Outcome of surgery for primary hyperaldosteronism

Performance evaluation of scoring systems for predicting post-operative hypertension cure in primary aldosteronism

OBJECTIVE

Hypertension cure following adrenalectomy in unilateral primary aldosteronism is not guaranteed. Its likelihood is associated with pre-operative parameters, which have been variably combined in six different predictive scoring systems. The relative performance of these systems is currently unknown. The objective of this work was to identify the best performing scoring system for predicting hypertension cure following adrenalectomy for primary aldosteronism.

DESIGN

Retrospective analysis in a single tertiary referral centre.

PATIENTS

Eighty-seven adult patients with unilateral primary aldosteronism who had undergone adrenalectomy between 2004 and 2018 for whom complete data sets were available to calculate all scoring systems.

MEASUREMENTS

Prediction of hypertension cure by each of the six scoring systems.

RESULTS

Hypertension cure was achieved in 36/87 (41.4%) patients within the first post-operative year, which fell to 18/71 (25.4%) patients at final follow-up (median 53 months, P = .002). Analysis of receiver operating characteristic area under the curves for the different scoring systems identified a difference in performance at early, but not late, follow-up. For all systems, the area under the curve was lower at early compared with late follow-up and compared to performance in the cohorts in which they were originally defined.

CONCLUSIONS

No single scoring system performed significantly better than all others when applied in our cohort, although two did display particular advantages. It remains to be determined how best such scoring systems can be incorporated into the routine clinical care of patients with PA.

Surgical treatment outcome of primary aldosteronism assessed using new modified diagnostic tests

PURPOSE

Primary aldosteronism (PA) is the most frequent type of endocrine hypertension. In our previous studies, we introduced two modified diagnostic tests for PA, the post-dexamethasone saline infusion test (DSIT) and the overnight dexamethasone, captopril, and valsartan test (DCVT). In this study, we aimed to validate both tests in respect to the biochemical and clinical response of a cohort of hypertensive patients in pre- and post-surgical setting.

METHODS

We retrospectively studied 41 hypertensive patients (16 males), with a median (IQR, range) age of 50 (16, 35-74) years and positive histology for adrenal adenoma. Preoperatively, all patients had a single adenoma on CT and a diagnosis of PA with either DSIT or DCVT. The defined daily dose (DDD) of hypertensive drugs was assessed pre- and postoperatively. DSIT or DCVT and basal ARR were reassessed postoperatively.

RESULTS

Two of the 41 patients failed to suppress aldosterone post-surgery, leading to a post-adrenalectomy biochemical cure rate of 95%, while blood pressure was improved in 36 patients, leading to a clinical cure rate of 88% as assessed by the DDD methodology.

CONCLUSIONS

The present study was a proof-of-concept process to validate two modified diagnostic tests for PA in clinical practice. These tests, used to diagnose a group of patients with PA, successfully assessed their biochemical cure post-adrenalectomy at rates similar to those reported in the literature.

Trends in blood pressure-related outcomes after adrenalectomy in patients with primary aldosteronism: A systematic review

BACKGROUND

Decrease in blood pressure (BP) is the major goal of adrenalectomy for primary aldosteronism. Nevertheless, the optimal timing to assess these outcomes and the needed duration of follow-up are uncertain. We systematically reviewed the literature regarding trends in BP-related outcomes during follow-up after adrenalectomy.

METHODS

A systematic literature search of medical literature from PubMed, Embase and the Cochrane Library regarding BP-related outcomes (i.e. cure of hypertension rates, BP and antihypertensives) was performed. The Quality In Prognosis Studies risk of bias tool was used.

RESULTS

Of the 2057 identified records, 13 articles met the inclusion criteria. Overall study quality was low. In multiple studies, the biggest decrease in BP was shown within the first month(s) after adrenalectomy and afterwards BP often remained stable during long-term follow-up.

CONCLUSIONS

Based on the available studies one might suggest that long follow-up is unnecessary, since outcomes seem to stabilize within the first months.

Arterial Stiffness Is Associated with Clinical Outcome and Cardiorenal Injury in Lateralized Primary Aldosteronism

CONTEXT

The association between arterial stiffness and clinical outcome in lateralized primary aldosteronism (PA) patients after adrenalectomy has not been clearly identified.

OBJECTIVE

We hypothesized that arterial stiffness estimated by brachial-ankle pulse wave velocity (baPWV) before adrenalectomy was associated with the clinical outcomes and cardiorenal injury in lateralized PA patients after adrenalectomy.

