Evaluation of stable coronary artery disease by multiple cardiac biomarkers

ABSTRACT

Effective management of stable coronary artery disease [SCAD] relies on early detection of coronary atherosclerosis. The objective was to evaluate diagnostic accuracy and risk stratification of SCAD patients by high sensitivity C reactive protein [hs CRP], Myeloperoxidase [MPO] and Pregnancy Associated Plasma Protein-A [PAPP-A]. validation study was conducted at Pathology Department of the Army Medical College, in collaboration with Armed Forces Institute of Cardiology [AFIC/NIHD] Rawalpindi. Total 122 subjects consisting of 61 patients of SCAD and 61 angio-negative controls were included. The levels of biomarkers were measured before angiography by using kits provided by Siemens [UK] for hs CRP and Abbott for MPO on Immulite 1000 and Architect Analyzer respectively, whereas serum PAPP-A was measured by an ELISA based method using kit provided by IBL Germany. The mean age of the patients was 56.57 +/- 8.35 years and consisted of 53 [86.9%] males and 8 [13%] females. Area under curve [AUC] and 95% CI of hs CRP 0.817 [0.736-.881] was significantly higher than that of MPO 0.685 [0.594-0.766] [p=0.018] and PAPP-A 0.565 [0.472-0.655] [p<0.001] for the diagnosis of SCAD. Patients in the highest quartile of PAPP-A were at the highest risk for adverse events as PAPP-A had the highest Hazard Ratio [HR] of 3.4 [p=0.004], as compared to hs CRP 1.124 [p=0.191] and MPO 0.998 [p=0.176]. hs CRP has superior diagnostic ability for detection of SCAD than MPO whereas PAPP-A is a more reliable marker for risk stratification among the cardiac biomarkers