###### Initial Clinic Meeting Drugs that interfere with the renin-angiotensin-aldosterone system should be discontinued: - Angiotensin converting enzyme inhibitors (lisinopril, enalapril, captopril) - Angiotensin receptor blockers (losartan, valsartan) - Mineralocorticoid receptor antagonists (spironolactone, eplerenone) - As these drugs increase renin levels, bilateral adrenal cortex stimulation would occur, falsely decreasing the rate of lateralization. Literature is variable about the length of time these medications should be discontinued. Some suspend them for 2 weeks (Deipolyi et al. 2015), others discontinue these for 8weeks (Lee et al. 2020) and still others also assess for suppressed plasma renin activity (< 0.6 ng/ml/hr) prior to proceeding with AVS (Kocjan et al. 2020). - Amlodipine, aoxazosin, hydralazine, diltiazem and nifedipine can be used as substitute antihypertensive agents. - Patients should be told to institute an unrestricted sodium diet as low sodium diets lead to bilateral aldosterone secretion. - Because discontinuing mineralocorticoid receptor blockers may lead to hypokalemic recidivism, serum potassium should be measured and, if < 3.5 mmol/L it should be corrected; low potassium inhibits aldosterone production and increases the proclivity of arrhythmias. ###### ACTH Stimulation - 0.25 mg Cortrosyn in 500 mL NS at 100 mL/hr - Start 1 hr before procedure (As soon as IV access is obtained) and continue throughout procedure ###### Labs: - Aldosterone, potassium, renin - Ask lab to titrate to max cortisol level Sample a minimum of 8 mL (4 mL for each tube) from each side. ###### Right side: - 5F renal double curve (RDC) - Vingan: USL, cobra1, MiKaelson, Sim1, Sim2 - Side hole 1 mm from tip on the superior surface - Place catheter up into IVC past adrenal vein - Turn posteriorly 1/8 turn (7 to 8 o'clock) - Look for deflection while pulling down - Look for inferior accessory hepatic vein, adrenal vein will be within 1 cm ###### Left side: - Simmons 3 or 2 - Use suture to form - Small hole on undersurface of the catheter - Phrenic-adrenal trunk - Always look for phrenic Selectivity index=Adrenal cortisol/IVC cortisol Needs to be >= 3 (or 5) Lateralization index = A/C (high)/A/C (low) Needs to be >= 4 for surgery ###### Example | | A | C | A/C | |-----|------|-----|-----| | R | 5000 | 500 | 10 | | L | 500 | 500 | 1 | | IVC | 100 | 50 | 2 | SI>3 (or 5) LI>4 ![[Adrenal Vein Sampling Trerotola.mp4]] Adrenal Vein Sampling Video - `URL:` https://www.youtube.com/watch?v=te5pvrOQWXs - `Description:` JVIR Adrenal Vein Sampling Final Cut - `Publish Date:` 05 October 2014 - `Duration`: 10:08 To follow up on your additional questions for AVS sampling at Quest: - The required specimen for this test is either a **red top** (serum without a separator gel), or **lavender top** (EDTA tube).  - I would recommend the red top, since that is more resistant to hemolysis. - The optimum volume is **2 mL serum/plasma** (~4 mL whole blood).  - The absolute minimum would be **0.5 mL serum/plasma** (1 mL whole blood). However, I would recommend collecting more than that, since it would be impossible to retest.  - Here is the link to the test available at quest: [Aldosterone/Cortisol Ratio, Adrenal Vein Sampling, 1 Site | Test Detail | Quest Diagnostics](https://testdirectory.questdiagnostics.com/test/test-detail/19573/aldosteronecortisol-ratio-adrenal-vein-sampling-1-site?p=r&q=adrenal%20venous%20sampling&cc=MASTER) For ordering, I believe you should be able to order these the same way as before. However, you could put the comment: "**Send to Quest. Test 19573**" just in case. Make sure to write diagnosis code **E26.09 Primary Hyperaldosteronism** on the lab order sheet.