The comparison of plasma cystatin C levels between the patients with normal coronary angiography and the forms of coronary artery disease in clinics

10.SUMMARY THE COMPARISON OF PLASMA CYSTATIN C LEVELS BETWEEN THE PATIENTS WITH NORMAL CORONARY ANGIOGRAPHY AND THE FORMS OF CORONARY ARTERY DISEASE SEEN IN CLINICS. Introduction and Aim Cystatin C is a powerful inhibitor of cathepsin type proteolytic enzymes which degrades elastin and collagen. It is supposed that the lack of cystatin C in atherosclerotic plaques leads to tearing of plaque capsule and development of clinical cardiovascular disease by excess proteolytic activity. In our study we planned to investigate the plasma cystatin C levels of stable angina pectoris patients without plaque complications and of acute coronary syndrome patients in whom plaque complication is the main pathophysiologic process and to compare them with levels of patients who have normal coronary arteriogram. Material and Method We enrolled patients who admitted to our clinic and undergone coronary angiography between January-2005 and April-2006. The patient are divided in to four groups. Group 1 is the patients with acute myocardial infarction, Group 2 is the ones with unstable angina pectoris and Group 3 is the ones with stable angina pectoris. The cases with normal coronary arteriogram form the Group 4 as control group. Plasma samples was driven in the first 24 hours from the patients with acute myocardial infarction, and in the day of coronary arteriography from the other patients. Plasma cystatin C measurements was done according the nephelometry procedure with the Dade Behring autoanalyser. Findings We enrolled 397 patients to our study. There were no difference between mean ages and body mass indexes of groups. The number of female patients were statistically more in the control group than other groups (p=0,003). There were no difference of plasma cystatin C levels between groups (median values for group 1, group 2, group 3, and group 4 as units of mg/L respectively are 0,95, 0,95, 0,93 and 0,89; p=0,49) Result In our study, plasma cystatin C levels were similar in the patients with and without coronary artery disease and in the clinical subgroup of coronary artery disease. We thought that this is because of the production of local cystatin C levels in atherosclerotic plaque doesn't effect the plasma cystatin C levels. 42