Objective: Adrenal vein sampling (AVS) is the gold standard investigation for primary hyperaldosteronism. By differentiating unilateral versus bilateral hyperaldosteronism, AVS can influence the decision for surgical or medical treatment. However, AVS yield depends upon successful cannulation of both adrenal veins, which is technically challenging (1). Adrenocorticotropic hormone (ACTH) stimulation has been reported to improve bilateral adrenal vein cannulation rates (2). The aim of this study was to investigate the influence of ACTH stimulation on AVS studies performed at a single tertiary metropolitan hospital.
Method: AVS studies were performed in 43 individuals between 1999 and 2018 by 11 proceduralists. 17 procedures were performed with ACTH stimulation. Successful cannulation was defined as a selectivity index (SI) (adrenal vein:peripheral vein cortisol) greater than 2 pre-ACTH and greater than 3 post-ACTH. Lateralisation was defined as a lateralisation index (LI) (ipsilateral aldosterone/cortisol:contralateral aldosterone/cortisol) greater than 4. An experienced proceduralist was defined as having performed more than the median number of AVS procedures.
Results: 43 procedures were conducted and the median number performed per proceduralist was 1. 15 procedures achieved bilateral adrenal vein cannulation. Unsuccessful right adrenal vein cannulation occurred in 23 patients. 17 of the total and 12 of the successful procedures were performed with ACTH stimulation; the rate of bilateral adrenal vein cannulation improved from 3 of 26 without stimulation to 12 of 17 with stimulation. Post-stimulation cannulation was significantly more successful than pre-stimulation (p = 0.001). 9 of 15 successful procedures were performed by the most experienced proceduralist, 7 of which were performed with stimulation; however, there was no association between above median experience and successful cannulation (p = 0.40).
Conclusion: Successful bilateral adrenal vein cannulation improved with ACTH stimulation. In future, point-of-care cortisol and Cone Beam CT to image the adrenal veins may further assist bilateral cannulation rates (3).