The Occurrence of Apparent Bilateral Aldosterone Suppression in Adrenal Vein Sampling for Primary Aldosteronism

Adrenal Vein Sampling for Primary Aldosteronism: Recommendations From the Australian and New Zealand Working Group

Adrenal vein sampling (AVS) is the current recommended procedure for identifying unilateral subtypes of primary aldosteronism (PA), which are amenable to surgery with the potential for cure. AVS is a technically challenging procedure usually undertaken by interventional radiologists at tertiary centres. However, there are numerous variations in AVS protocols relating to patient preparation, sampling techniques and interpretation which may impact the success of AVS and patient care. To reduce practice variations, improve the success rates of AVS and optimise patient outcomes, we established an Australian and New Zealand AVS Working Group and developed evidence-based expert consensus recommendations for the preparation, performance and interpretation of AVS. These recommendations can be used by all healthcare professionals in a multidisciplinary team who look after the diagnosis and management of PA.

Segmental Adrenal Venous Sampling in Unilateral Primary Aldosteronism With Apparent Bilateral Aldosterone Suppression

Apparent bilateral adrenal suppression (ABAS), where aldosterone/cortisol ratios in both adrenal veins are lower than in the inferior vena cava, yields uninterpretable adrenal venous sampling (AVS) results and is poorly understood. A 57-year-old male with hypertension and spontaneous hypokalemia was admitted to our hospital. Confirmatory tests established a diagnosis of primary aldosteronism (PA). Initial AVS indicated ABAS, but unilateral PA remained possible due to elevated aldosterone, low renin, hypokalemia, and a right adrenal nodule (8 × 7 mm) on computed tomography. Subsequently, a second, super-selective AVS identified tributaries from areas of aldosterone hypersecretion, enabling accurate localization of unilateral PA. ABAS may occur due to anatomical factors such as dilution by tributaries from nonaldosterone-producing adenoma (APA) areas with suppressed aldosterone production. Super-selective AVS proves beneficial in diagnosing unilateral PA concealed within ABAS by pinpointing tributaries from APA regions.

Adrenal Vein Sampling: Tips and Tricks

Adrenal vein sampling (AVS) is the standard method for distinguishing unilateral from bilateral sources of autonomous aldosterone production in patients with primary aldosteronism. This procedure has been performed at limited specialized centers due to its technical complexity. With recent advances in imaging technology and knowledge of adrenal vein anatomy in parallel with the development of adjunctive techniques, AVS has become easier to perform, even at nonspecialized centers. Although rare, anatomic variants of the adrenal veins can cause sampling failure or misinterpretation of the sampling results. The inferior accessory hepatic vein and the inferior emissary vein are useful anatomic landmarks for right adrenal vein cannulation, which is the most difficult and crucial step in AVS. Meticulous assessment of adrenal vein anatomy on multidetector CT images and the use of a catheter suitable for the anatomy are crucial for adrenal vein cannulation. Adjunctive techniques such as intraprocedural cortisol assay, cone-beam CT, and coaxial guidewire-catheter techniques are useful tools to confirm right adrenal vein cannulation or to troubleshoot difficult blood sampling. Interventional radiologists should be involved in interpreting the sampling results because technical factors may affect the results. In rare instances, bilateral adrenal suppression, in which aldosterone-to-cortisol ratios of both adrenal glands are lower than that of the inferior vena cava, can be encountered. Repeat sampling may be necessary in this situation. Collaboration with endocrinology and laboratory medicine services is of great importance to optimize the quality of the samples and for smooth and successful operation. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Utility of Repeat Sampling in Bilateral Aldosterone Suppression During Adrenal Vein Sampling for Primary Aldosteronism

Primary aldosteronism (PA) is the most common form of secondary hypertension. Accurate subtyping of PA is essential to identify unilateral disease, as adrenalectomy improves outcomes. Subtyping PA requires adrenal vein sampling (AVS), which is technically challenging and results from AVS may not always be conclusive. We present a case of a 37-year-old man with PA whose AVS studies were inconclusive due to apparent bilateral aldosterone suppression (ABAS). As a result, our patient was misdiagnosed as having bilateral PA and medically managed until a repeat AVS showed lateralization to the right adrenal gland. ABAS is an underrecognized phenomenon that may confound the subtyping of PA. We recommend repeating AVS in such cases and discuss strategies to minimize ABAS.

