title: Adrenal vein sampling: substantial need for technical improvement at regional referral centres.
abstract: OBJECTIVE
  Adrenal vein sampling (AVS) is the gold standard for localization of aldosterone producing adenoma. The anatomy of the right adrenal vein makes this procedure technically demanding and it may yield no clinical information if the adrenal veins are not adequately cannulated. Having frequently observed the technical failure of AVS, we undertook a review of 220 procedures in British Columbia, Canada.
  
  
  METHODS
  Subjects were retrospectively identified through the laboratory information system. The following were collected: demographics, screening aldosterone concentration and renin activity/mass, results of dynamic function tests, AVS aldosterone and cortisol results. Standard calculations were performed on AVS data and site-specific success rates were compared. The effect of adrenocorticotropin hormone (ACTH) stimulation on the selectivity index (SI) and lateralization index (LI) were explored.
  
  
  RESULTS
  The overall technical success-rate of AVS procedures was only 44% in procedures where no ACTH-stimulation was used (n=200) but this rose significantly (p<0.01) to 82% for those employing ACTH (n=139). ACTH-stimulation significantly increased the median SI (left: 5.8 vs 36.7, p<0.01; right: 7.0 vs 51.2, p<0.01), and salvaged 36 procedures from yielding no information, 21 of which demonstrated lateralization of aldosterone production. In 64 cases showing lateralization both pre and post-stimulation, ACTH significantly decreased the median LI from 5.4 to 2.2, p<0.01, creating substantial risk for spurious loss of lateralization.
  
  
  CONCLUSIONS
  The technical success of AVS is lower than reported elsewhere. Provided that effects on the LI are considered, the use of ACTH-stimulation during AVS assists in the identification of unilateral forms of PA.
authors.affiliation: Faculty of Arts and Science, Queen's University, Kingston ON, Canada.
authors.forename: Panda
authors.initials: P
authors.lastname: Elliott
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Holmes
mesh_terms: D000236:Adenoma / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D000310:Adrenal Gland Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D000311:Adrenal Glands / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D000324:Adrenocorticotropic Hormone / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000097:blood; D002170:Canada; D002404:Catheterization / Q000379:methods; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008875:Middle Aged; D012017:Referral and Consultation; D012083:Renin / Q000097:blood; D012189:Retrospective Studies; D013048:Specimen Handling / Q000592:standards*
chemical_list: D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D012083:Renin; D006854:Hydrocortisone
keywords: ACTH; APA; AVS; Adrenal Vein Sampling; Adrenal hypertension; Adrenal vein sampling; Adrenocorticotropin Hormone; Aldosterone Producing Adenoma; BAH; BC; Bilateral Adrenal Hyperplasia; British Columbia; Conn's syndrome; IVC; Inferior Vena Cava; LAV; LI; LL; Lateralization Index; Left Adrenal Vein; LifeLabs; Mineralocorticoid; PA; PRA; PRM; Plasma Renin Activity; Plasma Renin Mass; Primary Aldosteronism; Primary aldosteronism; RAV; Right Adrenal Vein; SAC; SI; SPH; Selectivity Index; Serum Aldosterone Concentration; St. Paul's Hospital