DESIGN AND PATIENTS

We designed a retrospective observational cohort study. We collected lateralized PA patients who had undergone adrenalectomy between 2013 and 2016 from the Taiwan Primary Aldosteronism Investigation database. The primary outcome was achieving complete clinical success at 1 year after adrenalectomy. The secondary outcome was estimated glomerular filtration rate declining over 20% and improved left ventricular mass index.

RESULTS

We enrolled 221 patients with lateralized PA (50.7% men; mean age, 51.9 years), of whom 101 patients (45.7%) achieved complete clinical success at the 1-year follow-up assessment after adrenalectomy. Lower baPWV before adrenalectomy (odds ratio = 0.998; 95% confidence interval, 0.996-0.999; P = 0.003) correlated with higher likelihood of complete clinical success by multivariate logistic regression analysis. Multifactorial adjusted generalized additive model demonstrated that preoperative baPWV<1600 cm/sec was significantly associated with complete cure of hypertension. In addition, higher preoperative baPWV was associated with renal function decline and less left ventricular mass regression after adrenalectomy in lateralized PA patients during the follow-up period.

CONCLUSIONS

Our study demonstrated that the preoperative severe arterial stiffness was associated with absent complete clinical success in lateralized PA patients after adrenalectomy, and this effect may contribute to cardiorenal injury, which at least partially explains kidney function deterioration and lessened regression of heart mass.

Basal Plasma Aldosterone Concentration Predicts Therapeutic Outcomes in Primary Aldosteronism

Purpose

Normal basal plasma aldosterone concentration (PAC) reflects mild aldosterone excess compared to high basal PAC. We previously reported lower risk for cardiovascular and cerebrovascular events in patients with primary aldosteronism (PA) and normal basal PAC (nPA) than in those with high basal PAC (hPA). However, the differences in therapeutic outcomes between nPA and hPA are unclear. The aim of this multi-institutional, retrospective cohort study was to determine the clinical significance of nPA to therapeutic outcomes, including adrenalectomy (ADX) and treatment with mineralocorticoid receptor antagonists (MRAs).

Methods

A total of 1146 patients with PA who were diagnosed and underwent adrenal venous sampling (AVS) between January 2006 and October 2016 were enrolled. The clinical parameters at baseline and after ADX or treatment with MRA were compared between the nPA and hPA groups.

Results

Significantly higher rates of absent clinical success (36.6 vs. 21.9%, P = 0.01) and absent biochemical success (26.4 vs. 5.2%, P < 0.01) were found for the nPA group than for the hPA group, respectively. Logistic regression analysis identified baseline PAC as a significant independent predictor of absent clinical success of ADX and MRAs.

Conclusions

Plasma aldosterone concentration at baseline was a significant and independent predictor of absent clinical success of ADX and MRA. Mineralocorticoid receptor antagonist treatment appeared to be a better therapeutic choice than ADX in the nPA group.

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.

Body mass index and contralateral ratio predict outcome following unilateral adrenalectomy in primary aldosteronism

The effect of unilateral adrenalectomy on blood pressure (BP) outcome in primary aldosteronism (PA) is diverse. Therefore, we sought to investigate the preoperative factors contributing to postoperative BP outcome. Data for 96 PA patients who underwent unilateral adrenalectomy at our institution from January 2000 to February 2015 were retrospectively collected. Based on postoperative BP after a 12-month follow-up period, the patients were categorized into two groups: cured (C) (<140/90 mm Hg with no antihypertensive drug) and not cured (NC) (if not normotensive). Patient demographics, blood and urine data, data of loading tests and adrenal vein sampling were evaluated. In all, 46 patients were categorized as C and 50 patients as NC. There were significantly more males in the NC group. Age, body mass index (BMI), number of antihypertensive drugs prescribed, serum uric acid concentration and contralateral ratio (CR) after adrenocorticotropic hormone stimulation were significantly higher in the NC group. In the multivariate model, BMI and CR significantly correlated with resolution outcome. The optimal cutoff values were 23.3 kg m^-2 for BMI and 0.5 for CR, and when both parameters were used as predictors, the most optimal cutoff values for BMI and CR were 25.2 kg m^-2 and 0.1, respectively. BMI and CR significantly correlated with BP outcome after adrenalectomy. To our knowledge, this is the first report to show that in addition to BMI, CR is a factor in postoperative BP outcome and to determine the optimal cutoff values of BMI and CR and calculate their sensitivities and specificities.

Hypertension outcomes of adrenalectomy in patients with primary aldosteronism: a systematic review and meta-analysis

BACKGROUND

The hypertension cure rate of unilateral adrenalectomy in primary aldosteronism (PA) patients varies widely in existing studies.