Role of Adrenal Vein Sampling in Guiding Surgical Decision in Primary Aldosteronism

Adrenal vein sampling (AVS) is recommended for subtyping primary aldosteronism (PA) to identify lateralized or bilateral sources of aldosterone excess, allowing for better decision-making in regard to medical or surgical management on a case-by-case basis. To date, no consensus exists on protocols to be used during AVS, especially concerning sampling techniques, the timing of sampling, and whether or not to use adrenocorticotropic hormone (ACTH) stimulation. Interpretation criteria for selectivity, lateralization, and contralateral suppression vary from one expert center to another, with some favoring strict cut-offs to others being more permissive. Clinical and biochemical post-operative outcomes can also be influenced by AVS criteria utilized to indicate surgical therapy.In this review, we reanalyze studies on AVS highlighting the recent pathological findings of frequent micronodular hyperplasia adjacent to a dominant aldosteronoma (APA) overlapping with bilateral idiopathic hyperaldosteronism (IHA) etiologies, as opposed to the less frequent unilateral single aldosteronoma. The variable expression of melanocortin type 2 receptors in the nodules and hyperplasia may explain the frequent discordance in lateralization ratios between unstimulated and ACTH- stimulated samples. We conclude that aldosterone values collected during simultaneous bilateral sampling, both at baseline and post-ACTH stimulation, are required to adequately evaluate selectivity, lateralization, and contralateral suppression during AVS, to better identify all patients with PA that can benefit from a surgical indication. Recommended cut-offs for each ratio are also presented.

Validation of three novel clinical prediction tools for primary aldosteronism subtyping

The 20-point clinical prediction SPACE score, the aldosterone-to-lowest potassium ratio (APR), aldosterone concentration (AC) and the AC relative reduction rate after saline infusion test (SIT) have recently been proposed for primary aldosteronism (PA) subtyping prior to adrenal vein sampling (AVS). To validate those claims, we performed a retrospective cross-sectional study that included all patients at our center who had positive SIT to confirm PA and were diagnosed with either bilateral disease (BPA) according to AVS or with lateralized disease (LPA) if biochemically cured after adrenalectomy from November 2004 to the end of 2019. Final diagnoses were used to evaluate the diagnostic performance of proposed clinical prediction tools. Our cohort included 144 patients (40 females), aged 32-72 years (mean 54 years); 59 with LPA and 85 with BPA. The originally suggested SPACE score ≤8 and SPACE score >16 rules yielded about 80% positive predictive value (PPV) for BPA and LPA, respectively. Multivariate analyses with the predictors constituting the SPACE score highlighted post-SIT AC as the most important predictor of PA subtype for our cohort. APR-based tool of <5 for BPA and >15 for LPA yielded about 75% PPV for LPA and BPA. The proposed post-SIT AC <8.79 ng/dL criterion yielded 41% sensitivity and 90% specificity, while the relative post-SIT AC reduction rate of >33.8% criterion yielded 80% sensitivity and 51% specificity for BPA prediction. The application of any of the validated clinical prediction tools to our cohort did not predict the PA subtype with the high diagnostic performance originally reported.

Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021

Primary aldosteronism (PA) is associated with higher cardiovascular morbidity and mortality rates than essential hypertension. The Japan Endocrine Society (JES) has developed an updated guideline for PA, based on the evidence, especially from Japan. We should preferentially screen hypertensive patients with a high prevalence of PA with aldosterone to renin ratio ≥200 and plasma aldosterone concentrations (PAC) ≥60 pg/mL as a cut-off of positive results. While we should confirm excess aldosterone secretion by one positive confirmatory test, we could bypass patients with typical PA findings. Since PAC became lower due to a change in assay methods from radioimmunoassay to chemiluminescent enzyme immunoassay, borderline ranges were set for screening and confirmatory tests and provisionally designated as positive. We recommend individualized medicine for those in the borderline range for the next step. We recommend evaluating cortisol co-secretion in patients with adrenal macroadenomas. Although we recommend adrenal venous sampling for lateralization before adrenalectomy, we should carefully select patients rather than all patients, and we suggest bypassing in young patients with typical PA findings. A selectivity index ≥5 and a lateralization index >4 after adrenocorticotropic hormone stimulation defines successful catheterization and unilateral subtype diagnosis. We recommend adrenalectomy for unilateral PA and mineralocorticoid receptor antagonists for bilateral PA. Systematic as well as individualized clinical practice is always warranted. This JES guideline 2021 provides updated rational evidence and recommendations for the clinical practice of PA, leading to improved quality of the clinical practice of hypertension.

