Adrenal vein sampling.

Adrenal vein sampling is the gold standard for localizing aldosterone-secreting adenomas and for distinguishing adenomas from bilateral adrenal hyperplasia in patients with primary hyperaldosteronism. The importance of this distinction cannot be overstated because the former is curable surgically, whereas the latter is managed medically. Primary hyperaldosteronism has historically been underdiagnosed as a cause of hypertension, but recent reports highlight its ubiquitous nature with a prevalence of 5%-10% in screened hypertensive patients. Of such patients, up to 62.5% have a potentially curable adenoma as the underlying etiology. Adrenal vein sampling is a safe, highly effective procedure that is shown to alter the clinical management in 35.7% of primary hyperaldosteronism patients who would have otherwise been treated improperly based on the results of CT or other modalities. Although adrenal vein sampling is hindered by the inherent difficulty of catheterizing the right adrenal vein, technical success is reported as high as 97% in experienced hands. In this article, we review aldosterone physiology and the clinical workup of primary aldosteronism as well as the anatomic, technical, and analytical factors to be considered with adrenal vein sampling.