Impact of endovascular treatment of atherosclerotic renal artery stenosis on endothelial function and arterial blood pressure.

Abstract

Renovascular disease may cause arterial hypertension and decreases renal function, which both impair endothelial function. Endothelial function, a surrogate marker for cardiovascular risk, can be assessed non-invasively by ultrasound. The aim of this study was to investigate the impact of percutaneous transluminal renal artery angioplasty (PTRA) with stenting on endothelial function and arterial blood pressure in patients with renal artery stenosis (RAS). Flow mediated dilatation of the brachial artery, flow velocities and shear stress were measured with high resolution ultrasound in 24 hypertensive patients with renal artery stenosis prior and one day after revascularization by PTRA with stenting. Endothelial-independent brachial dilatation was measured after application of nitroglycerin. Endothelial-dependent dilatation improved from 2.4±0.9% to 6.1±1.4% (P=0.03), whereas endothelial-independent dilatation did not change after PTRA. Endothelial-dependent reactive hyperemic blood flow increased from 195±40 mL/min to 536±94 mL/min (P=0.0008), whereas endothelial-independent hyperemia did not increase after revascularization. After PTRA, shear stress at rest decreased from 37±11 to 23±3 dyne/cm² (P<0.0001), and reactive hyperemic shear stress increased from 89±29 to 107±12 dyne/cm² (P=0.014). The impact of PTRA on arterial blood pressure resulted in a mean decrease of 21±5 mmHg in systolic pressure (P<0.0001), of 9±2 mmHg in diastolic pressure (P=0.03), and of 14±5 mmHg in peripheral pulse pressure (P=0.0003), respectively. Endovascular treatment of renovascular disease improves endothelial function and decreases in resting shear stress.