Successful lateralization by adrenal vein sampling in a patient of primary aldosteronism on concurrent mineralocorticoid receptor antagonist: Time to change the narrative

Introduction

Primary aldosteronism (PA) is the most common endocrine cause of hypertension. Untreated PA carries a high cardiovascular morbidity and mortality. Subtyping with adrenal venous sampling (AVS) is essential for tailoring the therapeutic management. Mineralocorticoid receptor antagonists (MRA) are recommended to be discontinued prior to AVS but it entails a risk of worsening of hypertension and occurrence of hypokalemia. Literature is sparse regarding successful subtyping with AVS without discontinuing MRA. We report a case of PA highlighting successful subtyping with AVS followed by a positive response to adrenalectomy without discontinuing MRA (in a dose of >200 mg/day).

Case report

A 50 year old gentleman, known case of PA was requiring six classes of antihypertensive drugs, including 300 mg Eplerenone. In view of age >35 years and bilateral adrenal masses, he was planned for subtyping with AVS. It was deemed difficult to stop MRA prior to AVS. Renin levels were low, despite taking MRA, which indicated incomplete mineralocorticoid receptor blockade. AVS was done on concurrent MRA usage which indicated lateralization of excess aldosterone production to the right side. Patient underwent robot assisted right adrenalectomy. Post-surgery, there was a partial clinical success and complete biochemical success.

Conclusion

In patients with severe PA, hypertension and/or hypokalemia might be difficult to control without MRA. Successful lateralization with AVS can be done in patients with suppressed renin levels, even on MRA treatment.