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

We describe a 35-year-old woman who was allergic to iodine contrast medium and was diagnosed with primary aldosteronism (PA) based on functional confirmatory tests. She was suspected to have unilateral PA because of marked hypertension, spontaneous hypokalemia, high plasma aldosterone, reduced plasma renin activity, and a right hypodense adrenal tumor. She wanted to become pregnant and requested adrenalectomy instead of medical treatment with mineralocorticoid receptor antagonists. Localization of PA by adrenal vein sampling (AVS) was necessary, but angiography with iodine contrast medium was not possible because of her allergy. AVS was performed using gadolinium contrast agent (gadoterate meglumine) instead of iodine, in combination with computed tomography angiography (CTA). In AVS, before and after adrenocorticotropin (ACTH) loading, 12 blood samples were drawn from the right adrenal vein, left adrenal central vein, left adrenal common duct, left and right renal veins, and the lower inferior vena cava with only 5 mL of gadolinium medium. There were no complications during AVS. Examination revealed an elevated aldosterone/cortisol ratio on the right side, lateralized ratio of 7.4, and contralateral ratio of 0.76; the patient was diagnosed with right unilateral PA. She underwent right adrenalectomy and showed improvements in aldosterone level from 312.4 pg/mL to 83.0 pg/mL, potassium from 3.0 mEq/L to 3.9 mEq/L, and systolic blood pressure from 138 mm Hg to 117 mm Hg. In PA patients with iodine allergy, AVS can be performed safely and precisely using gadolinium contrast combined with CTA.

Adrenal venous sampling with adrenocorticotropic hormone stimulation: A meta-analysis

BACKGROUND

This meta-analysis was performed to compare the effect of adrenal venous sampling with adrenocorticotropic hormone with that without adrenocorticotropic hormone in subjects with primary aldosteronism.

METHODS

A systematic literature search up to May 2020 was performed and 17 studies were detected with 1878 subjects who had adrenal venous sampling operations. They reported relationships between with and without adrenocorticotropic hormone stimulation during adrenal venous sampling in subjects with primary aldosteronism. We calculated the odds ratio (OR) with 95% confidence intervals (CIs), using the dichotomous method with a random- or fixed-effect model.

RESULTS

Adrenal venous sampling operations with adrenocorticotropic hormone stimulation had statistically significant lower incorrect lateralisation (OR, 0.57; 95% CI, 0.43-0.75, P < .001); lower unsuccessful cannulations in both adrenal veins (OR, 0.35; 95% CI, 0.21-0.58, P < .001); lower unsuccessful cannulations of left adrenal vein (OR, 0.10; 95% CI, 0.06-0.17, P < .001) and lower unsuccessful cannulations of right adrenal vein (OR, 0.25; 95% CI, 0.11-0.54, P < .001) compared with without adrenocorticotropic hormone stimulation in subjects with primary aldosteronism.

CONCLUSIONS

Adrenal venous sampling operations with adrenocorticotropic hormone stimulation had significantly lower incorrect lateralisation, unsuccessful cannulations in both adrenal veins, unsuccessful cannulations of the left adrenal vein and unsuccessful cannulations of the right adrenal vein compared with adrenal venous sampling operations without adrenocorticotropic hormone stimulation in subjects with primary aldosteronism. Larger prospective studies are recommended to confirm these findings.

