Relationship between endothelial dysfunction and coronary risk factors and coronary artery desease?s extend and severity

Introduction and Objectives: Coronary artery disease (CAD) became the most common cause of death in western societies and endothelial dysfunction is supposed to be associated with CAD and cardiovascular risk factors. The goal of our study was to evaluate the relation between CAD risk factors and endothelial dysfunction in patients with or without any angiographically defined CAD and to show the association between endothelial dysfunction and, presence ,extend and severity of CAD.Materials and Method: 80 patients with CAD including 28 female patients (mean age 62.4±9.9 years) were recruited to the study group and 20 patients with normal coronary arteries including 14 female patients (mean age 57.6±10.5 years) to the control group. Patients with an history of coronary angioplasty or coronary artery by-pass surgery were excluded. Endothelial dysfunction was evaluated by assessing endothelium-dependent vasodilatory response (EDVR) and nitrate-dependent vasodilatory response (NDVR) with ultrasonography of brachial artery.Extend and severity of CAD was determined upon number of diseased vessels and Gensini score.Results: Diabetic patients had significantly lower EDVR and NDVR values in CAD(+) group (p=0.037 and p=0.035,respectively), whereas patients above 65 years of age had a significantly lower NDVR value in CAD (-) group (p=0.05). Neither group provided a significant relationship between other risk factors and EDVR and/or NDVR values. EDVR and NDVR were also found to be significantly lower in CAD (+) group compared to that of CAD(-) group. (p=0.0001). A strong correlation was found out between number of diseased vessels and EDVR, NDVR and Gensini score (r=-0.560, r= -0.522, r=0.601, respectivelyp=0.0001). In the CAD (+) group, single-vessel and multi-vessel diseases could be distinguished by measuring EDVR with a cut-off level of 8.5 % (sensitivity : 95%, specificity: 62%) and NDVR with a cut-off level of 13.6 % (sensitivity : 91%, specificity: 62%). In addition, CAD(+) group presented a strong correlation between Gensini score and EDVR or NDVR (r=-0.825, r=-0.778 respectively, p=0.0001).Conclusion: In the current study we detected a clear association between age and diabetes as CAD risk factors and endothelial dysfunction. We also realized that defects in endothelial function was more frequent in CAD (+) group and degree of endothelial dysfunction correlates well with the extend and severity of CAD. Based on data of our study, we suggest that evaluation of endothelial dysfunction with a non-invasive ultrasonographic method may be useful in diagnosis and prediction of CAD severity and extend.