The reliability of endothelial progenitor cells (CD34 + , KDR+ , and CD34 + /KDR+) in the diagnosis of coronary artery disease and its severity

Background: Bone marrow-derived endothelial progenitor cells (EPCs) play an integral role in the regulation and protection of the endothelium, as well as new vessel formation. Changes in EPC number and function during coronary heart disease allow their use as a biomarker. However, so far, there is no suggested definite level at which we can diagnose coronary artery disease (CAD) or determine the severity of the disease.Aim of the work: To assess the sensitivity, specificity, and accuracy of the circulating EPCs count to diagnose coronary heart disease and to predict the severity of the disease.Patients and methods: The percentage and count of circulating EPCs (CD34+KDR+, CD34+, and KDR+) were measured by flow cytometry in 52 patients who underwent diagnostic angiography. The correlation between the level of the EPCs on the one hand and the presence or absence of CAD and the Gensini score calculated for each patient on the other was determined.Results: Thirty-eight patients were found to have CAD and 14 had normal coronaries. For those with CAD, 22 had single-vessel disease and 16 had multiple vessel disease. It was found that EPCs (CD34+KDR+% and count and CD34+%) were significantly lower in patients with CAD compared with those with normal coronaries. CD34+KDR+% had an AUROC of 0.846 to diagnose CAD, with a sensitivity of 45.5%, a specificity of 100%, a positive predictive value (PPV) of 100%, a negative predictive value (NPV) of 64.3%, and an accuracy of 72.75%. CD34+% and count and CD34+KDR+ count were negatively correlated with the Gensini score. CD34+% has an AUROC of 0.802 to diagnose the Gensini score of more than 6, with a sensitivity of 100%, a specificity of 55.2%, a PPV of 69%, an NPV of 100%, and an accuracy of 77.6%.Conclusion: EPCs decrease in patients with CAD compared with those without CAD. CD34+KDR+% can diagnose CAD with a sensitivity, specificity, PPV, NPV, and accuracy of 45.55, 100, 100, 64.3, and 72.75%. CD34% can help to exclude the presence of severe CAD with a sensitivity, specificity, PPV, NPV, and accuracy of 100, 55.2, 69, 100, and 77.6%, respectively.