Machine learning based models for prediction of subtype diagnosis of primary aldosteronism using blood test

Primary aldosteronism (PA) is associated with an increased risk of cardiometabolic diseases, especially in unilateral subtype. Despite its high prevalence, the case detection rate of PA is limited, partly because of no clinical models available in general practice to identify patients highly suspicious of unilateral subtype of PA, who should be referred to specialized centers. The aim of this retrospective cross-sectional study was to develop a predictive model for subtype diagnosis of PA based on machine learning methods using clinical data available in general practice. Overall, 91 patients with unilateral and 138 patients with bilateral PA were randomly assigned to the training and test cohorts. Four supervised machine learning classifiers; logistic regression, support vector machines, random forests (RF), and gradient boosting decision trees, were used to develop predictive models from 21 clinical variables. The accuracy and the area under the receiver operating characteristic curve (AUC) for predicting of subtype diagnosis of PA in the test cohort were compared among the optimized classifiers. Of the four classifiers, the accuracy and AUC were highest in RF, with 95.7% and 0.990, respectively. Serum potassium, plasma aldosterone, and serum sodium levels were highlighted as important variables in this model. For feature-selected RF with the three variables, the accuracy and AUC were 89.1% and 0.950, respectively. With an independent external PA cohort, we confirmed a similar accuracy for feature-selected RF (accuracy: 85.1%). Machine learning models developed using blood test can help predict subtype diagnosis of PA in general practice.

"Double-Down" Adrenal Vein Sampling Results in Patients with Apparent Bilateral Aldosterone Suppression: Utility of Repeat Sampling including Super-Selective Sampling

PURPOSE

To report outcomes of patients undergoing adrenal vein sampling (AVS) for primary aldosteronism with results indicating apparent bilateral adrenal suppression (ABAS), in which the adrenal aldosterone-to-cortisol ratios are decreased bilaterally ("double-down") compared to the non-adrenal sample, and evaluate repeat AVS results.

MATERIALS AND METHODS

Between 2003 and 2020, 762 patients underwent AVS. Twenty patients (2.6%; male, 12; female, 8; age 50.3 ± 9.7 years) with ABAS on initial AVS were identified. Ten underwent repeat AVS. Super-selective AVS (SS-AVS) was employed in 6 of 10 repeat AVS (60%). Outcomes after AVS were analyzed. A lateralization index (LI) >4 was considered an indication for adrenalectomy.

RESULTS

Repeat AVS was diagnostic in 70% of patients (n = 7), with 6 of 7 lateralizing with LI >4 (median LI = 32.3; range 4.6-54.8) and 1 of 7 nearly lateralizing (LI = 3.5). All 7 patients underwent adrenalectomy. ABAS was redemonstrated in 3 patients (30%): 2 with unilateral adenomas on cross-sectional imaging underwent adrenalectomy despite ABAS results and 1 was lost to follow-up. Four of 6 patients (66%) who underwent SS-AVS were diagnosed with unilateral disease (median LI = 43.3; range 23.9-54.8), with one patient's diagnosis reliant upon a single super-selective sample. In total, 9 patients underwent adrenalectomy after repeat AVS, all of whom had improved blood pressure control postoperatively. Ten patients did not undergo repeat AVS: 6 were lost to follow-up, 3 underwent medical management, and 1 underwent adrenalectomy.

CONCLUSIONS

AVS should be repeated when "double-down" ABAS results are encountered. Super-selective sampling may provide worthwhile diagnostic data when employed during repeat AVS.

Prediction of unilateral hyperaldosteronism on adrenal vein sampling using captopril challenge test in patients with primary aldosteronism

