Prognostic implications of coronary CT angiography-derived quantitative markers for the prediction of major adverse cardiac events.

OBJECTIVE: To evaluate quantitative markers derived from coronary CT angiography (coronary CTA) for the prediction of major adverse cardiac events (MACE).

MATERIALS AND METHODS: Pooled data from two centers in the US and Europe were retrospectively analyzed. Forty-six patients (65.5 ± 8.1 years, 62% male) with suspected coronary artery disease (CAD) who had undergone dual-source CCTA and had experienced MACE within 12 months were included and compared to a Framingham risk score matched cohort (n = 46) without MACE. Various quantitative markers derived from coronary CTA were compared between both groups: Total plaque volume (TPV), calcified and non-calcified plaque volumes (CPV and NCPV), plaque burden (%), remodeling index, lesion length, presence of Napkin-ring sign, segment involvement score (SIS), and segment stenosis score (SSS). Discriminatory power of these markers for predicting MACE was assessed.

RESULTS: Patients with MACE had significantly more obstructive CAD with higher plaque burden, SSS, and SIS (all p < 0.05) compared to controls. MACE-related lesions showed higher median TPV (122.6 mm(3) vs. 76.3 mm(3)), NCPV (67.3 mm(3) vs. 56.1 mm(3)), plaque burden (66.3% vs. 44.9%), greater lesion length (23.1 mm vs. 19.2 mm), and higher prevalence of Napkin-ring sign (63% vs. 32%) (all p < 0.05). On multivariable analysis, odds ratios (OR) for MACE on a per-patient level were 1.07 for plaque burden (p = 0.0002) and 1.13 for SSS (p = 0.049). On a per-lesion basis OR for lesion length was 1.05 (p = 0.042), 1.03 for plaque burden (p = 0.018), 1.28 for remodeling index (p = 0.026), and 1.68 for the Napkin-ring sign (p = 0.031). At receiver operating characteristics analysis a combination of markers (Framingham risk score + Napkin-ring sign + lesion length + remodeling index) showed the highest predictive value for MACE (AUC 0.92, p = 0.013).

CONCLUSION: Coronary CTA-derived markers portend predictive value for MACE on a per-patient (plaque burden and SSS) and per-lesion level (lesion length, plaque burden, remodeling index, and Napkin-ring sign). A combination of markers added to the Framingham risk score has the highest predictive power.