Time of Day and Its Effect on Adrenal Vein Sampling

Monday, March 31, 2025

4:03 PM – 4:12 PM CT

Location: Music City Center, 202 BC

Presenting Author(s)

Scott M. Pierce, MD

PGY-3 IR/DR
Oregon Health & Science University, United States

Author/Co-author(s)

Brian Park, MD, MS

Assistant Professor
Oregon Health & Science University, United States
KQ

Keith Quencer, MD (he/him/his)

Associate Professor of Interventional Radiology, School of Medicine; Section Chief of IR Body
Oregon Health and Science University, United States

Purpose: To assess effect of diurnal variation in cortisol levels on selectivity index for unstimulated adrenal vein sampling.

Materials and Methods: Forty-six patients had AVS performed with pre and post cosyntropin stimulation between April 2022 and June 2024. All cases had diagnostic post-stimulated sampling using a selectivity index (SI) > 3.0. Sequential sampling of the right adrenal vein, left adrenal vein, and infrarenal IVC is performed first without any synthetic ACTH. Then, 250 µg of cosyntropin is given by IV bolus and repeat sampling is done 15 minutes later. Angiography confirmed consistent catheter positioning both pre and post cosyntropin stimulation. Samples were divided into AM and PM groups and compared using student’s t-test and chi-squared test. Pre-stimulation absolute cortisol levels and selectively indices (SI) were compared. SI >2.0 was used as threshold for adequacy for pre-stimulation sampling.

Results: There was no difference in the unstimulated diagnostic adequacy (average AM SI = 4.46 vs average PM SI = 6.81, p = .14) or in the unstimulated IVC cortisol levels (average AM IVC cortisol = 11.8 vs average PM IVC cortisol = 7.2, p = .15) between the AM and PM groups, respectively. Of the 46 tests, 26 unstimulated samples did not achieve diagnostic adequacy. There was no significant difference between the diagnostic adequacy in the morning and the afternoon (14 AM tests vs 12 PM tests) X2 (1, N = 46) = 1.41, p = .24.

Conclusion: There was no significant difference in sampling adequacy for unstimulated AVS performed in the morning or the afternoon. Despite the diurnal cycle of cortisol, our study showed that both morning and afternoon times are acceptable for adequate adrenal vein sampling.