mean FFRCT was 0.82±0.10 with ischemia identified in 39 lesions (18%). The identification of one or more APCs (PR, LAP or SC) was associated with lesion-specific ischemia by FFRCT in multivariate analysis [odds ratio (OR) 2.0, 95% confidence interval (CI) 1.03-3.9, p=0.04]. Similarly, in intermediate lesions (30-69%), mean FFRCT was 0.80±0.11, with ischemia identified in 64 lesions (42%). These ischemia-producing lesions had a two-fold higher likelihood of having APC than non-ischemia producing lesions (OR 2.1, 95% CI 1.1-4.3, p=0.036).
APCs by CT are associated with lesion-specific ischemia by FFRCT for both non-obstructive as well as intermediate coronary stenoses.
Poster Sessions, Expo North
Sunday, March 10, 2013, 3:45 p.m.-4:30 p.m.
Session Title: Imaging: CT/Multimodality VII
Abstract Category: 20. Imaging: CT/Multimodality
Presentation Number: 1269-345
- 2013 American College of Cardiology Foundation