Adrenal vein epinephrine levels: a useful aid in venous sampling for primary aldosteronism.

We evaluated the usefulness of adrenal vein epinephrine levels as an indicator of adrenal venous dilution in seven patients with primary aldosteronism who had venous sampling. In six patients adrenal vein epinephrine levels greater than 1500 pg/mL confirmed that relatively undiluted adrenal efflux had been obtained. In another patient a low value of left adrenal vein epinephrine indicated that the sample was markedly diluted with nonadrenal blood. Measurement of epinephrine levels appears to be a useful tool for verifying successful venous sampling, particularly when cortisol and aldosterone levels from the same adrenal vein are not elevated or when deep adrenal vein cannulation cannot be confirmed radiologically.