Repeat Adrenal Vein Sampling in Aldosteronism: Reproducibility and Interpretation of Persistently Discordant Results.

CONTEXT: The reproducibility of adrenal vein sampling (AVS) is unknown. OBJECTIVE: This work aimed to determine reproducibility of biochemical results and diagnostic lateralization in patients undergoing repeat AVS. METHODS: A retrospective chart review was conducted of single-center, single-operator AVS procedures at a tertiary care center. Included were patients with confirmed primary aldosteronism (PA) undergoing repeat AVS because of concerns about technical success or discordant diagnostic results. Simultaneous AVS was performed by an experienced operator using a consistent protocol of precosyntropin and postcosyntropin infusion. Among successfully catheterized adrenal veins (selectivity index ≥ 2), the correlation of the adrenalaldosterone/cortisol (A/C) ratio was measured between the first and second AVS. The secondary outcome measure was diagnostic agreement on repeat AVS lateralization (lateralization index ≥ 3). RESULTS: There were 46 sets of AVS from 23 patients at a median of 3 months apart. There was moderate correlation in A/C ratios in the adrenal veins and inferior vena cava (Spearman r = 0.49-0.59, P < .05) pre cosyntropin. Post cosyntropin, the correlation was better (Spearman r = 0.67-0.76, P < .05). In technically successful AVS, there was moderate correlation between the repeated lateralization indices (Spearman r = 0.53, P < .05). In 15 patients in whom repeat AVS was performed because of apparent lateralization discordance with computed tomography imaging, the final diagnosis was the same in the second AVS procedure. Initial failed AVS was successful 75% of the time on repeat attempt. CONCLUSION: Repeat AVS was feasible and usually successful when an initial attempt failed. There was modest correlation between individual repeat adrenal A/C ratios and lateralization indices when AVS was performed twice. The final lateralization diagnosis was identical in all cases. This demonstrates that AVS is a reliable and reproducible localizing test in PA.