Captopril challenge test (CCT) is a simple and safe confirmatory test for primary aldosteronism (PA). We investigated the effectiveness of the indices after captopril administration for prediction of unilateral hyperaldosteronism (UHA) on adrenal vein sampling (AVS). We studied 238 patients with PA who had CCT and successful AVS between July 2007 and December 2019 in Sapporo City General Hospital. Receiver operating characteristic (ROC) curve analysis showed that the diagnostic performance for prediction of UHA on AVS in regard to the reduction rate of plasma aldosterone concentration (PAC) after captopril administration was inferior to aldosterone to renin ratio (ARR) and PAC (area under the ROC curve 0.72 vs. 0.84, 0.72 vs. 0.89, respectively, both p < 0.01). Based on the optimal cut-off values in ARR (897 pg/mL/ng/mL/h, sensitivity 64.6%, specificity 93.0%) and PAC (203 pg/mL, sensitivity 73.9%, specificity 93.0%) after captopril administration, the patients were divided into three groups: (1) both positive, (2) one positive, and (3) both negative. The prevalence of UHA on AVS in the three groups were 90.0%, 52.9%, and 7.3%, respectively. In the first group, 31 of 32 patients with unilateral nodular lesion on CT had an ipsilateral unilateral AVS. In conclusion, the combination of post-captopril ARR and PAC is useful for prediction of laterality diagnosis on AVS. AVS is strongly recommended in patients with both positive or one positive results for the optimal cut-off values of post-captopril ARR and PAC and is weakly recommended in patients with both negative results.

Influence of antihypertensive drugs in the subtype diagnosis of primary aldosteronism by adrenal venous sampling

OBJECTIVES

Because of the influence on the renin-angiotensin-aldosterone system, it is recommended to avoid, if possible, the use of angiotensin-converting-enzyme inhibitors, angiotensin II type 1 receptor blockers, diuretics, β-blockers, and mineralocorticoid receptor antagonists during the diagnostic period of primary aldosteronism. A laterality index more than 4 in adrenocorticotropic hormone (ACTH)-stimulated adrenal venous sampling (ACTH-AVS) is a widely used classification of the unilateral subtype that can benefit from adrenalectomy. Here, we revealed clinical features of patients taking drugs that could affect the primary aldosteronism diagnosis (DAPD) and investigated whether the classification with laterality index more than 4 in ACTH-AVS is applicable to these patients.

PATIENTS AND METHODS

Using a large database of primary aldosteronism patients in Japan, we analyzed 2122 patients with successful ACTH-AVS.

RESULTS

Patients who received any DAPD (n = 209) showed higher prevalence of comorbidity burdens and took more antihypertensive drugs compared with patients without DAPD. In patients taking DAPD, those with laterality index more than 4 had a higher prevalence of hypokalemia, a higher aldosterone-to-renin ratio and a higher prevalence of adrenal mass than those with laterality index of 4 or less. Adrenalectomy was performed in 76% patients with laterality index more than 4 and 20% with laterality index of 4 or less. Patients who underwent adrenalectomy showed biochemical cure in 89% with laterality index more than 4 and 50% with laterality index of 4 or less (P = 0.001). Multivariate regression analysis showed that laterality index more than 4 was an independent predictor of a biochemical cure. Biochemical cure rate in patients with laterality index more than 4 was consistently high, irrespective of the potential effect of individual DAPD on laterality index.

CONCLUSION

Our findings suggest that in primary aldosteronism patients to whom DAPD were administrated due to severe clinical features, laterality index more than 4 in ACTH-AVS could accurately predict a biochemical cure after adrenalectomy.

Controversies and advances in adrenal venous sampling in the diagnostic workup of primary aldosteronism

Adrenal venous sampling (AVS) is a key part of the diagnostic workup of primary aldosteronism, distinguishing unilateral from bilateral disease and determining treatment options. Although AVS is a well-established procedure, many aspects remain controversial, including optimal patient selection for the procedure and exactly how AVS is performed and interpreted. Despite the controversies, a growing body of evidence supports the use of AVS in most patients with primary aldosteronism, though some specific patient groups may be able to forego AVS and proceed directly to treatment. Although AVS remains a difficult procedure, success rates may be improved with the use of advanced CT imaging techniques and/or rapid cortisol assays. New advances in nuclear imaging and steroid profiling may also offer alternatives or adjuncts to AVS in the future.