METHODS

We conducted an observational meta-analysis to summarize the pooled hypertension cure rate of unilateral adrenalectomy in PA patients. Comprehensive electronic searches of PubMed, Embase, Cochrane, China National Knowledge Internet (CNKI), WanFang, SinoMed and Chongqing VIP databases were performed from initial state to May 20, 2016. We manually selected eligible studies from references in accordance with the inclusion criteria. The pooled hypertension cure rate of unilateral adrenalectomy in PA patients was calculated using the DerSimonian-Laird method to produce a random-effects model.

RESULTS

Forty-three studies comprising approximately 4000 PA patients were included. The pooled hypertension cure rate was 50.6% (95% CI: 42.9-58.2%) for unilateral adrenalectomy in PA. Subgroup analyses showed that the hypertension cure rate was 61.3% (95% CI: 49.4-73.3%) in Chinese studies and 43.7% (95% CI: 38.0-49.4%) for other countries. Furthermore, the hypertension cure rate at 6-month follow-up was 53.3% (95% CI: 36.0-70.5%) and 49.6% (95% CI: 40.9-58.3%) for follow-up exceeding 6 months. The pooled hypertension cure rate was 50.9% (95% CI: 40.5-61.3%) from 2001 to 2010 and 50.2% (95% CI: 39.0-61.5%) from 2011 to 2016.

CONCLUSIONS

The hypertension cure rate for unilateral adrenalectomy in PA is not optimal. Large clinical trials are required to verify the utility of potential preoperative predictors in developing a novel and effective prediction model.

Outcomes after adrenalectomy for unilateral primary aldosteronism: an international consensus on outcome measures and analysis of remission rates in an international cohort

BACKGROUND

Although unilateral primary aldosteronism is the most common surgically correctable cause of hypertension, no standard criteria exist to classify surgical outcomes. We aimed to create consensus criteria for clinical and biochemical outcomes and follow-up of adrenalectomy for unilateral primary aldosteronism and apply these criteria to an international cohort to analyse the frequency of remission and identify preoperative determinants of successful outcome.

METHODS

The Primary Aldosteronism Surgical Outcome (PASO) study was an international project to develop consensus criteria for outcomes and follow-up of adrenalectomy for unilateral primary aldosteronism. An international panel of 31 experts from 28 centres, including six endocrine surgeons, used the Delphi method to reach consensus. We then retrospectively analysed follow-up data from prospective cohorts for outcome assessment of patients diagnosed with unilateral primary aldosteronism by adrenal venous sampling who had undergone a total adrenalectomy, consecutively included from 12 referral centres in nine countries. On the basis of standardised criteria, we determined the proportions of patients achieving complete, partial, or absent clinical and biochemical success in accordance with the consensus. We then used logistic regression analyses to identify preoperative factors associated with clinical and biochemical outcomes.

FINDINGS

Consensus was reached for criteria for six outcomes (complete, partial, and absent success of clinical and biochemical outcomes) based on blood pressure, use of antihypertensive drugs, plasma potassium and aldosterone concentrations, and plasma renin concentrations or activities. Consensus was also reached for two recommendations for the timing of follow-up assessment. For the international cohort analysis, we analysed clinical data from 705 patients recruited between 1994 and 2015, of whom 699 also had biochemical data. Complete clinical success was achieved in 259 (37%) of 705 patients, with a wide variance (range 17-62), and partial clinical success in an additional 334 (47%, range 35-66); complete biochemical success was seen in 656 (94%, 83-100) of 699 patients. Female patients had a higher likelihood of complete clinical success (odds ratio [OR] 2·25, 95% CI 1·40-3·62; p=0·001) and clinical benefit (complete plus partial clinical success; OR 2·89, 1·49-5·59; p=0·002) than male patients. Younger patients had a higher likelihood of complete clinical success (OR 0·95 per extra year, 0·93-0·98; p<0·001) and clinical benefit (OR 0·95 per extra year, 0·92-0·98; p=0·004). Higher levels of preoperative medication were associated with lower levels of complete clinical success (OR 0·80 per unit increase, 0·70-0·90; p<0·001).

INTERPRETATION

These standardised outcome criteria are relevant for the assessment of the success of surgical treatment in individual patients and will allow the comparison of outcome data in future studies. The variable baseline clinical characteristics of our international cohort contributed to wide variation in clinical outcomes. Most patients derive clinical benefit from adrenalectomy, with younger patients and female patients more likely to have a favourable surgical outcome. Screening for primary aldosteronism should nonetheless be done in every individual fulfilling US Endocrine Society guideline criteria because biochemical success without clinical success is by itself clinically important and older women and men can also derive post-operative clinical benefit.

