Determine need for adrenal venous sampling in addition to CT for PA lateralization
STEP 1 — Gather Information
Confirm primary aldosteronism diagnosis via elevated ARR, assess surgical candidacy and desire for adrenalectomy, review CT adrenal morphology (size, laterality), note patient age, presence of hypokalemia, and exclude familial hyperaldosteronism syndromes.
STEP 2 — Rule In / Rule Out
Is the patient a surgical candidate who desires adrenalectomy?
- No → recommend medical therapy; stop.
- Yes → proceed to classify CT findings.
STEP 3 — Classify or Stratify
Evaluate CT for unilateral adenoma >1 cm in patients <35 years with marked PA and hypokalemia.
- If all present → high probability lateralizing PA; AVS may be unnecessary.
- Otherwise → AVS indicated.
STEP 4 — Decide
If AVS unnecessary → proceed with CT‑guided surgical planning.
If AVS indicated → perform CT with adrenal venous sampling prior to deciding medical vs surgical treatment.
Clinical Guardrails / Mimics / Pitfalls
Relying on CT alone can misclassify bilateral disease or nonfunctioning adenomas; AVS requires experienced interventional radiologist and adequate cortisol/aldosterone assays; avoid AVS in familial hyperaldosteronism types I‑IV, bilateral macronodular hyperplasia, or uncontrolled hypertension; ensure renin suppressed and potassium normal before AVS to prevent false‑lateralization.
Concrete Clinical Example
A 32‑year‑old woman with hypertension, spontaneous hypokalemia, ARR 45, CT shows 1.3 cm left adrenal adenoma, desires surgery, no family history. Age <35, marked PA, hypokalemia, >1 cm adenoma → AVS may be omitted; she undergoes left laparoscopic adrenalectomy and is cured.
Source: Primary Aldosteronism: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2025, https://doi.org/10.1210/clinem/dgaf284
TODO: consider adding scripts/calc.py for the endo-pa-lateralization-imaging calculator