Plasma metanephrine for assessing the selectivity of adrenal venous sampling

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 53-73-Primary Aldosteronism & Mineralocorticoid Excess
Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-60
Jacques W.M. Lenders*1, Tanja Dekkers1, Jaap Deinum1, Leo J. Schultze Kool1, Dirk Blondin2, Oliver Vonend3, Ad R.M.M. Hermus4, Mirko Peitzsch5, Lars Rump2, Gerald Antoch2, Fred CG J Sweep1, Stefan Richard Bornstein5, Holger Willenberg3 and Graeme Eisenhofer5
1Radboud University Nijmegen Medical Center, Nijmegen, Netherlands, 2University Hospital Duesseldorf, Dusseldorf, Germany, 3University Hospital Duesseldorf, Duesseldorf, Germany, 4Radboud University Nijmegen Medical Centre, Nijmegen, 5University Hospital Carl Gustav Carus, Dresden, Germany
Context: More reliable parameters than cortisol are needed for assessing correct catheter positioning during adrenal vein sampling (AVS). Plasma metanephrine represents one such alternative.

Objective: To determine the utility of adrenal venous (AV) plasma concentrations of metanephrine to establish correct catheter positioning during AVS.

Design and methods: We included 86 AVS procedures: 52 ACTH-stimulated and 34 non-stimulated sequential procedures. Plasma cortisol, metanephrine, normetanephrine, epinephrine and norepinephrine concentrations were measured in AV and peripheral venous (PV) samples. AVS success rates, according to cortisol AV:PV selectivity indices of 2.0 and 3.0, were compared with that for metanephrine using a selectivity index (SI) determined by ROC curve analysis.

Results:Among AVS procedures assessed as selective using a cortisol SI of 3.0, the median AV:PV plasma metanephrine ratio was 6-fold higher than that for cortisol (94.0 versus 15.5, P<0.0001). There were significant positive relationships between AV-PV ratios for cortisol and metanephrine for ACTH-stimulated samplings, but not for non-stimulated samplings. ROC curve analysis indicated a plasma metanephrine SI cut-off of 10. There was 96% concordance in AVS success rates determined by cortisol (SI=3.0) and metanephrine (SI=10) in ACTH-stimulated AVS. Without stimulation, the concordance was 82% and 59% at respective cortisol-derived SIs of 2.0 and 3.0; AVS success rates determined by metanephrine (91%) were higher (P<0.01) than those determined by cortisol at an SI of 3.0 (56%), but not 2.0 (79%).

Conclusions: Metanephrine provides an alternative analyte to cortisol for sensitive assessment of AVS selectivity that appears particularly advantageous in sampling performed without ACTH stimulation.

Nothing to Disclose: JWML, TD, JD, LJS, DB, OV, ARMMH, MP, LR, GA, FCJS, SRB, HW, GE

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm