Discordant imaging: adrenal vein sampling in almost half of patients with primary aldosteronism and a unilateral adrenal adenoma.

BACKGROUND: Primary hyperaldosteronism (PHA) is an underdiagnosed cause of secondary hypertension, with an increased risk of cardiovascular and renal complications compared with those with essential hypertension alone. Distinguishing between unilateral and bilateral aldosterone secretion is important as management differs. Adrenal vein sampling (AVS) is the gold standard for determining lateralisation. Current international guidelines suggest AVS may be omitted in those aged <35 years with PHA and a unilateral adrenal adenoma on imaging. AIM: To characterise all patients referred for AVS at Waitemata District Health Board (WDHB), review the success rate of AVS and compare concordance of AVS with imaging. METHODS: All patients who underwent AVS in WDHB from January 2015 to September 2020 were retrospectively assessed. Clinical records, laboratory data and radiological findings were reviewed. RESULTS: Ninety-six patients underwent AVS, with four excluded as private records were unable to be obtained. Of the 92 patients included, age ranged from 22 to 79 years. AVS was successful on first attempt in 89 (96.7%) patients. AVS and imaging findings were concordant in 62.2% of patients. One (14.3%) of seven aged <35 years had discordant results, and 16 (47%) of 34 patients with a unilateral adenoma on imaging had discordant results to AVS. CONCLUSIONS: AVS at WDHB is successful on first attempt in most patients. AVS is essential in the management of PHA for those deemed to be surgical candidates, regardless of age.