The role of radiologic studies in the evaluation and management of primary hyperaldosteronism.

BACKGROUND

Surgical treatment of primary hyperaldosteronism (PHA) requires demonstration of unilateral adrenal hypersecretion. Optimal methods for interpretation of imaging and invasive testing are still in development.

METHODS

A retrospective review from 1996-2007 of 106 patients with PHA was undertaken. Patient demographics, biochemical studies, radiologic imaging, operative reports, and pathology were reviewed and comparisons made. Optimal ratios for adrenal vein sampling were tested with regard to sensitivity and specificity. Preoperative and postoperative medication requirements and blood pressures were compared among different treatment groups.

RESULTS

Seventy-eight patients (62 surgically treated) met criteria for inclusion. Median arterial blood pressure at diagnosis was 150/86 mm Hg while taking 3 antihypertensive medications. 69.2% required potassium supplementation. Median aldosterone:renin ratio was 107.0. Forty-two AVS procedures changed the management of 15 patients (35.7%) when compared to CT results. AVS accuracy was 96.6 vs 88.9% for NP-59 scintigraphy. Operative patients remained on fewer antihypertensive medications (1 vs 3), and mean systolic pressure was lower (130 vs 146 mm Hg) compared with medically managed patients.

CONCLUSION

When used together, pre-ACTH aldosterone ratios, normalized A/C:A/C ratios, ratios to define contralateral suppression, and post-ACTH stimulated values allowed for capture of episodically secreting tumors and subtle unilateral or bilateral hyperaldosteronism.