Abstract 402: Surgical Treatment Of Aldosterone Producing Adenoma Could Change Renovascular Hemodynamics –Decrement Of Resistive Index Evaluated By Renal Doppler Sonography–

Abstract

Patients with untreated primary aldosteronism (PA) often show albuminuria, which is a predictor for the decrement of their eGFR after specific treatment. Although the appropriate treatment of PA patients results in reducing albuminuria, the mechanism is still unclear. We planned a prospective study to investigate the effects of aldosterone on renal hemodynamics. Renal Doppler sonography (RDS) is recognized as non-invasive device to evaluate renal hemodynamics. Renal resistive index (RI), which is calculated by peak-systolic (PSV) and end-diastolic (EDV) flow velocities (RI = (PSV - EDV) / PSV) measured by RDS, has been reported as a surrogate marker for renal function and tissue injury. Ninety four patients with aldosterone producing adenoma (APA) were participated; all of those fulfilled diagnostic criteria of PA and underwent adrenalectomy based on results of adrenal venous sampling. RDS was performed at baseline and followed at 1 and 12 months after adrenalectomy. Ninety one patients with essential hypertension were participated in this study as a control. All sonographic parameters were obtained at bilateral renal arteries including main tract, portal, segmental and interlobular parts and expressed as mean. Aldosterone, blood pressure (BP), albuminuria and estimated glomerular filtration rate (eGFR) were followed throughout the study period. Chronic kidney disease (CKD) was defined as eGFR<60 ml/min/1.73m2 or albuminuria≧30 mg/g creatinine. Initial RI in the patients with untreated APA at all compartment arteries were significantly higher than those in control subjects (0.70 v.s 0.67 at main tract, 0.67 v.s 0.64 at portal part, 0.64 v.s 0.60 at segmental part and 0.63 v.s 0.60 at interlobular part). With significant decrease in aldosterone (from 28.7 to 8.8ng/dl), albuminuria and eGFR significantly declined after adrenalectomy. RI also immediately showed significant declines to 0.67 at main tract, to 0.63 at portal part, to 0.61 at segmental part and to 0.60 at interlobular part, respectively, at 1 month and remained stable through the follow-up period. Furthermore, RI significantly decreased in the APA patients with or without CKD. Surgical treatment of APA could change renovascular hemodynamics according to the decrease of aldosterone.