title: Does contralateral suppression at adrenal venous sampling predict outcome following unilateral adrenalectomy for primary aldosteronism? A retrospective study.
abstract: BACKGROUND
  In primary aldosteronism (PA), adrenal vein sampling (AVS) distinguishes unilateral and bilateral disease by comparison of aldosterone/cortisol (A/F) ratios. There is controversy about the criteria for interpretation, however, and in particular it is not clear whether contralateral suppression (CS) (defined as A/F(adrenal) ≤ A/F(peripheral) on the unaffected side) is important. We therefore performed a retrospective study to determine whether CS in surgically treated unilateral PA was associated with blood pressure (BP) and biochemical outcomes.
  
  
  METHODS
  Patients who underwent unilateral adrenalectomy for PA after successful AVS were included if the lateralization index (A/F(dominant):A/F(nondominant)) was ≥ 2. Cases were reviewed at 6 to 24 months follow-up for outcomes with respect to the presence and degree of CS.
  
  
  RESULTS
  Sixty-six of 80 patients had CS. Baseline characteristics were similar. At postoperative follow-up, those with CS had lower systolic BP (SBP) (128 mm Hg vs 144 mm Hg, P = .001), a greater proportion with cure or improvement of hypertension (96% vs 64%, P = .0034), a greater proportion with biochemical cure of PA on fludrocortisone suppression testing (43 of 49 [88%] vs 4 of 9 [44%], P = .002) and were taking a lower median number of antihypertensive medications (0 vs 1.5, P = .0032). In a multivariate model, the degree of CS and preoperative SBP were both significantly correlated with postoperative SBP, but the lateralization index, sex, and age were not.
  
  
  CONCLUSIONS
  In this study, the presence of CS correlated with good BP and biochemical outcomes from surgery. This finding suggests that CS should be a factor in deciding whether to offer surgery for treatment of PA.
authors: Endocrine Hypertension Research Centre, University of Queensland School of Medicine, Greenslopes and Princess Alexandra Hospitals, Brisbane 4102, Australia.
authors: Martin J
authors: MJ
authors: Wolley
authors: Richard D
authors: RD
authors: Gordon
authors: Ashraf H
authors: AH
authors: Ahmed
authors: Michael
authors: M
authors: Stowasser
mesh_terms: D000293:Adolescent; D000311:Adrenal Glands / Q000098:blood supply; D000315:Adrenalectomy; D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000097:blood*; D001800:Blood Specimen Collection; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D006929:Hyperaldosteronism / Q000097:blood* / Q000175:diagnosis* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000450:Aldosterone; D006854:Hydrocortisone