FUNDING

European Research Council; European Union's Horizon 2020; Else Kröner-Fresenius Stiftung; Netherlands Organisation for Health Research and Development-Medical Sciences; Japanese Ministry of Health, Labour and Welfare; Ministry of Health, Slovenia; US National Institutes of Health; and CONICYT-FONDECYT (Chile).

Radiofrequency ablation compared with laparoscopic adrenalectomy for aldosterone-producing adenoma

BACKGROUND

Radiofrequency ablation (RFA) is an emerging treatment for primary aldosteronism owing to aldosterone-producing adenoma. Whether RFA could be an alternative treatment to laparoscopic adrenalectomy is unknown.

METHODS

This was a retrospective comparative study in patients with aldosterone-producing adenoma undergoing either laparoscopic adrenalectomy or CT-guided percutaneous RFA between 2004 and 2012. Short-term outcomes and long-term resolution rates of primary aldosteronism (normalized aldosterone to renin ratio), hypokalaemia and hypertension (BP lower than 140/90 mmHg without antihypertensive medical therapy) were evaluated.

RESULTS

Some 63 patients were included, 27 in the laparoscopic adrenalectomy group and 36 in the RFA group. RFA was associated with shorter duration of operation (median 12 versus 124 min; P < 0·001), shorter hospital stay (2 versus 4 days; P < 0·001), lower analgesic requirements (13 of 36 versus 23 of 27 patients; P < 0·001) and earlier resumption of work (median 4 versus 14 days; P = 0·006). Morbidity rates were similar in the two groups. With median follow-up of 5·7 (range 1·9-10·6) years, resolution of primary aldosteronism was seen in 33 of 36 patients treated with RFA and all 27 patients who had laparoscopic adrenalectomy (P = 0·180). Hypertension was resolved less frequently after treatment with RFA compared with laparoscopic adrenalectomy (13 of 36 versus 19 of 27 patients; P = 0·007). Hypokalaemia was resolved in all patients.

CONCLUSION

For patients with aldosterone-producing adenoma the efficacy of resolution of primary aldosteronism and hypertension was inferior after treatment with RFA compared with laparoscopic adrenalectomy.

Diagnostic criteria for adrenal venous sampling

PURPOSE OF REVIEW

Primary aldosteronism accounts for 3 to 5% of all hypertension cases. Unilateral aldosterone hypersecretion can be treated with adrenalectomy. Guidelines for primary aldosteronism management recommend adrenal vein sampling (AVS) to ascertain unilateral primary aldosteronism before surgery. Many different protocols are used to perform AVS and for the interpretation of its results, but without hard evidence of why one should be given preference. Experts have proposed recommendations to guide clinical practice and the grounds for future research to address this situation.

RECENT FINDINGS

Proper patient preparation is a prerequisite for interpretable results. New trends are emerging to improve adequate cannulation of adrenal veins including: training of a limited number of dedicated radiologists, contrast computed tomography of adrenal veins before or during AVS, and rapid assays to measure cortisol concentrations during AVS. Cosyntropin stimulation is performed in several centers to avoid the variability of cortisol secretion during AVS, but whether this improves diagnostic performance is unknown.

SUMMARY

Better markers of adequate catheter placement are currently under investigation, including other adrenal steroids and metanephrines. Innovative strategies for interpreting partially failed AVS are also being developed. Other approaches to ascertain primary aldosteronism subtype will be necessary because of limited patient access to AVS.

Implication of aortic calcification on persistent hypertension after laparoscopic adrenalectomy in patients with primary aldosteronism

OBJECTIVES

To identify risk factors, including aortic calcification, for persistent hypertension in primary aldosteronism patients undergoing laparoscopic adrenalectomy.

METHODS

Between October 2000 and October 2015, we carried out 101 consecutive laparoscopic adrenalectomies for unilateral primary aldosteronism. Of these, 95 cases with at least 1 year of postoperative follow up were included. These were divided into two study groups based on whether they had normal blood pressure without antihypertensive medications (resolved group) or still required medications (unresolved group) at 1 year after surgery. Variables included age, sex, body mass index, history of hypertension, dosage of antihypertensive medication score, presence of type 2 diabetes, subclinical Cushing syndrome, preoperative renal function, aldosteronoma resolution score and abdominal calcification index. Univariate and multivariate logistic regression analyses were used to assess independent risk factors for persistent hypertension 1 year after surgery.

