Inquiring about the link between urotensin-II and coronary collateral development in coronary artery patients with and without diabetes

Aims: Coronary collateral circulation consists of vascular channels activated to maintain perfusion in major epicardial coronary arteries in severe stenosis or occlusion. Yet, coronary collateral development (CCD) in diabetic patients was previously proven to be poor. Urotesin-II (U-II) is famous for being the most potent vasoconstrictor agent, and plasma levels are known to elevate in diabetic patients and play an important role in diabetic complications. In this study, we inquired about the link between U-II levels and the development of coronary collaterals between diabetic and non-diabetic patients with coronary artery disease (CAD). Methods: We recruited 31 diabetic and 30 non-diabetic patients with 95% or more coronary artery stenosis or occlusion and considered Rentrop’s classification for grading collaterals. In this sense, while Rentrop grades 0-1 are regarded as poor CCD, Rentrop grades 2-3 correspond to well-developed collaterals. Moreover, we compared the patients’ serum levels of U-II by the degree of CCD. Results: The findings revealed that demographic characteristics did not significantly differ between the groups (p >0.05). Although CCD seemed worse in diabetic patients than those without diabetes (DM), the finding was not statistically significant. However, the diabetic patients had significantly higher U-II levels than non-diabetic patients (388.1±314.2 vs. 229.8±216.9, p=0.026). Despite not being significant, U-II levels were higher in patients with poor CCD than those with well-developed collaterals in the non-diabetic group (370.6±298; 178.6±158.3, p=0.2). In the diabetic group, on the other hand, U-II levels were significantly higher in patients with poor CCD and significantly lower in patients with good CCD (582.7±316.4 and 180.4±121.6, respectively; p