Author + information
- Maros Ferencika,b,
- Michael T. Lua,b,
- Thomas Mayrhofera,b,
- Stefan B. Puchnera,b,
- Ting Liua,b,
- Pal Maurovich-Horvata,b,
- Alexander Ivanova,b,
- Elizabeth Adamia,b,
- Brian Ghoshhajraa,b,
- Souma Senguptaa,b,
- Campbell Rogersa,b and
- Udo Hoffmanna,b
Background: Non-invasive fractional flow reserve (FFR CT) derived from coronary computed tomography angiography (CTA) correlates with invasive FFR. Recent observations showed association of high risk plaque (HRP) with abnormal FFR in stable chest pain patients. We analyzed FFR CT in patients with acute chest pain evaluated in the emergency department and examined the association of HRP with FFR CT measurements.
Methods: We performed core lab analysis of CTA and FFR CT in patients from the ROMICAT II trial who had either >50% stenosis or underwent secondary non-invasive test. FFR CT was analyzed per patient and per vessel (abnormal ≤0.8). The presence of HRP was analyzed by qualitative (positive remodeling, low CT attenuation plaque, napkin ring sign, spotty calcium) and quantitative (plaque volume <30HU, remodeling index) analysis. Acute coronary syndrome (ACS) during index hospitalization was adjudicated by an independent clinical events committee.
Results: Among 116 eligible patients, 68 patients (mean age 55.8±8.4 years, 71% men) had image quality permitting FFR CT analysis. In a per vessel analysis, we found good correlation between stenosis and FFR CT (FFR CT ≤0.8 vs >0.8: 18% vs 82%, 76% vs 24%, 95% vs 5% for stenosis <50%, 50-69%, and ≥70%, respectively, p<0.001). Vessels with FFR CT ≤0.8 had higher prevalence of HRP (any HRP 68% vs 30%, positive remodeling 32% vs 5%, low CT attenuation plaque 23% vs 3%, napkin ring sign 18% vs. 1%, spotty calcium 58% vs. 29%, p<0.001 for all), higher remodeling index (1.24±0.29 vs 1.05±0.14, p<0.001) and plaque volume <30 HU (5±8 mm3 vs 1±5 mm3, p<0.001). Similar results were seen in per patient analysis. In multivariate multilevel mixed-effects logistic regression, the association between HRP and FFR CT ≤0.8 (OR 3.9, 95%CI 1.6-9.9, p=0.007) was independent of stenosis severity. The addition of FFR CT and HRP to stenosis improved discriminatory capacity for ACS as compared to stenosis only (AUC: 0.87, 95%CI 0.79-0.95 vs 0.77, 95%CI 0.67-0.86; p=0.003).
Conclusions: In patients with acute chest pain, abnormal FFR CT is associated with the presence of HRP features independently of stenosis. The addition of FFR CT and HRP to stenosis improves the detection of ACS.
Room 140 B
Sunday, March 19, 2017, 8:25 a.m.-8:35 a.m.
Session Title: Highlighted Original Research: Non Invasive Imaging and the Year in Review
Abstract Category: 27. Non Invasive Imaging: CT/Multimodality, Angiography, and Non-CT Angiography
Presentation Number: 909-06
- 2017 American College of Cardiology Foundation