Role for adrenal venous sampling in primary aldosteronism

The aim of this study was to determine the effect of adrenal venous sampling (AVS) on the management of patients with primary aldosteronism.

From September 1990 through October 2003, 203 patients with primary aldosteronism (mean age, 53 years; range, 17-80; 163 men) were selected prospectively for AVS on the basis of degree of aldosterone excess, age, desire for surgical treatment, and computed tomographic (CT) findings.

Both adrenal veins were catheterized in 194 patients (95.6%). Notable among the 110 patients (56.7%) with unilateral aldosterone hypersecretion were 24 (41.4%) of 58 patients with normal adrenal CT findings, 24 (51.1%) of 47 with unilateral micronodule (< or =10 mm) apparent on CT (7 had unilateral aldosterone hypersecretion from the contralateral adrenal), 21 (65.6%) of 32 with unilateral macronodule (>10 mm) apparent on CT (1 had unilateral aldosterone hypersecretion from the contralateral adrenal), 16 (48.5%) of 33 with bilateral micronodules, and 2 (33%) of 6 with bilateral macronodules.

On the basis of CT findings alone, 42 patients (21.7%) would have been incorrectly excluded as candidates for adrenalectomy, and 48 (24.7%) might have had unnecessary or inappropriate adrenalectomy. AVS is an essential diagnostic step in most patients to distinguish between unilateral and bilateral adrenal aldosterone hypersecretion.