Cosyntropin stimulation in adrenal vein sampling improves the judgment of successful adrenal vein catheterization and outcome prediction for primary aldosteronism

The importance of cosyntropin stimulation during adrenal vein sampling (AVS) is not fully established, partly due to insufficient AVS data relating the presence and absence of cosyntropin stimulation with postoperative outcome. Therefore, we investigated differences in AVS indices before and after cosyntropin stimulation, and determined whether unstimulated or stimulated AVS indices better correlated with treatment outcome. A retrospective study was conducted in two parts: one with 185 patients who underwent AVS and the other with 81 patients who underwent unilateral adrenalectomy for unilateral aldosterone oversecretion. The selectivity index (SI), lateralized ratio (LR), and contralateral ratio (CR) before and after cosyntropin stimulations were determined, along with blood pressure outcome 1 year after surgery. Primary aldosteronism was diagnosed according to the Japanese Endocrine Society 2009 guidelines. The percentage of AVS patients with successful catheterization, defined as unstimulated SI > 2 before and stimulated SI > 5, increased after cosyntropin stimulation from 52% to 93% and from 74% to 98% for the right and left adrenal veins, respectively. LR decreased after cosyntropin stimulation (P < 0.001). In the postoperative patients, complete and partial clinical success was achieved in 49 and 27%, respectively. Low CR (<1) and high LR (≥2.6) after cosyntropin stimulation better correlated with postoperative blood pressure outcome than those before stimulation (CR < 1 and LR ≥ 2). These data suggest that cosyntropin stimulation facilitated the judgment of catheter insertion and postcosyntropin AVS indices may be more useful for predicting treatment outcome after unilateral adrenalectomy. Further study should examine the usefulness of cosyntropin stimulation in AVS performed in other settings.

Role of Aldosterone and Potassium Levels in Sparing Confirmatory Tests in Primary Aldosteronism

CONTEXT

The current clinical guidelines suggest that confirmatory tests for primary aldosteronism (PA) may be excluded in some of patients who have elevated plasma aldosterone concentration (PAC) under plasma renin suppression. However, this has low-priority evidence and is under debate in use of serum potassium.

OBJECTIVE

This study aimed to investigate an appropriate setting for sparing confirmatory tests in PA.

DESIGN AND SETTING

A retrospective cross-sectional study in a single referral center.

PARTICIPANTS

This study included 327 patients who had hypertension under plasma renin suppression and underwent the captopril challenge test (CCT) between January 2007 and April 2019. CCT results were used to diagnose PA.

MAIN OUTCOME MEASURE

Diagnostic value of PAC and serum potassium in confirmation of PA.

RESULTS

Of the studied patients, 252 of 327 (77%) were diagnosed with PA. All 61 patients with PAC > 30 ng/dL were diagnosed with PA. In patients with PAC between 20 and 30 ng/dL, 44 of 55 (80%) were diagnosed with PA, while all 26 with PAC between 20 to 30 ng/dL who had spontaneous hypokalemia were diagnosed with PA. The proportion of unilateral PA determined by adrenal vein sampling (AVS) was higher in patients who had PAC > 30 ng/dL or those with spontaneous hypokalemia who had PAC between 20 and 30 ng/dL than those who did not meet the criteria (76% vs. 17%, P < .001).

CONCLUSION

Confirmatory tests in PA could be spared in patients who have typical features of PA and these patients had a high probability of unilateral PA on AVS.

Bilateral Aldosterone Suppression in Patients With Right Unilateral Primary Aldosteronism and Review of the Literature

Introduction

Adrenal vein sampling (AVS) identifies unilateral primary aldosteronism but may occasionally show paradoxically low aldosterone–cortisol ratios bilaterally. Postulated reasons include venous anomalies, fluctuating aldosterone secretion, or superselective cannulation. We report our findings in patients who underwent repeat AVS and reviewed the current literature.

Methods

We performed a retrospective observational study of patients undergoing AVS in an experienced high-volume tertiary center over a 5-year period.

Results

From 2015 to 2019, 61 patients underwent sequential cosyntropin-stimulated AVS and all had bilateral successful cannulation (100%). Four of 61 (6.6%) patients had bilaterally low aldosterone–cortisol ratios. Three patients underwent repeat AVS, with all 3 cases demonstrating right-sided lateralization and cure of disease postadrenalectomy. Right-sided disease was also more common in other reports. This may be due to inadvertent superselective cannulation of the short right adrenal vein, resulting in sampling of the adjacent normal gland. Cortisol results cannot detect this problem. In 1 patient, computed tomography venography excluded any accessory right adrenal veins. In another patient, repeat bilateral simultaneous unstimulated AVS was done, and measurements of metanephrines aided in accurately identifying right-sided lateralization.

