Supplemental Data and Methods: Subtyping of Primary Aldosteronism in the AVIS-2 Study: Assessment of Selectivity and Lateralisation

Context:
Adrenal venous sampling (AVS) is the key test for subtyping primary aldosteronism (PA), but its interpretation varies widely across referral centers and this can adversely affect the management of PA patients.
Objectives:
To investigate in a real life study the rate of bilateral success, identification of unilateral aldosteronism and blood pressure outcomes in PA subtyped by AVS.
Design and settings:
in a retrospective analysis of the largest international registry of individual AVS data (AVIS-2 study) we investigated how different cut-off values of the selectivity (SI) and lateralization index (LI) affected rate of bilateral success, identification of unilateral aldosteronism and blood pressure outcomes.
Results:
AVIS-2 recruited 1625 individual AVS studies performed between 2000 and 2015 in 19 tertiary referral centers. Under unstimulated conditions, the rate of biochemically confirmed bilateral AVS success progressively decreased with increasing SI cut-offs;
furthermore, with currently used LI cut-offs the rate of identified unilateral PA leading to adrenalectomy was as low as < 25%. A within-patient pairwise comparison of 402 AVS performed both under unstimulated and cosyntropin-stimulation conditions
showed that cosyntropin increased the confirmed rate of bilateral selectivity for SI cutoffs ≥ 2.0, but with reduced lateralization rates (p < 0.001). Post-adrenalectomy outcomes were not improved by use of cosyntropin or more restrictive diagnostic criteria.
Conclusion:
Commonly used SI and LI cut-offs are associated with disappointingly low rates of biochemically defined AVS success and identified unilateral PA. Evidence-based protocols entailing less restrictive interpretative cut-offs might optimize the clinical use
of this costly and invasive test.

背景：
肾上腺静脉采血（Adrenal venous sampling, AVS）是原发性醛固酮增多症（primary aldosteronism, PA）亚型分类的关键检测手段，但不同转诊中心对其结果的解读差异显著，这可能对PA患者的管理产生不利影响。
目的：
在真实世界研究中，探讨经AVS亚型分类的PA患者的双侧成功（采血）率、单侧醛固酮增多症的识别率及血压结局。
设计与场景：
本研究对最大规模的国际个体AVS数据注册库（AVIS-2研究）进行回顾性分析，探讨选择性指数（selectivity index, SI）和偏侧指数（lateralization index, LI）的不同截断值如何影响双侧成功（采血）率、单侧醛固酮增多症的识别率及血压结局。
结果：
AVIS-2研究纳入了2000年至2015年间在19家三级转诊中心完成的1625例个体AVS检测数据。在未刺激条件下，经生化确认的双侧AVS成功（采血）率随SI截断值升高而逐渐降低；此外，使用当前常用的LI截断值时，经识别并接受肾上腺切除术的单侧PA患者比例低至<25%。对402例同时接受未刺激和促肾上腺皮质激素（cosyntropin）刺激条件下AVS检测的患者进行配对比较发现，促肾上腺皮质激素可提高SI截断值≥2.0时的双侧选择性确认率，但偏侧率降低（p<0.001）。使用促肾上腺皮质激素或更严格的诊断标准并未改善肾上腺切除术后的结局。
结论：
常用的SI和LI截断值与生化定义的AVS成功（采血）率及单侧PA识别率低得令人失望相关。采用限制性较低的解读截断值的循证方案或可优化这一昂贵且有创检测的临床应用。