Abstract 13836: Accessory Renal Arteries Perfuse a Substantial Fraction of Renal Mass: Studies in Renal Denervation Patients
Introduction: Renal denervation is an emerging therapy for resistant hypertension, but has a non-response rate of roughly 15-30%. Untreated accessory renal arteries may have a potentially causative role in non-response. Prior data show a strongly proportional relationship between individual renal mass and cross sectional area of the principal artery perfusing that kidney, analogous to the relations between myocardial mass and coronary artery area. Because accessory renal arteries are prevalent (up to 65%) in patients undergoing renal denervation, we questioned whether accounting for their presence would further strengthen the correlation between renal mass and artery cross sectional area.
Methods: High resolution CT scans from 34 participants in the REDUCE-HTN Clinical study were measured for kidney volume and main renal artery area (TRAA). Areas of all visible accessory arteries were measured separately. Standard linear regression was used to determine the quantitative relationship among these parameters.
Results: Total renal volume and TRAA did not differ between left and right kidneys. A strong relationship was found between TRAA and kidney volume, (R=0.726 p=0.0075). Assuming a renal tissue density of 1.0 g/cm3, each square mm of renal artery lumen perfuses on average 15.8 grams of renal parenchyma. Accessory renal arteries were found in 62% of these kidneys. Correlation with renal mass was significantly stronger when total accessory artery cross sectional area was included in the correlations. Accessory artery area comprised 8% and 10%, respectively, of total renal artery area in right and left kidneys.
Conclusions: Accessory renal arteries appear to perfuse roughly 10% of renal mass if blood flow is proportional to artery area. Since incremental renal mass is strongly proportional to accessory artery area, and since accessory renal arteries frequently contain sympathetic axons (based on anatomic studies), presence of these vessels may have implications for renal denervation strategies in patients with multiple renal arteries. If non-response to renal denervation is due in part to accessory renal arteries (and the sympathetic nerves they supply), clinical strategy should include treating accessory vessels.
Author Disclosures: T. Houghland: None. J.J. Hamann: None. N.T. Nemoto: None. R.F. Garberich: None. K. Rosenthal: None. J.R. Lesser: None. R.S. Schwartz: None.
- © 2014 by American Heart Association, Inc.