Conclusion

In addition to technical difficulties in cannulating the right adrenal vein, we also have to avoid performing superselective cannulation inadvertently. In cases of inconclusive AVS, repeat sampling may identify patients with potentially curable unilateral primary aldosteronism. The role of corticotropin stimulation and metanephrines measurements during repeat AVS requires further study.

Can incomplete adrenal venous sampling data be used in predicting the subtype of primary aldosteronism?

BACKGROUND

Adrenal venous sampling (AVS) is the gold standard for preoperative differentiation between unilateral and bilateral primary aldosteronism (PA). However, results are sometimes vitiated by failing to access the right adrenal vein.

MATERIALS AND METHODS

The present study assumed that clinical decisions can be made with incomplete AVS data, by comparing aldosterone/cortisol (A/C) ratio in both left and right adrenal veins with that in the inferior vena cava (LAV/IVC and RAV/IVC). Receiver operation characteristic (ROC) curve and scatterplot were used to certify the upper and lower cutoffs and to analyze the significance of discrimination. One hundred and sixty patients diagnosed with PA from April 2017 to June 2018 underwent AVS in the Urology Department of West China Hospital, Chengdu, China. One hundred and eleven with complete AVS data were divided into 3 groups: left-sided (N=40), right-sided (N=29) and bilateral (N=42). We also collected patients from September 2018 to April 2019 in our department as validation cohort to test our hypothesis.

RESULTS

On the basis of LAV/IVC, RAV/IVC and diagnostic category, upper cutoff was 1.14 (50% sensitivity and 100% specificity) and lower cutoff 0.07 (27.5% sensitivity and 100% specificity) for LAV/IVC, and 1.04 (55% sensitivity and 100% specificity) and 0.08 (40% sensitivity and 100% specificity), respectively, for RAV/IVC.

CONCLUSION

The diagnostic model in this study contributes to clinical decision-making in patients with only partial PA with incomplete AVS data.

Predictors of Clinical Success After Surgery for Primary Aldosteronism in the Japanese Nationwide Cohort

Context

Aldosterone-producing adenomas are a curable subtype of primary aldosteronism (PA); however, hypertension persists in some patients after adrenalectomy.

Objective

To identify factors associated with, and develop prediction models for, blood pressure (BP) normalization or improvement after adrenalectomy.

Design

Retrospective analysis of patients treated between 2006 and 2018, with a 6-month follow-up.

Setting

A nationwide, 29-center Japanese registry encompassing 15 university hospitals and 14 city hospitals.

Patients

We categorized 574 participants in the Japan Primary Aldosteronism Study, who were diagnosed with PA and underwent adrenalectomy, as BP normalized or improved, on the basis of their presentations at 6 months postsurgery.

Main Outcome Measure

The rate of complete, partial, and absent clinical success. Predictive factors related to BP outcomes after PA surgery were also evaluated.

Results

Complete clinical success was achieved in 32.6% and partial clinical success was achieved in 53.0% of the patients at 6 months postsurgery. The following five variables were independent predictors for BP normalization: ≤7 years of hypertension, body mass index ≤25 kg/m², no more than one antihypertensive medication, absence of medical history of diabetes, and female sex. The area under the receiver operator characteristic curve was 0.797 in the BP normalization model.

Conclusion

We established models that predicted postoperative BP normalization in patients with PA. These should be useful for shared decision-making regarding adrenalectomy for PA.

Lateralizing Asymmetry of Adrenal Imaging and Adrenal Vein Sampling in Patients With Primary Aldosteronism

Context

In patients with primary aldosteronism (PA), it remains unclear whether aldosterone-producing adenomas are likely to develop in the left or right adrenal gland.

Objective

To investigate left-right differences of PA laterality diagnoses via CT imaging and adrenal vein sampling (AVS).

Design

Retrospective, observational study.

Patients

From the Japan Primary Aldosteronism Study, 1493 patients with PA were enrolled who underwent CT and ACTH-stimulated AVS.