RESULTS

The complete resolution of hypertension without antihypertensive medication 1 year after adrenalectomy was 36 out of 95 (38%). The preoperative antihypertensive medication score, systolic blood pressure and abdominal calcification index were significantly higher, and the aldosteronoma resolution score were significantly lower in the unresolved group than in the resolved group. Using multivariate logistic regression analysis, independent risk factors significantly correlating with persistent hypertension 1 year after surgery were aldosteronoma resolution score and abdominal calcification index.

CONCLUSIONS

Laparoscopic adrenalectomy for primary aldosteronism is effective in improving blood pressure and reducing the need for antihypertensive medications. Aldosteronoma resolution score and abdominal calcification index represent potential independent risk factors for persistent hypertension 1 year after surgery.

Importance of contralateral aldosterone suppression during adrenal vein sampling in the subtype evaluation of primary aldosteronism

OBJECTIVES

Adrenal vein sampling (AVS) is the standard criterion for the subtype diagnosis in primary aldosteronism (PA). Although lateralized index (LI) ≥4 after cosyntropin stimulation is the commonly recommended cut-off for unilateral aldosterone hypersecretion, many of the referral centres in the world use LI cut-off of <4 without sufficient evidence for its diagnostic accuracy.

AIM

The aim of the study was to establish the diagnostic significance of contralateral (CL) aldosterone suppression for the subtype diagnosis in patients with LI <4 in AVS.

DESIGN AND PATIENTS

A retrospective multicentre study was conducted in Japan. Of 124 PA patients subjected to unilateral adrenalectomy after successful AVS with cosyntropin administration, 29 patients with LI < 4 were included in the study. The patients were divided into Group A with CL suppression (n = 16) and Group B (n = 13) without CL suppression. Three outcome indices were assessed after 6 months postoperatively: normalization/significant improvement of hypertension, normalization of the aldosterone to renin ratio (ARR) and normalization of hypokalaemia.

RESULTS

The normalization/significant improvement of hypertension was 81% in Group A and 54% in Group B (P = 0·2). The normalization of ARR was 100% in Group A and 46% in Group B (P = 0·004). Hypokalaemia was normalized in all patients of both groups. The overall cure rate of PA based on meeting all the three criteria was 81% in Group A and 31% in Group B (P = 0·01).

CONCLUSIONS

In patients with PA, where the LI is <4 on AVS, CL suppression of aldosterone is an accurate predictor of a unilateral source of aldosterone excess. CL suppression data should be interpreted in conjunction with computed tomographic adrenal imaging findings to guide surgical management.

Development of a novel nomogram to predict hypertension cure after laparoscopic adrenalectomy in patients with primary aldosteronism

BACKGROUND

Primary aldosteronism is the most common curable cause of secondary hypertension. Despite resection, however, many patients with primary aldosteronism continue to require antihypertensive drugs to control their blood pressure. Although many patients with primary aldosteronism want to know the postoperative probability of hypertension cure before surgery, there are no predictive models calculating its probability. We therefore developed a nomogram to predict hypertension cure in patients with primary aldosteronism after laparoscopic adrenalectomy.

METHODS

We retrospectively surveyed 132 Japanese patients with primary aldosteronism who were treated by unilateral laparoscopic adrenalectomy. Hypertension cure was defined as normal blood pressure (<140/90 mmHg) without antihypertensive drugs 6 months postoperatively. We developed a novel nomogram that postoperatively predicted cured hypertension in 105 (80 %) randomly selected patients and validated it with the remaining 27 (20 %).

RESULTS

At 6 months, blood pressure had normalized in 42 % of patients without antihypertensive drugs. Duration of hypertension, preoperative number of antihypertensive drug classes, age, and sex were incorporated into a novel nomogram as independent predictors of hypertension cure. The value of the area under the receiver operating characteristics curve for this nomogram was 0.83-which was significantly higher than that of the Aldosteronoma Resolution Score-on internal validation.

CONCLUSIONS

We developed the first nomogram that can accurately predict postoperative hypertension cure in patients with primary aldosteronism. This nomogram can help clinicians calculate the probability of postoperative hypertension cure in patients with primary aldosteronism and objectively inform them of their hypertension outcome before laparoscopic adrenalectomy.

Aldosteronoma resolution score predicts long-term resolution of hypertension

BACKGROUND

The Aldosteronoma Resolution Score (ARS) takes into consideration four, readily available, preoperative clinical parameters in predicting the likelihood of resolution of hypertension in patients 6 months after undergoing unilateral adrenalectomy for aldosterone-producing adenoma (APA). We sought to determine the durability of this predictive model after 1 year.

