Time course and factors predicting arterial stiffness reversal in patients with aldosterone-producing adenoma after adrenalectomy: prospective study of 102 patients

The mTOR-inhibitor everolimus reduces hypervolemia in patients with primary aldosteronism

BACKGROUND

We recently showed in a proof-of-concept study that treating individuals with primary aldosteronism with the mTOR-inhibitor everolimus decreases home blood pressure and renin suppression overall, and markedly reduces aldosterone levels in a subset of individuals. Based on these findings, the question arose whether the effects of everolimus were also mediated via aldosterone-independent mechanisms. Here, we undertook an exploratory, secondary analysis of above-mentioned study to comprehensively investigate how everolimus impacted the hemodynamic status of the study participants, which in turn could elucidate these mechanisms.

METHODS

Hemodynamic parameters were measured in study participants with primary aldosteronism at baseline, after treatment with everolimus 0.75 mg orally twice daily for 2 weeks and after a 2-week wash-out. Of the 14 participants, 10 participants had complete data sets for peripheral and central blood pressure, heart rate and pulse wave velocity, and 7 participants had complete data sets for cardiac index, inotropic state index, left stroke work index and stroke systemic vascular resistance index that could be analyzed. Parameters were acquired by brachial oscillometry (Mobil-o-graph PWA) and thoracic electrical bioimpedance (HOTMAN® System).

RESULTS

After treatment with everolimus, peripheral (P=0.049) and central (P=0.037) diastolic blood pressure, as well as hypervolemia (P=0.008) were significantly decreased. Likewise, peripheral (P=0.073) and central systolic blood pressure (P=0.166) trended downwards.

CONCLUSIONS

Everolimus lowers central and peripheral blood pressure in individuals with primary aldosteronism, possibly by decreasing primary aldosteronism-induced hypervolemia and preload.

Recent progress in unraveling cardiovascular complications associated with primary aldosteronism: a succinct review

This comprehensive review offers a thorough exploration of recent advancements in our understanding of the intricate cardiovascular complications associated with Primary Aldosteronism (PA). PA encompasses a spectrum of conditions characterized by hypertension and excessive production of aldosterone operating independently of the renin-angiotensin system. Given its association with an elevated risk of cardiovascular and cerebrovascular complications, as well as a higher incidence of metabolic syndrome in comparison to individuals with essential hypertension (EH), an accurate diagnosis of PA is of paramount importance. This review delves into the intricate interplay between PA and cardiovascular health and focuses on the key pathophysiological mechanisms contributing to adverse cardiac outcomes. The impact of different treatment modalities on cardiovascular health is also examined, offering insights into potential therapeutic approaches. By highlighting the significance of recognizing PA as a significant contributor to cardiovascular morbidity, this review emphasizes the need for improved screening, early diagnosis, and tailored management strategies to both enhance patient care and mitigate the burden of cardiovascular diseases. The findings presented herein underscore the growing importance of PA in the context of cardiovascular medicine and emphasize the potential for translating these insights into targeted interventions to improve patient outcomes.

Synergistic effect of albuminuria on atherosclerosis in patients with primary aldosteronism

Background

Primary aldosteronism (PA) has been associated with atherosclerosis beyond the extent of essential hypertension, but the impact of albuminuria remains unknown.

Objective

To investigate the effect of concomitant albuminuria on arterial stiffness in PA.

Design

Prospective cohort study.

Methods

A prospective cohort study was conducted to evaluate the association of albuminuria (>30 mg/g in morning spot urine) with arterial stiffness, as measured non-invasively by pulse wave velocity (PWV) in patients with PA. Propensity score matching (PSM) with age, sex, diabetes, systolic and diastolic blood pressure, creatinine, potassium, number of antihypertensive medications, and hypertension history was used to balance baseline characteristics. The effects of albuminuria on PWV before and 1 year after treatment were analyzed.

Results

A total of 840 patients with PA were enrolled, of whom 243 had concomitant albuminuria. After PSM, there were no significant differences in baseline demographic parameters except alpha-blocker and spironolactone use. PWV was greater in the presence of albuminuria (p = 0.012) and positively correlated with urine albumin-creatinine ratio. Multivariable regression analysis identified albuminuria, age, body weight, systolic blood pressure, and calcium channel blocker use as independent predictors of PWV. As for treatment response, only PA patients with albuminuria showed significant improvements in PWV after PSM (p = 0.001). The magnitude of improvement in PWV increased with urine albumin-creatinine ratio and reached plateau when it exceeded 100 mg/g according to restricted cubic spline analysis.

Conclusion

Concomitant albuminuria in PA was associated with greater arterial stiffness and more substantial improvement after targeted treatment. Both the baseline and the improved extent of PWV increased in correlation with rising urine albumin-creatinine ratio levels, reaching a plateau when the urine albumin-creatinine ratio surpassed 100 mg/g.

Surgery for Primary Aldosteronism in France From 2010 to 2020 - Results from the French-Speaking Association of Endocrine Surgery (AFCE): Eurocrine Study Group

OBJECTIVE

Describe the diagnostic workup and postoperative results for patients treated by adrenalectomy for primary aldosteronism in France from 2010 to 2020.