Measurements

Left or right adrenal nodular lesion distribution and laterality observed on CT scans and from AVS were noted.

Results

Both on CT scans and AVS, unilateral results were observed more frequently on the left side than on the right side (25.1% vs 15.4% and 17.3% vs 13.5%, respectively; P < 0.01for both diagnostic techniques). There was no significant difference in the concordance rate for CT and AVS between patients with left and right unilateral nodular lesions observed on CT scans (44.1% and 50.9%, respectively; P = 0.15). In patients with nodules <20 mm, the concordance rate was significantly greater on the right side than the left side (45.8% vs 56.4%; P = 0.03). In patients with bilateral results of AVS, unilateral nodular lesions were detected more frequently on the left side than the right side (17.8% vs 9.4%; P < 0.01).

Conclusion

These results suggest aldosterone-producing adenomas and nonfunctioning tumors are more likely to develop on the left side in patients with PA and that misdiagnosis of CT-based lateralization may occur more frequently on the left side.

Adrenal venous sampling with or without adrenocorticotropic hormone stimulation: A meta-analysis

CONTEXT

Adrenal venous sampling (AVS) with or without adrenocorticotropic hormone (ACTH) stimulation is the test of choice to identify patients with a surgically curable subtype of primary aldosteronism (PA). Whether AVS with ACTH stimulation is more effective than AVS without ACTH stimulation remains controversial.

OBJECTIVE

To compare the effectiveness of AVS with ACTH stimulation and AVS without ACTH stimulation in patients with PA.

METHODS

The Cochrane Library, PubMed, Embase, and Web of Science databases were searched to identify relevant articles. All cohort studies comparing the 2 techniques (AVS with ACTH stimulation and AVS without ACTH stimulation in patient with PA) were included in the analysis.

RESULTS

A total of 14 studies met the inclusion criteria, and they were analyzed. AVS with ACTH stimulation did not significantly reduce the number of incorrect lateralization more than AVS without ACTH stimulation in patients with PA [OR: 0.76, 95% confidence interval (CI): 0.36, 1.59; P=0.47]. AVS with ACTH stimulation significantly reduced the number of unsuccessful cannulations of both adrenal veins more than AVS without ACTH stimulation in patients with PA (OR: 0.26, 95% CI: 0.17, 0.40; P<0.00001). For subgroup analyses, it also significantly reduced the number of unsuccessful cannulations of left adrenal vein and right adrenal vein (OR: 0.14, 95% CI: 0.06, 0.33; P<0.00001 and OR: 0.30, 95% CI: 0.12, 0.71; P=0.007, respectively).

CONCLUSION

AVS with ACTH stimulation can significantly reduce the number of unsuccessful cannulations, without significantly reducing the number of incorrect lateralization. Further studies are still needed to verify these findings.

Relationship Between Visceral Fat and Plasma Aldosterone Concentration in Patients With Primary Aldosteronism

Context

The involvement of visceral fat in aldosterone secretion has not been reported in patients with primary aldosteronism (PA). Patients with PA are complicated by metabolic syndrome more frequently than those without PA. An excess of visceral fat has been hypothesized to cause an elevation of aldosterone secretion in patients with PA.

Objectives

To clarify the role of visceral fat in the pathophysiology of PA, we investigated the correlation between plasma aldosterone concentration (PAC) and visceral fat parameters in patients with PA.

Design

This retrospective observational study comprised 131 patients diagnosed with PA between April 2007 and April 2017 at Sapporo City General Hospital. We divided participants into two PA subtypes, aldosterone-producing adenoma (APA; n = 47) and idiopathic hyperaldosteronism (IHA, n = 84), utilizing adrenal venous sampling. We analyzed the correlations of PAC with visceral fat percentage (VF%), visceral fat area (VFA), and subcutaneous fat area, by evaluating computed tomography studies in each subtype group.

Results

Patients with IHA showed a positive correlation of PAC with VF% (r = 0.377, P < 0.001) and VFA (r = 0.443, P < 0.001). The correlation was not evident in patients with APA.

Conclusions

This study revealed a relationship between visceral adipose tissue and aldosterone production only in patients with IHA.