METHODS

Sixty patients who underwent unilateral adrenalectomy for APA at a single institution between 2004 and 2013 were reviewed retrospectively. Patients who were normotensive without any antihypertensive medication requirement at greater than 1-year follow-up were considered to have complete resolution of hypertension.

RESULTS

Forty-seven patients had data available for analysis. Median follow-up was 1,135 days (371-3,202). Forty-five percent of patients had complete resolution, 45% had improvement, and 10% had no improvement in hypertension. Applying the ARS, we found there was complete resolution of hypertension in 73% of patients with ARS 4-5, 53% of patients with ARS 2-3, and 24% of patients with ARS 0-1 compared with 75% (P = .9), 46% (P = .66), and 28% (P = .76), respectively, in the original cohort used to create the ARS.

CONCLUSION

Most patients (90%) have long-term improvement or complete resolution of hypertension after unilateral adrenalectomy for APA. The ARS predicts accurately a patient's likelihood of complete resolution of hypertension beyond 1 year.

High-probability features of primary aldosteronism may obviate the need for confirmatory testing without increasing false-positive diagnoses

This retrospective review examined all primary aldosteronism (PA) adrenal vein sampling (AVS), diagnoses, and outcomes from an endocrine hypertension unit where confirmatory testing was abandoned in 2005 to determine the potential rate of false-positive diagnoses. Patients with outcome-verified PA (surgical patients) were compared with patients with high-probability PA (nonsurgical but high aldosterone-renin ratio, imaging abnormalities, and/or hypokalemia) or possible PA (nonsurgical, no features besides mild elevation of aldosterone-renin ratio, a potential false diagnosis of PA). Of 83 patients, 58% had unilateral PA and 42% had bilateral aldosteronism. Less than 3% of the cohort showed bilateral aldosteronism without hypokalemia or computed tomographic findings, potentially representing the false-positive PA diagnosis rate with omission of confirmatory tests in this population. In a hypertension referral unit enriched in high-probability PA cases and where high AVS success is achieved, omission of a PA confirmatory test yields a high rate of surgical diagnosis with few potential false-positive diagnoses.

Management of hypertension in primary aldosteronism

Hypertension causes significant morbidity and mortality worldwide, owing to its deleterious effects on the cardiovascular and renal systems. Primary hyperaldosteronism (PA) is the most common cause of reversible hypertension, affecting 5%-18% of adults with hypertension. PA is estimated to result from bilateral adrenal hyperplasia in two-thirds of patients, and from unilateral aldosterone-secreting adenoma in approximately one-third. Suspected cases are initially screened by measurement of the plasma aldosterone-renin-ratio, and may be confirmed by additional noninvasive tests. Localization of aldostosterone hypersecretion is then determined by computed tomography imaging, and in selective cases with adrenal vein sampling. Solitary adenomas are managed by laparoscopic or robotic resection, while bilateral hyperplasia is treated with mineralocorticoid antagonists. Biochemical cure following adrenalectomy occurs in 99% of patients, and hemodynamic improvement is seen in over 90%, prompting a reduction in quantity of anti-hypertensive medications in most patients. End-organ damage secondary to hypertension and excess aldosterone is significantly improved by both surgical and medical treatment, as manifested by decreased left ventricular hypertrophy, arterial stiffness, and proteinuria, highlighting the importance of proper diagnosis and treatment of primary hyperaldosteronism. Although numerous independent predictors of resolution of hypertension after adrenalectomy for unilateral adenomas have been described, the Aldosteronoma Resolution Score is a validated multifactorial model convenient for use in daily clinical practice.

Hyperaldosteronism: diagnosis, lateralization, and treatment

Primary hyperaldosteronism is an important and commonly unrecognized secondary cause of hypertension. This article provides an overview of the current literature with respect to screening, diagnosis, and lateralization. Selection and outcomes of medical and surgical treatment are discussed.

Prognostic value of semiquantification NP-59 SPECT/CT in primary aldosteronism patients after adrenalectomy

PURPOSE

Primary aldosteronism (PA), characterized by an excessive production of aldosterone, affects 5-13 % of patients with hypertension. Accurate strategies are needed for the timely diagnosis of PA to allow curability and prevention of excessive cardiovascular events and related damage. This study aimed to evaluate the usefulness of semiquantification of (131)I-6β-iodomethyl-norcholesterol (NP-59) single photon emission computed tomography (SPECT)/CT in differentiating aldosterone-producing adenoma (APA) from idiopathic adrenal hyperplasia (IAH) and in predicting clinical outcomes after adrenalectomy.

