Association between invasive central and peripheral blood pressure and endothelial function in patients with stable coronary artery disease

Background
Endothelial function is an independent predictor of coronary artery disease and is regulated by a number of factors, including blood pressure. However, the definitive relationship between endothelial function and invasive central and peripheral blood pressure has not been described in patients with stable coronary artery disease (CAD).

Methods
In patient with CAD (diameter stenosis ≥30%), invasive central (aortic) and left peripheral (brachial) blood pressures were determined during transradial coronary angiography. The endothelial function was evaluated by way of flow-mediated dilatation (FMD) of the brachial artery.

Results
We enrolled 413 consecutive patients. There were 260 patients with significant CAD (sCAD, diameter stenosis ≥ 50%) and 153 patients with non-significant CAD (nsCAD, diameter stenosis <50% and ≤ 30%). FMD was significantly and inversely correlated with central and peripheral parameters in terms of systolic blood pressure, mean arterial pressure, and pulse pressure (PP) (r=-0.332, r=-0.184, and r=-0.407, respectively, all p<0.001) and (r=-0.303, r=-0.190, and r=-0.319, respectively, all p<0.001). Compared with sCAD, there was closer correlation between central PP with FMD in nsCAD (r=-0.548 vs. r=-0.345, both p<0.001). After adjusting potential confounders such as age, body mass index and high-sensitivity C-reactive protein, multivariate analysis showed that FMD remained independently associated with central PP, degree of coronary artery stenosis, and brachial-ankle pulse wave velocity in all patients. In patients with nsCAD, the multivariate analysis showed that only central PP was independently correlated with FMD.

Conclusions
In patients with stable CAD, a decline in endothelial function is most closely associated with invasive central pulse pressure.