P6153High risk plaque by coronary CTA predict cardiac events but not all-cause mortality: long term follow up

Abstract Background Ultra long-term (10 years) outcome data of coronary computed tomography angiography (CTA) for coronary heart disease (CHD) screening are lacking. Novel CTA imaging biomarkers (“high-risk-plaque”) may improve risk stratification. Aims To define CT-imaging predictors for long–term outcomes. Methods 1430 low-to-intermediate-risk patients (mean age 57.9 years; 44.4% females) were included into our prospective cohort study. Coronary Calcium Score (CCS) and CTA were performed. CTA was evaluated for: Stenosis severity (minimal<25%; mild<50%; moderate 50–70%; severe >70%) (CADRADS 1–4), total mixed plaque burden (G-score), high–risk-plaque criteria: 1) low attenuation plaque 2) Napkin-ring (“lunar-eclipse” sign) 3) spotty calcification 4) remodeling index Primary endpoint was all-cause mortality, secondary endpoints cardiovascular mortality and composite (non-fatal and fatal) MACE. Results Over a follow-up of mean 10.55 years ±1.98 (range, 6.1–12.8), all-cause mortality rate was 106 (7.4%), cardiovascular mortality 25 (1.75%) and composite MACE 57 (4%). In patients with negative CTA, cardiovascular mortality was 0% and composite MACE rate 0.2%. Stenosis severity (CADRADS) was the strongest predictor for all 3 endpoints (p<0.001) on multivariate analysis (unadjusted and adjusted for risk factors, p<0.001) but calcium score >100 AU only predicted mortality on the unadjusted multivariate analysis (p=0.045) but not on the adjusted. On multivariate analysis, G-score (p<0.0001), LAP<60HU and the Napkin-Ring predicted composite MACE (p<0.001) but not all-cause mortality, before and after adjusting for risk factors (p=0.007 and 0.001 for LAP<60HU and Napkin-Ring, respectively) while spotty calcification and remodeling index did not. 465 had calcium score zero and in 156 (33.5%) of those, noncalcified fibroatheroma were found (total rate, 11%), 4.9% had >50% stenosis. However only 1 patient with calcium score zero died while there were 6 MACE. High risk plaque with “lunar eclipse” Conclusions Long-term prognosis is excellent if CTA is negative. Stenosis severity by CTA predicts all-cause and cardiovascular mortality, while calcium score predicts only mortality. Plaque burden and the high-risk plaque criteria LAP<60 and Napkin-Ring (syn. “lunar eclipse”) are strong predictors of MACE, but not all–cause mortality. Coronary CTA outperforms calcium scoring for risk stratification.