METHODS

We retrospectively reviewed 49 PA patients who had undergone adrenalectomy after NP-59 SPECT/CT within 1 year. A conventional visual scale (VS) and two semiquantitative parameters generated from SPECT/CT, adrenal to liver ratio (ALR) and lesion to contralateral ratio of bilateral adrenal glands (CON), with cutoff values calculated by receiver-operating characteristic (ROC) analysis, were compared with pathology results and postsurgical outcomes to determine the accuracy.

RESULTS

An ALR cutoff of 1.84 and a CON cutoff of 1.15 showed an ability to distinguish adenoma from hyperplasia similar to VS (p = 0.2592 and 0.1908, respectively). An ALR cutoff of 2.28 and a CON cutoff of 1.11 yielded the highest sensitivity and specificity to predict postsurgical outcomes, and an ALR of 2.28 had an ability superior to VS (p = 0.0215), while a CON of 1.11 did not (p = 0.1015). Patients with either ALR or CON greater than the cutoff had a high probability of positive postsurgical outcomes (n = 36/38), while patients with both ALR and CON less than the cutoff had a low probability of positive postsurgical outcomes (n = 2/11).

CONCLUSION

Semiquantification of NP-59 scintigraphy has an ability similar to VS in differentiating APA from IAH, but an excellent ability to predict postsurgical outcomes of adrenalectomy. An ALR or CON greater than the cutoff strongly suggests benefits from adrenalectomy, and both ALR and CON less than the cutoff implies a reduced chance of improvement in postsurgical outcome.

The vascular surgeon's experience with adrenal venous sampling for the diagnosis of primary hyperaldosteronism

BACKGROUND

Adrenal venous sampling (AVS) is used to distinguish between bilateral idiopathic hyperplasia and a functional adrenal tumor in patients with hyperaldosteronism. Successful sampling from both adrenal veins is necessary for lateralization and may require more than 1 procedure. AVS has traditionally been performed by interventional radiologists; however, our goal was to examine the outcomes when performed by a vascular surgeon.

METHODS

All patients with a diagnosis of hyperaldosteronism were referred for AVS regardless of imaging findings. Cortisol and aldosterone levels were measured in blood samples from both adrenal veins. Postoperative analysis of intraoperative laboratory values before and after cosyntropin administration determined successful cannulation and sampling of each vein.

RESULTS

Between 2007 and 2012, 53 patients underwent AVS by one vascular surgeon. The average age was 54 and 63% were men. Our success rate increased with experience, because during the earlier years (2007-2010) primary and secondary success rates were 58% and 68%, respectively compared with later years (2011-2012) when primary and secondary success rates were 82% and 95%, respectively (P<0.05). Results of AVS altered localization of disease compared with what had been anticipated based on preoperative imaging and thus influenced surgical decision making in 47% of cases.

CONCLUSIONS

AVS is an important procedure in the work up of hyperaldosteronism to help identify and localize metabolically active tumors. It is an additional area in medicine where a vascular surgeon can lend expertise. Success with the procedure improves with experience and should be performed by high volume surgeons.

A marked proportional rise in IVC aldosterone following cosyntropin administration during AVS is a signal to the presence of adrenal hyperplasia in primary aldosteronism

We hypothesized aldosteronoma responsiveness to cosyntropin may be a characterizing feature that could be determined in addition to standard adrenal vein sampling (AVS) data. We reviewed an AVS database from June 2005 to October 2011 including 65 patients with confirmed primary aldosteronism (PA) who underwent AVS and, if applicable, unilateral adrenalectomy. Patients were divided into confirmed lateralized and non-lateralized groups and subgrouped by histology. Plasma aldosterone in inferior vena cava (IVC) pre- and post-cosyntropin infusion during AVS was measured. Peak aldosterone and proportional change was compared between groups. Baseline and peak IVC aldosterone was higher in lateralized patients but incremental aldosterone rise was much greater in subjects with bilateral hyperplasia. From receiver operator characteristics (ROC) analysis, the optimized diagnostic cut point of peak IVC aldosterone of >649 pmol l(-1) would have a sensitivity of 94% for surgical disease although specificity of just 59%. A 250% increase in IVC aldosterone following cosyntropin would be specific enough to exclude 87% of surgical/lateralized disease. These diagnostic capabilities are similar to other results with non-AVS tests performed for diagnosis of lateralization. Although not specific enough to replace standard AVS interpretation, a marked IVC aldosterone increase after cosyntropin during AVS is a useful additional test to diagnose non-lateralizing forms of PA. Such a calculation requires no additional expense or tests.

