ADRENAL VEIN SAMPLING: AN INTEGRAL PART OF MANAGING COMPLICATED ADRENAL HYPERTENSION- SAFE? WORTH IT?

Transcription

1 ADRENAL VEIN SAMPLING: AN INTEGRAL PART OF MANAGING COMPLICATED ADRENAL HYPERTENSION- SAFE? WORTH IT? Chaitanya Ahuja, M.D. Assistant Professor, Vascular and Interventional Radiology Director of Interventional Oncology LSU Health Science Center, Shreveport, LA

2 DISCLOSURES No conflict of interest relevant to this presentation

3 OUTLINE Indications and purpose Adrenal vein anatomy Procedure Technique of sampling Interpretation of results Complications

4 However, even though AVS may appear as a straightforward diagnostic test, it is used only in few centers worldwide. Even some major referral centers do not use AVS routinely as shown by a recent large survey, the Adrenal Vein Sampling International Study (AVIS). This underutilization is likely to be attributable to the misconception, largely based on anecdotal experiences and retrospective observational studies, that AVS is technically challenging, invasive, risky, and not always necessary, despite abundant evidence to the contrary. Hypertension.2014;63:

5 PRIMARY HYPERALDOSTERONISM High prevalence among drug resistant hypertension(> 11% of patients). May be due to bilateral idiopathic hyperplasia or unilateral adrenal adenoma. Surgery for unilateral adenoma; medical rx for bilateral hyperplasia. Cure of hypertension in unilateral adenoma up to 80%. Hypertension.2014;63:

6 ADRENAL VEIN SAMPLING : PURPOSE The purpose of Adrenal vein sampling is to establish if the autonomous hormone production is unilateral or bilateral irrespective of pathology. Sampling for lateralization AVS influences management in as many as 35.7% of patients who would have been treated incorrectly based on results of CT or other modalities White ML, et al Surgery

7 WHY CONVENTIONAL IMAGING IS NOT HELPFUL CT is unreliable as a screening test CT results inaccurate or noncontributory in 68% Adenomas less than 1 cm account for over 50% CT useful to rule out other diseases CT useful to demonstrate position of adrenal veins functioning rt adrenal adenoma indicates rt adrenal vein non functioning left adrenal adenoma

8 PATIENT SELECTION Laboratory analysis Plasma Aldosterone Concentration to Plasma Renin ratio (PAC/PRA) Normal PAC/PRA is 4-10 In primary aldosteronism PAC/PRA is ~30-50 PAC/PRA >32 (sensitivity 100%, specificity 61% for APA) APAs associated with more severe hypokalemia ( 3.0 meq/l) and higher plasma levels of aldosterone ( 25 ng/dl) compared to IHA Hirohara D, et al. J Clin Endocrinol Metab2001;86:

9 PATIENT PREPARATION Optimally performed in the morning Supine position for 1 hour prior to AVS Correct hypokalemia, if present Careful adjustment of antihypertensive agents before and during AVS MR antagonists or amiloride stopped for at least 4 weeks before AVS

10 ADRENAL VENOUS ANATOMY Drainage by a central vein bilaterally. Right side drains directly into the IVC. Left central vein drains into left renal vein.

11 ANATOMY VARIATIONS Duplication or triplication of vein. Right adrenal vein draining into phrenic vein. Right adrenal vein communicating with the hepatic vein. Retroaortic renal vein. Circumaortic venous ring.

12 ADRENAL VENOGRAPHY: TECHNIQUE Adrenal stimulation with IV ACTH (Cortrosyn 0.25mg). Differing protocols (Continuous cosyntropin infusion at 50 µg/h started at least 30 minutes before sampling or Single 250µg bolus during AVS). Heparin bolus prior to vein selection ( U/kg). Either simultaneous or sequential sampling. Catheterization and venography of each adrenal vein. Collection of samples. Assays for aldosterone and cortisol.

13 ADRENAL VENOGRAPHY: TECHNIQUE Venous access: Right common femoral puncture Peripheral line: Either any peripheral line or vascular sheath for peripheral blood samples Catheters: Cobra2 catheter with a side hole 3mm from tip. Other catheters used are Simmons1, Simmons 2, RDC

14

15 BILATERALLY SIMULTANEOUS OR SEQUENTIAL CATHETERIZATION Pulsatile secretion of aldosterone can generate timerelated variability in hormone concentrations. Consensus guidelines: If cosyntropin stimulation is used, sequential technique is acceptable but higher SI and LI thresholds are indicated. If no cosyntropin stimulation is used, bilateral simultaneous technique should be performed.

16 RIGHT ADRENAL VENOGRAPHY

17 RIGHT ADRENAL VENOGRAPHY

18 LEFT ADRENAL VENOGRAPHY

19

20 LEFT ADRENAL VEIN ORIGINATES FROM RETROAORTIC LEFT RENAL VEIN

21 RETROAORTIC LEFT RENAL VEIN - ADRENAL VEIN IN USUAL LOCATION Retroaortic left renal vein - adrenal vein in usual location

22 SIMULTANEOUS RIGHT AND LEFT VENOGRAPHY

23 ADRENAL VENOGRAPHY AND SAMPLING Injection should be gentle with only a small volume of contrast. Once a glandular pattern is recognized further injection is avoided. Cone beam CT. Adenomas can be outlined occasionally. Aspirate 8 ml using 10 ml syringe. Gentle suction. Allow it to drip freely from the catheter. Rapid assay for cortisol. Cortisol results: adrenal vein cortisol should be at least 3 x greater than peripheral vein cortisol.

24 CONE BEAM CT

25 RIGHT ADRENAL ADENOMAS

26 LEFT ADRENAL ADENOMAS

27 RIGHT ADRENAL ADENOMAS

28 AVS: RESULT INTERPRETATIONS

29 AVS: RESULT INTERPRETATIONS Selectivity Index (SI) = Adrenal vein:peripheral vein cortisol ratio. Successful catheterization of the adrenal vein is reflected in a selectivity index 3* Lateralization Index (LI) = Ipsilateral A/C: Contralateral A/C ratio. LI 4.0 denotes unilateral APA LI 2.0 denotes IHA LI borderline *When cosyntropin is used; SI 2 reflects consensus thresholdwhen cosyntropin is not used

30 AVS: RESULT INTERPRETATIONS Site Time Aldosterone Cortisol A/C Ratio Right Left Peripheral

31 PITFALLS Difficulty in catheterizing the right adrenal vein. Difficulty in aspirating blood False negative result if the catheter is deep seated.

32 AVS: RESULT INTERPRETATIONS June 24th Site Time Cortisol Right Left Peripheral July 1st Site Time Cortisol Right Left Peripheral

33 PITFALL RIGHT ADRENAL VEIN

34 SAFETY AND MANAGEMENT OF COMPLICATIONS In experienced hands, AVS is safe with very low complication rateadrenal vein rupture rate 0.61% in AVIS Dissection Infarction Intraglandular/periadrenal hematoma Vessel thrombosis Rossi GP, et al. J Clin Endocrinol Metab (5):

35 The high diagnostic accuracy and the very low rate of complications support the suggestion that AVS should serve as the gold standard diagnostic test for the subtyping of PA. Hypertension.2014;63:

36 CONCLUSIONS Adrenal vein sampling is rapid and safe Reliable and accurate Very tolerable with complication rate <1% With CT planning catheterization can be achieved in 90% cases Very important tool in evaluation of hyper-aldosteronism