Endocrine Abstracts

Background: Given the technically challenging nature of adrenal venous sampling (AVS) there is a drive to centralise services to improve successful outcomes. This has potential implications for patients living in remote and rural areas.

Methods: We retrospectively reviewed the case notes of 15 patients who underwent AVS in our hospital, for investigation of primary hyperaldosteronism between 2002 and 2015. We assessed the success rate of cannulation of the right adrenal vein (i.e., an adrenal:peripheral vein cortisol ratio >3.0 in basal state and >5.0 following ACTH stimulation) and evaluated whether the care provided is in accordance with the guidelines of the Endocrine Society 2008.

Results: Two radiologists performed a total of 19 AVS in 15 patients, with three individuals undergoing repeat procedures. The mean age at time of AVS was 50±11 years, with 10 (67%) males and 5 (37%) females. 11 (73%) patients had been referred to the Endocrine Clinic from primary care and 4 (27%) via the renal clinic. All patients had a raised aldosterone:renin ratio, but only 7 (47%) underwent confirmatory testing with a saline suppression test. This increased to 75% after 2008. Morphology of the adrenal glands was normal on CT in 10 (67%) patients, whilst lesions were identified in the right adrenal gland in 3 (20%), and the left adrenal gland in 2 (13%) cases (nodule mean size 15.4 mm). Cannulation of the right adrenal vein was successful in 73% of procedures and localised the diagnosis to a unilateral adenoma in 33%, while 67% of patients were diagnosed with bilateral hyperplasia. All patients with unilateral adenomas underwent adrenalectomy. Cannulation of the left adrenal vein was successful in 14 (94%) cases.

Discussion: Despite the relatively low numbers of patients, the rate of successful cannulation of the right adrenal vein was reassuring and compares favourably to national data, with a success rate of 63%. Arguably better success rates could be achieved if services were centralised and national success rates improved. However, the additional travel time (potentially 3–6 h drive one way) has implications for our clinic population.