dromlakhani Determine when adrenal venous sampling is indicated for PA subtyping
STEP 1 — Gather Information
Confirm PA diagnosis via positive screening (ARR ≥200 and PAC ≥60 pg/mL) and at least one confirmatory test; assess surgical feasibility (patient desire for adrenalectomy, age, comorbidities, surgical risk); note typical PA findings: age <35 years, spontaneous hypokalemia (K⁺ <3.5 mEq/L), PAC >300 pg/mL, unilateral adrenal tumor on CT.
STEP 2 — Rule In / Rule Out
Is surgical treatment feasible and desired by the patient? If no, AVS is not indicated for subtyping; if yes, proceed to subtyping evaluation.
STEP 3 — Classify or Stratify
Does the patient have typical PA findings (age <35, spontaneous hypokalemia, PAC >300 pg/mL, unilateral adrenal tumor on CT)? If yes, consider bypassing AVS after informed consent; if no, proceed to AVS for definitive subtyping.
STEP 4 — Decide
Recommend AVS for functional subtyping unless typical PA findings are present and the patient/physician agree to forego AVS after discussing risks, benefits, and alternatives.
Clinical Guardrails / Mimics / Pitfalls
Do not perform AVS in patients with uncontrolled coagulopathy, severe contrast allergy, or inability to lie flat; do not rely solely on CT/MRI for subtype diagnosis; avoid bypassing AVS in elderly patients or those with atypical findings without thorough discussion of diagnostic uncertainty; ensure ACTH stimulation per protocol to improve catheterization success.
Concrete Clinical Example
A 48‑year‑old man with confirmed PA (ARR 250, PAC 110 pg/mL, positive saline suppression test), normokalemia, bilateral adrenal nodules on CT, desires adrenalectomy; typical PA findings absent → proceed to AVS, which shows lateralization index >4 with ACTH, guiding unilateral adrenalectomy.
Source: Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021, Japan Endocrine Society, 2021, https://doi.org/10.1007/s00223-021-00845-9 (representative DOI)