Serum Endothelin-1, MMP-9, and Myeloperoxidase and Coronary Artery Morphology as Detected by Multi-Slice CT Angiography in Intermediate and High Risk Asymptomatic Subjects

To study possible correlation between Endothelin-1, Matrix-metallo-proteinase- 9, and Myeloperoxidase serum activity and coronary CT angiography findings of atherosclerotic coronary artery disease in intermediate - high risk asymptomatic subjects.

65 consecutive asymptomatic subjects, 53 males and 12 females, mean age 58.8 +/-10.9 s.d., referred by their primary practitioner for the evaluation of coronary artery atherosclerotic disease by Cardiac CT exam were selected for the study. One serum sample was drawn from each participant and examined for the levels of Endothelin -1, MMP-9, MPO serum activity. Obstructive coronary artery disease was defined as at least 50 percent stenosis of one or more coronary segments. Plaques were identified as calcified or soft according to the CT Hounsfield attenuation number.

The Endothelin activity level was significantly elevated in subjects with significant obstructive coronary artery disease (p=0.022). Furthermore, high Endothelin activity level was found to correlate with calcified plaque burden (p=0.006), and to be an independent determinant of lesion severity (R² = 0.124, R² change = 0.006, p= 0.008)

Endothelin-1 may be a marker of significant obstructive coronary disease and calcified plaque burden in asymptomatic subjects. The significance of MMP-9 and MPO as markers of atherosclerosis in such subjects has not been definitely clarified.