Abstract 5807: First Demonstration that Coronary CT Angiography Reveals Coronary Arterial Vessel Wall Thickening in Patients with Intermediate and High Framingham Risk Score
Introduction. Early atherosclerosis is characterized by vessel-wall thickening with preserved lumen size. Contrast-enhanced coronary artery computed tomography (CTA) has been validated for stenosis detection and characterization of atherosclerotic plaques but vessel wall thickening in patients with high Framingham risk score (FRS) has not been shown. We hypothesized that increased mean percent vessel wall area (PVWA) and remodeling index (RI) reflect early vessel wall thickening in subjects with higher FRS, with preservation of luminal size.
Methods. We assessed 25 patients with coronary CTA using a validated, highly standardized approach on a commercial post processing workstation (Vitrea; SurePlaque 4.0). FRS was calculated by standard criteria. We evaluated 153 segments in patients with low FRS (<10%) and 35 segments in patients with intermediate-high FRS (>10%). Mean minimal lumen diameter (MLD), minimal lumen area (MLA), remodeling index (RI), and PVWA were compared with unpaired t-test in patients with low versus >10% FRS. Mean PVWA was calculated as follows: (total vessel area-lumen area)/total vessel area. p-value <0.05 was considered significant.
Results. In all patients, mean FRS was 7%; 20 patients had FRS<10% and 5 had FRS>10%. PVWA and RI were significantly higher in the intermediate-high FRS group compared to low FRS (0.46±0.07 vs 0.42±0.07; p=0.04 and 0.97±0.15 vs 0.92±0.13; p=0.004, respectively), while MLD/MLA were similar (Figure 1⇓).
Conclusions. This is the first demonstration that coronary CTA can detect vessel wall thickening with preserved lumen size in patients with FRS>10%.