Endocrine Abstracts

Introduction: Primary aldosteronism is an important cause of hypertension. Adrenal venous sampling (AVS) is the gold-standard investigation to determine whether one or both adrenal glands are affected. AVS is a complicated procedure with success rate varying greatly from one hospital to another.

Aims: To investigate the success rate of AVS at Landspitali over a 10-year period and compare it to published results from other hospitals.

Methods: The results from all AVS procedures performed from 2007 throughout 2016 in Landspitali National University Hospital of Iceland were retrospectively reviewed. Landspitali is a tertiary referral center for the whole country. We collected data on serum concentrations of aldosterone and cortisol from both adrenal veins, inferior vena cava and a peripheral vein. All patients were started on synacthen (tetracosactrin) infusion of 93,75 μg/h at least one hour before the AVS. Selectivity index (SI) for each side was calculated by dividing the serum concentration of cortisol from the appropriate adrenal vein by the serum cortisol concentration from a peripheral vein. An AVS was considered successful if serum concentrations of cortisol were five times greater in the adrenal veins than in the peripheral vein, e.g. SI>5 on both sides.

Results: During the 10-year period, 66 AVS procedures were performed at Landspitali. A total of 57 were successful, which gives a success rate of 86%. Six (9%) AVS procedures gave SI<5 on the right side only and two (3%) gave SI<5 on the left side only. One (2%) AVS gave SI<5 bilaterally. Seven (11%) AVS procedures were repeated due to difficulties cannulating the right adrenal vein. All seven repetitions were successful.

Conclusions: Despite being a small nation, the success rate of AVS at Landspitali, Iceland, is fairly good (86%). The success rate is not far from published numbers from Gothenburg, Sweden, (92%) and Mayo Clinic, Rochester, USA, (96%). All the AVS procedures at Landspitali were performed by the same specialist throughout the study period, which is considered to be the key to this success.