Abstract 3649: The Metabolic Syndrome and Collateral Circulation in Patients with Occlusive Coronary Artery Disease : A Role for Insuline Resistance, PAI-1 and Adiponectin
The metabolic syndrome(MS) is associated with an increased cardiovascular risk. Patients with the MS have lower adiponectin level and heightened expression of PAI-1. Because previous in vitro and animal studies have demonstrated that adiponectin and PAI-1 can interfere with the angiogenic process, it has been hypothesized that they could modulate collateral circulation in humans. We investigated the relation between the MS and the extent of collateral circulation in patients with occlusive coronary artery disease. 387 consecutive patients with at least one coronary occlusion of a major coronary vessel at diagnostic angiography were prospectively enrolled. Lipid, fasting serum glucose, hs-CRP, fibrinogen, adiponectin, PAI-1 and insulin concentrations were measured at the time of angiography. The duration of coronary occlusion was defined based on clinical and ECG data. Collateral development was graded using a validated angiographic method. The MS was defined according to the ATP-III definition. The MS was associated with less developed collateral vessels, as measured by the mean collateral flow grade (2.22±1.19 vs 2.84±1.04, p<0.0001). Mean collateral flow grade was 2.84±1.12 for patients with low PAI-1 level (≤23 ng/mL) compared to 2.21±1.26 for patients with high PAI-1 level (>23 ng/mL, p=0.0001). Mean collateral flow grade was 2.31±1.33 for patients with low adiponectin level (≤6483 ng/mL) compared to 2.72±1.13 for patients with high adiponectin level (≤6483 ng/mL, p=0.0005). In multivariate analysis adjusting for potential confounding factors including the duration of coronary occlusion; fasting glycaemia (p=0.0007), insulin-resistance (HOMA-IR; p=0.01), hypertension (p=0.008), high circulating PAI-1 concentration (p=0.01), and low adiponectin concentration (p=0.01) were key independent predictors of poor coronary collateral circulation. This study shows that in patients with occlusive coronary artery disease, collateral circulation is impaired in patients with the MS. This effect is related to key variables linked to insulin-resistance. In addition, our results suggest that PAI-1 or adiponectin are reasonable targets to modulate coronary collateral circulation in humans.