Endothelial function in patients with chest pain and normal coronary angiograms

A normal coronary angiogram is found in about 20% of patients who undergo coronary angiography due to chest pain. In some of them syndrome X is diagnosed. Endothelial dysfunction is one possible cause of this pathology.

To compare the endothelial function estimated by two different methods in patients with typical or atypical anginal pain and with no chest pain.

Fifty-three patients who underwent coronary angiography due to suspected coronary artery disease and who had a normal coronary angiogram were included in the study: 34 patients had typical anginal pain (group 1) and 19 patients had atypical chest pain (group 2). The control group consisted with 20 subjects without chest pain. The plasma concentration of such endothelial markers as von Willebrand factor (vWF), thrombomodulin (TM), endothelin 1 (ET-1), tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1) and C-reactive protein were measured. We also determined endothelial-dependent brachial arterial dilatation (flow-mediated dilation, FMD).

The groups of patients were different with regard to the factors of known effects on endothelial function but endothelial markers were not different in all groups with two exceptions. The concentration of tPA was the highest in patients with typical chest pain and the concentration of PAI-1 was the highest in patients without chest pain. The FMD values were low in all patients and there were no significant differences in the FMD values between the three analysed groups. We did not find any correlation between the concentration of examined endothelial markers and FMD. A non-significant relationship between the presence of classical risk factors and decreased FMP was observed. We have found a significant relationship between the number of risk factors and FMD, tPA, PAI-1 and hsCRP.

The assessment of endothelial function using FMD or estimation of endothelial markers is not useful to differentiate chest pain.