Adrenal Venous Sampling in Patients With Positive Screening but Negative Confirmatory Testing for Primary Aldosteronism

Abstract

Adrenal venous sampling is considered to be the most reliable diagnostic procedure to lateralize aldosterone excess in primary aldosteronism (PA). However, normative criteria have not been established partially because of a lack of data in non-PA hypertensive patients. The aim of the study was to investigate aldosterone concentration and its gradient in the adrenal vein of non-PA hypertensive patients. We retrospectively studied the results of cosyntropin-stimulated adrenal venous sampling in 40 hypertensive patients who showed positive screening testing but negative results in 2 confirmatory tests/captopril challenge test and saline infusion test. Plasma aldosterone concentration, aldosterone/cortisol ratio, its higher/lower ratio (lateralization index) in the adrenal vein with cosyntropin stimulation were measured. Median plasma aldosterone concentration in the adrenal vein was 25 819 pg/mL (range, 5154–69 920) in the higher side and 12 953 (range, 1866–36 190) pg/mL in the lower side ( P <0.001). There was a significant gradient in aldosterone/cortisol ratio between the higher and the lower sides (27.2 [5.4–66.0] versus 17.3 [4.0–59.0] pg/mL per μg/dL; P <0.001) with lateralization index ranging from 1.01 to 3.87. The aldosterone lateralization gradient was between 1 to 2 in 32 patients and 2 to 4 in 8 patients. None of the patients showed lateralization index ≥4. The present study demonstrated that plasma aldosterone concentration in the adrenal veins showed significant variation and lateralization gradient even in non-PA hypertensive patients. Adrenal venous sampling aldosterone lateralization gradients between 2 and 4 should be interpreted with caution in patients with PA because these gradients can be found even in patients with negative confirmatory testing for PA.

Correlation Between Lateralization Index of Adrenal Venous Sampling and Standardized Outcome in Primary Aldosteronism

“…We also found that younger patients achieved a good biochemical outcome more frequently than did older patients ( P < 0.01) (data not shown); however, on AVS finding, contralateral aldosterone suppression was not associated with surgical benefits in terms of clinical and biochemical outcomes (data not shown). Additionally, we have reported that LI between 2 and 4 can be found even in patients with negative confirmatory testing for PA [ 21 ]. Therefore, clinicians could send patients in these LI zones to surgery with careful consideration for patient characteristics.…”

Subtype Diagnosis of Primary Aldosteronism: Is Adrenal Vein Sampling Always Necessary?

“…In a recent informative study, AVS performed in patients with a positive screening test for PA but a negative confirmatory testing, demonstrated that eight out of 40 patients had an LI comprised between two and four, and no patients showed an LI greater than 4 suggesting that 2 ≤ LI ≤ 4 should be cautiously interpreted [70]. …”

Treatment of Unilateral PA by Adrenalectomy: Potential Reasons for Incomplete Biochemical Cure

“…The importance of using stringent LI was later highlighted by a study investigating LI from patients with hypertension with PA excluded. Lateralization gradients between 2 and 4 were found in 20 % of patients with negative confirmatory test for PA, with LIs ranging from 1.01 to 3.87 [69].…”