Catheterization During Adrenal Vein Sampling for Primary Aldosteronism: Failure to Use (1–24) ACTH May Increase Apparent Failure Rate

“Successful” adrenal vein catheterization in p rimary a ldosteronism ( PA ) is often defined by a ratio of >3:1 of cortisol in the adrenal vein vs the inferior vena cava . Non‐use of corticotropin ( ACTH) during sampling may increase the apparent failure rate of adrenal vein catheterization due to lower cortisol levels. A retrospective study was performed on all patients with confirmed unilateral PA between J une 2005 and A ugust 2011. Adrenal vein sampling ( AVS) included simultaneous bilateral baseline samples with repeat sampling 15 minutes after intravenous infusion of 250 μg of C ortrosyn ( ACTH ‐ S ). Successful catheter placement was judged as adrenal cortisol: IVC cortisol of >3:1, applied to both baseline and ACTH ‐ S samples and lateralization of aldosteronism was judged as normalized aldosterone/cortisol ( A / C ) ratio >3 times the contralateral A / C ratio. In ACTH ‐ S samples, 94% of right‐sided catheterizations were biochemically successful with 100% success on the left. Among baseline samples, only 47% of right‐ and 44% of left‐sided samples met the 3:1 cortisol criteria. However, 95% of apparent “failed” baseline cortisol sets still showed lateralization of A / C ratios that matched the ultimate pathology. Non– ACTH ‐stimulated samples may be incorrectly judged as failed catheter placement when a 3:1 ratio is used. ACTH ‐stimulated sampling is the preferred means to confirm catheterization during AVS .