CRP, IL-6 and endothelin-1 levels in patients undergoing coronary artery bypass grafting. Do preoperative inflammatory parameters predict early graft occlusion and late cardiovascular events?

BACKGROUND: Inflammation is a major contributor to atherosclerotic vascular disease. Inflammatory parameters such as C-reactive protein (CRP) and Interleukin-6 (IL-6) have been shown to be strong predictors of cardiovascular events. The association between preoperative inflammatory parameters and early graft occlusion as well as cardiovascular events after coronary artery bypass grafting (CABG) has not, however, been fully elucidated. The aims of the present study were to prospectively investigate the prognostic value of the inflammatory parameters IL-6, CRP, and endothelin (ET-1) to predict early graft occlusion as well as late cardiovascular events after CABG. METHODS: In the present study 99 patients undergoing CABG because of stable angina pectoris due to significant coronary artery disease were prospectively included. Coronary angiography was repeated 3 months after CABG in 81 patients in order to evaluate early graft occlusion. Blood samples were collected before CABG in all patients. Patients were followed up for a median of 5 (3-7) years after CABG. RESULTS: Twenty-five patients (31%) had one or more occluded grafts at the 3-month control coronary angiography. The patients with occluded grafts had higher preoperative CRP and IL-6 levels in plasma [CRP 2.22 (1.11-4.47) mg/L vs. 1.23 (0.71-2.27) mg/L P=0.03] and [IL-6 2.88 (1.91-5.94) pg/mL vs. 2.15 (1.54-3.14) pg/mL P=0.006]. There were 23 late cardiovascular events among the 99 patients during the follow-up. Patients experiencing late cardiovascular events had higher preoperative IL-6 levels than those without late cardiovascular events [4.13 (1.83-5.87) pg/mL vs. 2.08 (1.53-2.29) pg/mL, P=0.002] whereas CRP levels did not differ significantly between the two groups [1.5 (0.79-4.41) mg/L vs. 1.33 (0.74-2.48) mg/L, P=0.41]. Looking at IL-6, a cut off value more than 3.8 pg/ml was associated with a significant higher risk for an early graft occlusion (P=0.04) and late cardiovascular events (P=0.00003). Preoperative endothelin-1 did not predict early graft occlusions or late cardiovascular events. CONCLUSIONS: Raised preoperative IL-6 levels are predictors of both early graft occlusion and late cardiovascular events after CABG. Elevated preoperative CRP levels can predict early graft occlusion after CABG. Endothelin did not differ between the two groups.

Carotid atherosclerosis is correlated with extent and severity of coronary artery disease evaluated by myocardial perfusion scintigraphy.

Increased intima-media thickness (IMT) in the common carotid artery (CCA) correlates with conventional risk factors for cardiovascular disease and is an independent predictor of cardiac events. However, correlation between IMT and degree of ischemic heart disease evaluated by coronary angiogram is weak. The purpose of this study was to investigate the relationship between measures of carotid atherosclerosis and the extent and severity of coronary artery disease (CAD) in 111 consecutive patients (60 men and 51 women, mean age 60 years) with known or suspected CAD who were investigated with adenosine-stress myocardial perfusion scintigraphy. Common carotid artery lumen diameter (LD) and IMT of the carotid bulb and distal CCA were measured with ultrasound, and CCA cross-sectional intima-media area (CIMA) was calculated. Seventy-two of 110 patients (65%) had significant perfusion defects. Increasing carotid plaque occurrence (absence, unilateral or bilateral occurrence) correlated with more advanced CAD (p<0.01). The extent and severity of myocardial hypoperfusion correlated significantly with presence of carotid plaque (r=0.23 and 0.24 respectively, p<0.05), CIMA (r=0.23 and 0.22, p<0.05), and LD (r<0.26 and 0.25, p<0.01) but not with IMT. In contrast to CIMA, LD failed to show an independent relation to extent of CAD after adjustment for age, sex, and body mass index. In conclusion, in subjects with intermediate to high risk of ischemic heart disease, occurrence of carotid plaques and increased cross-sectional intimamedia area in the common carotid artery are the best parameters for predicting CAD expressed as myocardial hypoperfusion.