Adrenal venous sampling in primary hyperaldosteronism: comparison of radiographic with biochemical success and the clinical decision-making with "less than ideal" testing.

BACKGROUND: Adrenal venous sampling (AVS) is used in the workup of primary hyperaldosteronism (PA). The purpose of this study was to determine the success rate of AVS and to examine the decision-making process after "less than ideal" AVS.
METHODS: A total of 60 patients underwent 62 AVS for PA. Biochemical evidence of adrenal vein cannulization was analyzed with adrenal-peripheral cortisol ratios. Pathology and clinical outcomes were reviewed in patients undergoing adrenalectomy.
RESULTS: Bilateral cannulization was confirmed in only 21% (pre-adrenocorticotropic hormone [ACTH] infusion) and 44% (post-ACTH infusion) AVS. Of 39 patients who underwent adrenalectomy for presumed unilateral disease, only 16 patients had "ideal" AVS, and 18 patients had only unilateral cannulization on AVS. Despite this, 11 appeared to lateralize and 7 had imaging to support unilateral disease. Postoperatively, 15 (82%) had a significant reduction in their blood pressure, and 7 (39%) of these were cured. Surgery failed in 2 patients; both were found to have bilateral hyperplasia. Bilaterally unsuccessful cannulization (n = 5) still lateralized in 3 patients, and 2 patients had nodules on computed tomography scan. All 5 patients had significant reduction in blood pressure, and 2 were cured.
CONCLUSIONS: ACTH infusion during AVS enhances the biochemical evidence of adrenal vein cannulization. Following "less than ideal" AVS, clinical decisions can still be made using anatomic and partial AVS data.