An expert consensus statement on use of adrenal vein sampling for the subtyping of primary aldosteronism

Adrenal venous sampling is recommended by current guidelines to identify surgically curable causes of hyperaldosteronism but remains markedly underused. Key factors contributing to the poor use of adrenal venous sampling include the prevailing perceptions that it is a technically challenging procedure, difficult to interpret, and can be complicated by adrenal vein rupture. In addition, the lack of uniformly accepted standards for the performance of adrenal venous sampling contributes to its limited use. Hence, an international panel of experts working at major referral centers was assembled to provide updated advice on how to perform and interpret adrenal venous sampling. To this end, they were asked to use the PICO (Patient or Problem, Intervention, Control or comparison, Outcome) strategy to gather relevant information from the literature and to rely on their own experience. The level of evidence/recommendation was provided according to American Heart Association gradings whenever possible. A consensus was reached on several key issues, including the selection and preparation of the patients for adrenal venous sampling, the procedure for its optimal performance, and the interpretation of its results for diagnostic purposes even in the most challenging cases.

A clinical prediction score to diagnose unilateral primary aldosteronism

CONTEXT

Adrenal venous sampling is recommended to assess whether aldosterone hypersecretion is lateralized in patients with primary aldosteronism. However, this procedure is invasive, poorly standardized, and not widely available.

OBJECTIVE

Our goal was to identify patients' characteristics that can predict unilateral aldosterone hypersecretion in some patients who could hence bypass adrenal venous sampling before surgery.

DESIGN AND SETTING

A cross-sectional diagnostic study was performed from February 2009 to July 2010 at a single center specialized in hypertension care.

PATIENTS

A total of 101 consecutive patients with primary aldosteronism who underwent adrenal venous sampling participated in the study. The autonomy of aldosterone hypersecretion was assessed with the saline infusion test.

INTERVENTION

Adrenal venous sampling was performed without ACTH infusion but with simultaneous bilateral sampling.

MAIN OUTCOME MEASURES

Variables independently associated with a lateralized adrenal venous sampling in multivariate logistic regression were used to derive a clinical prediction rule.

RESULTS

Adrenal venous sampling was successful in 87 patients and lateralized in 49. All 26 patients with a typical Conn's adenoma plus serum potassium of less than 3.5 mmol/liter or estimated glomerular filtration rate of at least 100 ml/min/1.73 m2 (or both) had unilateral primary aldosteronism; this rule had 100% specificity (95% confidence interval, 91-100) and 53% sensitivity (95% confidence interval, 38-68).

CONCLUSIONS

If our results are validated on an independent sample, adrenal venous sampling could be omitted before surgery in patients with a typical Conn's adenoma if they meet at least one of two supplementary biochemical characteristics (serum potassium<3.5 mmol/liter or estimated glomerular filtration rate ≥100 ml/min/1.73 m2).

Blood pressure and medication changes following adrenalectomy for unilateral primary aldosteronism: a follow-up study

OBJECTIVE

Adrenalectomy for unilateral primary aldosteronism cures hypertension in less than 50% of patients, but improvement is observed in most of the remaining ones. Our goal was to quantify the blood pressure (BP) decrease adjusted for medication changes following adrenalectomy and to identify preoperative predictors of this outcome.

METHODS

We analyzed simultaneous changes in BP and medication by reviewing the records of 156 consecutive patients who had undergone adrenalectomy for unilateral primary aldosteronism in one center between 2001 and 2009 for whom postoperative follow-up data were available.

RESULTS

Median [interquartile range] baseline SBP was 149 [135-160] mmHg on drugs from two [1-3] different classes. After adrenalectomy, SBP decreased by 21 [5-31] mmHg and the number of drug classes administered, by one [0-2]. The decrease in SBP, adjusted for the change in the number of drug classes, was 26 [14-36] mmHg. Each drug class dropped after surgery was equivalent to a 5 mmHg SBP decrease. Patients with higher preoperative BP or serum sodium levels experienced a greater BP decrease after adrenalectomy. Adrenalectomy cured hypertension in 68 (44%) patients. Hypertension was less likely to be cured in patients with a longer history of hypertension, higher preoperative BP levels, larger number of drug classes, or lower urinary aldosterone levels.

CONCLUSION

Although patients with severe hypertension are likely to derive considerable benefits from adrenalectomy in terms of BP or treatment reduction, they should be warned that hypertension cure is unlikely.