Unilateral Adrenalectomy for Primary Aldosteronism Due to Bilateral Adrenal Disease Can Result in Resolution of Hypokalemia and Amelioration of Hypertension.

BACKGROUND: Bilateral idiopathic hyperaldosteronism (IHA) is responsible for 60% of primary aldosteronism (PA) cases. Medical management is standard of care for IHA. Unilateral adrenalectomy (UA) with the intent of debulking total aldosterone production as a palliative measure remains controversial.
METHODS: Single-center retrospective review (2010-2020) of patients undergoing UA with a diagnosis of PA due to IHA (lateralization index [LI] on adrenal venous sampling [AVS] < 4). Demographic, pre-operative, intra-operative, and post-operative variables were assessed. Hypertensive regimens were converted to the WHO Defined Daily Dose (DDD).
RESULTS: Twenty-four patients were identified, 14, 58% male and mean age 52 ± 10 years. Preoperative hypokalemia was present in 22, 92% of patients. Median number of antihypertensives taken was 3 (interquartile range [IQR], 2-4) and median DDD was 4 (IQR, 3-5.3). Median lateralization index on AVS was 3.52 (range, 1.19-3.88). All operations were performed in minimally invasive fashion. There were no conversions to open procedure, ICU admissions, or post-operative complications. Median follow-up was 10.5 months (range, 1-145 months). Hypokalemia resolved in 17, 76% of patients at last follow-up. Post-operative median number of antihypertensives taken was 1 (IQR, 1-3) and median DDD was 2 (IQR, 0.5-2.75) from 4, P = 0.003. Three (%) patients required continuation of mineralocorticoid receptor antagonists post-operatively. Blood pressure control improved in 65% of patients.
CONCLUSION: Unilateral adrenalectomy in the setting of bilateral hyperaldosteronism can improve blood pressure control and stabilize potassium levels in selected patients. Further prospective studies in larger cohorts will be necessary to further define the role of unilateral adrenalectomy in the setting of PA due to bilateral adrenal disease.