Abstract 269: Coronary Artery Calcium As A Predictor For Stenting Outcomes: A Meta-analytic Comparison

Abstract

Coronary Artery Calcium (CAC) measurement and its usefulness to stratify patients by CAD risk remains an area of controversy. Current AHA/ACC guidelines recommend using CAC to guide management on patients with risk factors for CAD but not on optimal medical treatment. The purpose of this study is to investigate the impact of CAC on stenting outcomes. Methods: A systematic review of MEDLINE using PRISMA guidelines was conducted using the search terms CAC, Calcium, Coronary, and Stent. Studies were included if they had an appropriate control group and subdivided high coronary calcium and low coronary calcium measured using an approved imaging modality. Clinical characteristics of patients and outcomes were aggregated according to the Cochrane Manual. A random effects model was used to retrieve odds ratio values. Revman 5.3 was used to aggregate outcomes. Results: A total of 11 studies with 56,725 patients were included. The high CAC cohort included 14,390 patients and Low/No CAC included 42,335 patients. TLR was significantly higher in the high CAC cohort: Odds Ratio: 1.82 [1.37, 2.43], Test for overall effect: Z = 4.08 (P < 0.0001). Heterogeneity was significant amongst the studies for TLR but not amongst TVR or Stent Thrombosis outcomes (Heterogeneity: Tau 2 = 0.14; Chi 2 = 84.08, df = 10 (P < 0.00001); I 2 = 88%). TVR and Stent Thrombosis was significantly higher in the high CAC cohort: Odds Ratio 1.20 [1.14, 1.26] and Odds Ratio 1.42 [1.24, 1.62] Test for overall effect: Z = 5.01 (P < 0.00001) respectively. Conclusion: TLR, TVR, and Stent Thrombosis were all significantly higher in the high CAC cohort as compared to control. Elevated CAC not only provides a description of coronary plaque morphology but also can be used to predict adverse interventional outcomes. Further prospective studies with standard imaging techniques are needed to eliminate any inter-imaging modality differences in CAC characterization.