Adrenal vein sampling with gadolinium contrast medium in a patient with florid primary aldosteronism and iodine allergy

Selective venous sampling for secondary hypertension

Selective venous sampling (SVS), an invasive radiographic procedure that depends on contrast media, holds a unique role in diagnosing and guiding the treatment of certain types of secondary hypertension, particularly in patients who may be candidates for curative surgery. The adrenal venous sampling (AVS), in particular, is established as the gold standard for localizing and subtyping primary aldosteronism (PA). Throughout decades of clinical practice, AVS could be applied not only to PA but also to other endocrine diseases, such as adrenal Cushing syndrome (ACS) and Pheochromocytomas (PCCs). Notably, the application of AVS in ACS and PCCs remains less recognized compared to PA, with the low success rate of catheterization, the controversy of results interpretation, and the absence of a standardized protocol. Additionally, the AVS procedure necessitates enhancements to boost its success rate, with several helpful but imperfect methods emerging, yet continued exploration remains essential. We also observed renal venous sampling (RVS), an operation akin to AVS in principle, serves as an effective means of diagnosing renin-dependent hypertension, aiding in the identification of precise sources of renin excess and helping the selection of surgical candidates with renin angiotensin aldosterone system (RAAS) abnormal activation. Nonetheless, further basic and clinical research is needed. Selective venous sampling (SVS) can be used in identifying cases of secondary hypertension that are curable by surgical intervention. Adrenal venous sampling (AVS) and aldosterone measurement for classificatory diagnosis of primary aldosteronism (PA) are established worldwide. While its primary application is for PA, AVS also holds the potential for diagnosing other endocrine disorders, including adrenal Cushing's syndrome (ACS) and pheochromocytomas (PCCs) through the measurements of cortisol and catecholamine respectively. In addition, renal venous sampling and renin measurement can help to diagnose renovascular hypertension and reninoma.

Contrast medium free selective adrenal vein sampling in the management of primary aldosteronism

BACKGROUND

To analyze contrast free adrenal vein sampling (AVS) for differentiating unilateral from bilateral disease in patients diagnosed with hypertension due to primary aldosteronism (PA).

METHODS

Consecutive patients with PA and subsequent contrast medium free AVS between April 2015 and March 2020 were retrospectively included. Cross-sectional imaging (CSI), AVS and clinical data were analyzed regarding diagnostic performance. In addition, patients with lateralisation receiving adrenalectomy were compared to a control group treated with mineralocorticoid antagonists.

RESULTS

In total 186 patients with AVS were included. The success rate for bilateral catheterization was 88% (median effective dose 2.8 mSv). CSI had an accuracy of 60% (CI: 0.52-0.67) in the detection of lateralization compared to AVS. Patients with bilateral adrenal hyperplasia and those with aldosterone-producing adenoma did not differ in systolic blood pressure (sBP) (p = 0.63) or number of antihypertensive drugs (NAD) (p = 0.11). After adrenalectomy, 28 patients were cured (51%; sBP ≤130 mmHg, NAD = 0), 18 were improved (33%; decrease of sBP ≥20 mmHg and NAD), and 8 were unchanged (15%). Serum renin increased significantly after treatment (p < 0.01).

CONCLUSION

Contrast medium free AVS is a reliable procedure in the diagnostic management of patients with PA with high technical success rate. The accordance between CSI and results from AVS was only moderate indicating the central role of AVS in the diagnostic work-up of patients with PA. Patients with predominant disease diagnosed with AVS had a high cure rate and/or significant improvement after adrenalectomy.

Successful Adrenal Vein Sampling Using Dexamethasone Premedication in Patients With Iodine Contrast Media Allergy

Context

Preparation of patients with iodine contrast media (ICM) allergy who require adrenal vein sampling (AVS) to establish source of aldosterone excess of their confirmed primary aldosteronism (PA) is controversial. Usual premedication with high-dose prednisone can interfere with cortisol determinations, possibly altering the aldosterone to cortisol ratios for the identification of lateralized aldosterone excess.

Objective

We aimed to evaluate the efficacy and safety of premedication with high-dose dexamethasone to perform AVS in patients with ICM.

Methods

One hundred and seventy-seven consecutive patients with confirmed PA who underwent bilateral simultaneous basal and post-ACTH bolus AVS at our center between January 2010 and December 2020 were retrospectively analyzed for history of ICM allergy. A total of 7 patients (4%) with previous allergic reactions to ICM were prepared with 3 doses of 7.5 mg dexamethasone premedication rather than the usual 50 mg of prednisone.

Results

No breakthrough allergic reactions were reported in the 7 patients. Despite adequate serum cortisol suppression following dexamethasone, the basal and post-ACTH selectivity index were respectively &gt; 2 and &gt; 5 bilaterally in all patients, confirming adequate cannulation of both adrenal veins. Four patients had lateralized ratios (A/C ratio &gt; 2 basally and &gt; 4 post-ACTH), while 3 had bilateral source during AVS study. In the 3 patients undergoing unilateral adrenalectomy for lateralized source and contralateral suppression and adequate follow-up data, cure of PA was achieved at mean 58 months postoperatively.

Conclusion

AVS using dexamethasone premedication is safe and accurate for diagnosing the source of aldosterone excess in patients with PA and ICM allergy.