Background: In primary hyperaldosteronism (PHA), CT is the sensitive imaging to visualise adrenal adenoma. However, because of the high incidence of adrenal incidentalomas, adrenal venous sampling (AVS) is frequently required to indentify unilateral (UD) or bilateral (BD) disease. AVS can be technically difficult and result can be operator dependant.
Method: We retrospectively reviewed the last 14 cases of AVS performed in our hospital. The criterion of UD was set at 4 folds difference in ratio of Aldosterone to renin level on either adrenal vein.
Results: Mean age was 61year(3879), 5 females. All patients were hypertensive and 13 were hypokalemic on presentation. All had biochemically confirmed PHA with aldosterone (pmol/l) to renin (pmol/ml/min) of >1000. AVS identified 7(50%) UD and 5(35%) BD. Two (7%) had sampling difficulty on approaching right adrenal vein (one had an aberrant and one had a very small veins). Comparing with CT adrenals, there were 6 (43%) concordances (4 UD and 2 BD on AVS) and 6(43%) discordances (3 UD and 3 BD on AVS). Among UD indentified by AVS, 6 underwent unilateral adrenelectomy and 1 was awaiting operation. All patients had positive out come post-operatively i.e., all normokalaemic, 3 cured, 3 required less antihypertensives. All patients achieved blood pressure <135/85 mmHg (≤2 antihypertensives). Histology showed 4 adenoma, 1 hyperplasia and 1 microadenoma. All 8 patients who have not had surgery were on aldosterone agonists (7 on Spironolactone and 1 on epleronone).They required mean 3.5 antihypertensives therapy (range 16). Target BP (140/90 mmHg) was achieved on 6 patients.
Conclusions: In our case series, AVS provided invaluable and reliable information to guide choice of therapy i.e., surgical vs medical. It can be particularly highlighted in 3 positive outcomes with UD where CT adrenals were unable to indentify the tumours. Catheterising right adrenal vein remained challenging in minority of the cases.
Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.