Super-Selective Adrenal Venous Sampling: A Diagnostic Tool when Planned, but a Liability when Incidental

Adrenal vein sampling (AVS) is considered the gold standard for differentiating unilateral from bilateral primary hyperaldosteronism. However, anatomical variations in adrenal venous drainage can complicate interpretation. We report the case of a 55-year-old female referred for evaluation of primary hyperaldosteronism and resistant hypertension who underwent technically successful AVS, yet with inconclusive results, warranting a repeat AVS. During the repeat procedure, an unusual venous variant was identified: a right superior and inferior adrenal vein. Recognition of this variant was essential to avoid misinterpretation of results. This case highlights the importance of understanding venous anatomy during AVS and the need for meticulous venographic evaluation when unexpected findings are encountered.