Optimizing adrenal vein sampling interpretation for primary aldosteronism subtyping.

Abstract

Context: Guidelines recommend adrenal vein sampling (AVS) for subtyping primary aldosteronism (PA); however, the optimal sample for determining lateralization when multiple successful adrenal vein samples are obtained is unclear.

Objective: To compare the impact of different adrenal vein sample-selection strategies on PA subtyping.

Methods: A retrospective study was conducted in PA patients who underwent bilaterally successful AVS with multiple samples obtained from each adrenal vein. LI was calculated using four different sample-selection strategies: (1) Maximum Aldosterone (Max Aldo), the sample with the highest aldosterone concentration; (2) Maximum Cortisol (Max Cort), the sample with the highest cortisol concentration; (3) Maximum ACR (Max ACR), the sample with the highest aldosterone-to-cortisol ratio (ACR) across samples; (4) Mean ACR, the average ACR of all samples. The theoretical detection rate of unilateral PA (UPA) and diagnostic accuracy for PA subtyping were compared among the four strategies.

Results: A total of 585 patients with PA were included. In the 460 PA patients who underwent non-adrenocorticotropic hormone (ACTH)-stimulated AVS, the theoretical detection rate of UPA varied significantly among the four sample-selection strategies (P < 0.001), and was highest with Max Aldo (62.0%, 285/460), followed by Max ACR (59.1%, 272/460), Max Cort (57.8%, 266/460) and Mean ACR (56.3%, 259/460). Among 206 patients with postoperative diagnoses, the accuracy also differed significantly among the four strategies (P < 0.001), and Max Aldo ranked first (85.9%, 95% CI: 80.6%-90.1%), followed by Max ACR (84.0%, 95% CI: 78.4%-88.5%), Mean ACR (82.0%, 95% CI: 76.3%-86.8%), and Max Cort (78.2%, 95% CI: 72.0%-83.4%). Max Aldo was more accurate than Max Cort (adjusted P < 0.001), whereas no significant differences were observed between Max Aldo and Max ACR or Mean ACR (all adjusted P > 0.05). In the 308 patients who underwent ACTH-stimulated AVS, Max Aldo yielded the highest numerical detection rate and diagnostic accuracy; however, no significant differences were observed among the four strategies (P = 0.078 for theoretical UPA detection and P = 0.098 for diagnostic accuracy).

Conclusion: For AVS with multiple samples, calculation of the LI based on the sample with the highest aldosterone concentration on each side tended to yield the highest numerical theoretical detection rate of UPA and accuracy, particularly in non-ACTH-stimulated AVS protocols.