Adrenal venous sampling: the learning curve of a single interventionalist with 282 consecutive procedures

PURPOSE:Primary aldosteronism (PA) is a common cause of secondary hypertension. Adrenal venous sampling (AVS) is the gold standard for assessing laterality of PA, which is of paramount importance to decide adequate treatment. AVS is a technically complicated procedure with success rates ranging between 30% and 96%. The aim of this study was to investigate the success rate of AVS over time, performed by a single interventionalist.METHODS:This was a retrospective study based on consecutive AVS procedures performed by a single operator between September 2005 and June 2016. Data on serum concentrations of aldosterone and cortisol from right and left adrenal vein, inferior vena cava, and peripheral vein were collected and selectivity index (SI) calculated. Successful AVS was defined as SI >5.RESULTS:In total, 282 AVS procedures were performed on 269 patients, 168 men (62%) and 101 women (38%), with a mean age of 55±11 years (range, 26–78 years). Out of 282 AVS procedures, 259 were successful, giving an overall success rate of 92%. The most common reason for failure was inability to localize the right adrenal vein (n=16; 76%). The success rates were 63%, 82%, and 94% during the first, second, and third years, respectively. During the last 8 years the success rate was 95%, and on average 27 procedures were performed annually.CONCLUSION:Satisfactory AVS success rate was achieved after approximately 36 procedures and satisfactory success rate was maintained by performing approximately 27 procedures annually. AVS should be limited to few operators that perform sufficiently large number of procedures to achieve, and maintain, satisfactory AVS success rate

Qualitative and quantitative aspects on nitric oxide metabolism. An experimental study in the rat and in man

Background. Nitric oxide (NO) is a biomediator with significant physiological functions in the cardiovascular, nervous, and immune systems. NO is synthesized in the vascular endothelium by enzymatic conversion of L-arginine and O2 to L-citrulline in the presence of NO synthase. Nitrate is the main end-product of NO metabolism. NO plays an important role in a number of disease states. The aim of the present theses was therefore to develop and evaluate methods for assessment of formation of NO, qualitatively as well as quantitatively. Experimental Animals, Subjects and Methods. The study comprised anaesthetized and awake normotensive Wistar rats (WR), young and adult spontaneously hypertensive rats (SHR) and five healthy men. WR were injected s.c. equimolar amounts of 15NO gas or K15NO3. The appearance of 15N-labeled nitrate in plasma was followed for 450 min. In another study, WR were injected i.v. with 15N-L-arginine, and the appearance of 15N-nitrate was followed in plasma, urine, and faeces for up to 7 days. In other two studies, WR and SHR were placed in an air-tight cage and allowed to breathe 18-Oxygen containing mixture for 2 hours. The newly formed 18O-nitrate was measured in plasma with GC/MS, and the total formation of NO was calculated. WR and SHR were also treated with norepinephrine (NE) and adenosine, respectively, and the effects of blood pressure changes on NO formation were evaluated. Finally, healthy men were breathing 18O-containing mixture, and NO formation was estimated. The effect of NO synthase inhibitors (L-NAME and L-NMMA) on NO formation was determined in rats and in men. Results. Out of the subcutaneously administered 15NO gas in rats 89% was detected as 15N-nitrate in plasma. After the administration of 15N-L-arginine, during 7 days no 15N-nitrate was detected in faeces, while high concentrations of 15N-nitrate were measured in plasma and urine. The total formation of NO in young WR was estimated to 0.55±0.04 mmol/kg/h. L-NAME dose-dependently decreased the synthesis of NO. In young SHR the formation of NO was increased to 0.72±0.04 mmol/kg/h. It was somewhat lower in adult SHR, while renal clearance of nitrate was decreased significantly in this group. Lowering of blood pressure in SHR decreased the formation of NO. Treatment with NE did not evoke any difference in NO formation. The synthesis rate of NO in healthy men was estimated to 0.38±0.06 mmol/kg/h. It decreased to 0.17±0.03 mmol/kg/h after the same subjects were treated with L-NMMA. Conclusions. 15NO gas administered s.c. follows the same metabolic pathway as inhaled NO. Nitrate appears to be the main metabolite of endogenously formed NO. Nitrate excretion via faeces is not a significant route of elimination in healthy rats. Estimation of the formation of NO, both in laboratory animals and humans, was possible utilizing the 18-oxygen inhalation technique. This method may be useful in the assessment of various physiological and pathophysiological conditions affecting NO formatio

