AORTIC STIFFNESS AND AORTIC TO ARTERIAL MISMATCH AS MARKERS OF KIDNEY INJURY IN HYPERTENSION

Abstract

Objective: Vascular stiffening is an important feature of the cardiorenal syndrome. Which hemodynamic and vascular parameters that are of most importance, and thereby best might serve as predictive markers for kidney failure in a hypertensive population, remains unclear. We therefore investigated a broad spectrum of hemodynamic parameters in a hypertensive population with kidney function ranging from normal to severe dysfunction, and then studied their independent relation to eGFR. Methods: Individuals with hypertension and varying degree of kidney dysfunction from two RCTs (DoRa and SOLID) were studied. Carotid to femoral (CF) pulse wav velocity (PWV), carotid to radial PWV, aortic (CF) to arterial (CR) mismatch (CF/CRPWV ratio), flow mediated vasodilation (FMD), subendocardial viability ratio (SEVR), central pulse pressure, central blood pressure, and echocardiographic measures of stiffness (left atrial volume index, E/é, left ventricular mass index) were measured. Hemodynamic parameters were correlated to kidney function, and for significant correlations, independence was investigated with multivariate regression. Design and method: 107 participants were investigated, with eGFR ranging from 130 to 21 ml/min, mean eGFR of 73.8 ml/min. Mean age was 58 years, 9.3% had experienced a cardiovascular event, and 30.8% were on antihypertensive treatment. Mean BP was 150/87mmHg. CFPWV, a measure of aortic stiffness, and CF/CRPWV, a measure of the mismatch between aortic and arterial stiffness, showed independent correlations with eGFR (−coeff −0,159, p = 0.01 and −coeff −0.123, p = 0.04 respectively), whereas neither measures of endothelial dysfunction nor measures of ventricular stiffness showed significant correlations. Conclusion: Our results imply a profound importance of aortic stiffness in chronic kidney disease related vascular dysfunction, and suggest that measures of aortic PWV and the mismatch to arterial PWV might serve as risk markers of kidney injury in the hypertensive population.