Adrenal venous sampling in primary aldosteronism: low dilution of adrenal venous blood is crucial for a correct interpretation of the results
Abstract
In primary aldosteronism, adrenal venous sampling (AVS) is essential for subtype differentiation as it evaluates aldosterone secretion from both adrenals. Selectivity of adrenal sampling is assessed by the ratio of cortisol concentrations in adrenal venous blood and inferior vena cava blood.
Since the criteria for selective adrenal sampling differ among the reported literature, we performed a study to evaluate the influence of different selectivity criteria on AVS results. AVS reports of 87 patients were enrolled.
A total of 225 adrenal samples were analysed and divided into five groups according to Cadrenal/Civc:1.1?1.99, 2?2.99, 3?4.99, 5?9.99 and 10. By comparing reference with analysed samples, a concordant assessment with respect to lateralisation of aldosterone secretion was observed in 39, 52, 72, 85 and 94% of the respective groups of analysed samples.
AVS provides consistent information when adrenal samples with high cortisol concentrations are used.