Unilateral adrenal hyperplasia is a usual cause of primary hyperaldosteronism. Results from a Swedish screening study

Abstract Background The existence of unilateral adrenal hyperplasia (AH) has been considered a rare cause of primary hyperaldosteronism (PA). Methods In a prospective study we screened for PA in a non-selected (NSP) and selected hypertensive population (SP), to define the cause of PA. We included 353 consecutive patients with hypertension; age 20 to 88 years, 165 women and 188 men, from a university-based Hypertension and Nephrology Outpatient clinics (123 SP) and two primary care centres, (230 NSP) from the same catch-up area. Serum aldosterone and plasma renin activity (PRA) were measured and the ARR calculated. Verifying diagnostic procedure was performed in patients with both elevated aldosterone and ARR. Patients diagnosed with PA were invited for adrenal venous sampling (AVS) and offered laparoscopic adrenalectomy when AVS found the disease to be unilateral. Results After screening, 46 patients, 13% of the whole population (22.8% SP and 7.8% NSP) had aldosterone and ARR above the locally defined cut-off limits (0.43 nmol/l and 1.28 respectively). After diagnostic verification, 20 patients (6%) had PA, (14.5% SP and 1.4% NSP). Imaging diagnostic procedures with CT-scans and scintigraphy were inconclusive. AVS, performed in 15 patients verified bilateral disease in 4 and unilateral in 10 patients. One AVS failed. After laparoscopic adrenalectomy, 4 patients were found to have adenoma and 5 unilateral AH. One patient denied operation. Conclusion The prevalence of PA was in agreement with previous studies. The study finds unilateral PA common and unilateral AH as half of those cases. As may be suspected PA is found in much higher frequency in specialised hypertensive units compared to primary care centers. AVS was mandatory in diagnosis of unilateral PA.</p

Unilateral adrenal hyperplasia is a usual cause of primary hyperaldosteronism. Results from a Swedish screening study.

To access publisher's full text version of this article. Please click on the hyperlink in Additional Links field.The existence of unilateral adrenal hyperplasia (AH) has been considered a rare cause of primary hyperaldosteronism (PA). In a prospective study we screened for PA in a non-selected (NSP) and selected hypertensive population (SP), to define the cause of PA. We included 353 consecutive patients with hypertension; age 20 to 88 years, 165 women and 188 men, from a university-based Hypertension and Nephrology Outpatient clinics (123 SP) and two primary care centres, (230 NSP) from the same catch-up area. Serum aldosterone and plasma renin activity (PRA) were measured and the ARR calculated. Verifying diagnostic procedure was performed in patients with both elevated aldosterone and ARR. Patients diagnosed with PA were invited for adrenal venous sampling (AVS) and offered laparoscopic adrenalectomy when AVS found the disease to be unilateral. After screening, 46 patients, 13% of the whole population (22.8% SP and 7.8% NSP) had aldosterone and ARR above the locally defined cut-off limits (0.43 nmol/l and 1.28 respectively). After diagnostic verification, 20 patients (6%) had PA, (14.5% SP and 1.4% NSP). Imaging diagnostic procedures with CT-scans and scintigraphy were inconclusive. AVS, performed in 15 patients verified bilateral disease in 4 and unilateral in 10 patients. One AVS failed. After laparoscopic adrenalectomy, 4 patients were found to have adenoma and 5 unilateral AH. One patient denied operation. The prevalence of PA was in agreement with previous studies. The study finds unilateral PA common and unilateral AH as half of those cases. As may be suspected PA is found in much higher frequency in specialised hypertensive units compared to primary care centers. AVS was mandatory in diagnosis of unilateral PA.Health & Medical Care Committee of the Regional Executive Board, Region Vastra Gotaland, Swede