Impact of different diagnostic criteria during adrenal vein sampling on reproducibility of subtype diagnosis in patients with primary aldosteronism

In patients with primary aldosteronism (PA), adrenal vein sampling (AVS) is considered the only reliable technique to distinguish between unilateral and bilateral autonomous production of aldosterone, but agreement is lacking on the best criteria indicating successful cannulation and lateralisation. The objective of this study was to assess the impact of differing criteria for successful cannulation and lateralization on reproducibility of subtype diagnosis. Sixty two patients with confirmed PA underwent AVS on two separate occasions, because the first was unsatisfactory. We compared the different diagnoses of PA subtype reached using AVS data assessed by permissive (type 1), intermediate (type 2) and strict (type 3) criteria. Although 91.1% of all (both first and second) AVS were “successful” by type 1 criteria (50.8% by type 2 and 33.9% by type 3), in only 32.2% of patients was the diagnosis concordant between first and second AVS. Type 1 criteria also led to a higher rate of diagnosis of unilateral PA (67.3% of “successful” procedures) than type 2 (36.5%) or type 3 (26.2%). There was considerable disparity in the diagnosis reached using the three different criteria, with concordance in only 32.2%. Using either type 1 or 2 criteria, the minimal adrenal/peripheral vein cortisol ratio necessary to obtain the same diagnosis in the first and second AVS procedures was ≥ 2.75. In conclusion, permissive criteria for successful cannulation and lateralisation on AVS achieve poor diagnostic reproducibility and should be avoided.