BACKGROUND

Primary aldosteronism (PA) is the underlying cause of hypertension in 6% to 18% of patients. French and international guidelines recommend CT-scan and adrenal vein sampling as part of diagnostic workup to distinguish unilateral PA amenable to surgical treatment from bilateral PA that will require lifelong antialdosterone treatment.Adrenalectomy for unilateral primary aldosteronism has been associated with complete resolution of hypertension (no antihypertensive drugs and normal ambulatory blood pressure) in about one-third of patients and complete biological success in 94% of patients.These results are mainly based on retrospective studies with short follow-up and aggregated patients from various international high-volume centers.

METHODS

Here we report results from the French-Speaking Association of Endocrine Surgery (AFCE) using the Eurocrine® Database.

RESULTS

Over 11 years, 385 patients from 10 medical centers were eligible for analysis, accounting for >40% of adrenalectomies performed in France for primary aldosteronism over the period.Preoperative workup was consistent with guidelines for 40% of patients. Complete clinical success (CCS) at the last follow-up was achieved in 32% of patients, and complete biological success was not sufficiently assessed.For patients with 2 follow-up visits, clinical results were not persistent at 1 year for one-fifth of patients.Factors associated with CCS on multivariate analysis were body mass index, duration of hypertension, and number of antihypertensive drugs.

CONCLUSIONS

These results call for an improvement in thorough preoperative workup and long-term follow-up of patients (clinical and biological) to early manage hypertension and/or PA relapse.

The effect of four weeks blood flow restricted resistance training on macro- and micro-vascular function in healthy, young men

PURPOSE

To determine the macrovascular and microvascular function responses to resistance training with blood flow restriction (BFR) compared to high-load resistance training (HLRT) control group.

METHODS

Twenty-four young, healthy men were randomly assigned to BFR or HLRT. Participants performed bilateral knee extensions and leg presses 4 days per week, for 4 weeks. For each exercise, BFR completed 3 X 10 repetitions/day at 30% of 1-repetition max (RM). The occlusive pressure was applied at 1.3 times of individual systolic blood pressure. The exercise prescription was identical for HLRT, except the intensity was set at 75% of one repetition maximum. Outcomes were measured pre-, at 2- and 4-weeks during the training period. The primary macrovascular function outcome was heart-ankle pulse wave velocity (haPWV), and the primary microvascular function outcome was tissue oxygen saturation (StO2) area under the curve (AUC) response to reactive hyperemia.

RESULTS

Knee extension and leg press 1-RM increased by 14% for both groups. There was a significant interaction effect for haPWV, decreasing - 5% (Δ-0.32 m/s, 95% confidential interval [CI] - 0.51 to - 0.12, effect size [ES] =  - 0.53) for BFR and increasing 1% (Δ0.03 m/s, 95%CI - 0.17 to 0.23, ES = 0.05) for HLRT. Similarly, there was an interaction effect for StO2 AUC, increasing 5% (Δ47%･s, 95%CI - 3.07 to 98.1, ES = 0.28) for HLRT and 17% (Δ159%･s, 95%CI 108.23-209.37, ES = 0.93) for BFR group.

CONCLUSION

The current findings suggest that BFR may improve macro- and microvascular function compared to HLRT.

Implication of MR Activity in Posttreatment Arterial Stiffness Reversal in Patients With Primary Aldosteronism

CONTEXT

Primary aldosteronism (PA) patients have a higher degree of arterial stiffness, which can be reversed after adrenalectomy.

OBJECTIVE

We aimed to compare the reversal of arterial stiffness between surgically and medically treated PA patients and to identify the predictors of effective medical treatment.

METHODS

We prospectively enrolled 445 PA patients and collected data on baseline clinical characteristics, biochemistry, blood pressure, and pulse wave velocity (PWV) before treatment and 12 months after treatment. In the mineralocorticoid receptor antagonist (MRA)-treated patients, the relationship between the change in PWV after 1 year (ΔPWV) and posttreatment renin activity was explored using the restricted cubic spline (RCS) method.

RESULTS

Of the 445 enrolled PA patients, 255 received adrenalectomy (group 1) and 190 received MRAs. In the RCS model, posttreatment plasma renin activity (PRA) 1.5 ng/mL/h was the best cutoff value. Therefore, we divided the MRA-treated patients into 2 groups: those with suppressed PRA (< 1.5 ng/mL/h, group 2), and those with unsuppressed PRA (≥ 1.5 ng/mL/h, group 3). Only group 1 and group 3 patients had a statistically significant improvement in PWV after treatment (both P < .001), whereas no significant improvement was noted in group 2 after treatment (P = .151). In analysis of variance and post hoc analysis, group 2 had a significantly lower ΔPWV than group 1 (P = .007) and group 3 (P = .031). Multivariable regression analysis of the MRA-treated PA patients identified log-transformed posttreatment PRA, age, and baseline PWV as independent factors correlated with ΔPWV.

CONCLUSION

The reversal of arterial stiffness was found in PA patients receiving adrenalectomy and in medically treated PA patients with unsuppressed PRA.

Mineralocorticoid receptor antagonist treatment improved arterial stiffness in patients with primary aldosteronism: a cohort study compared with adrenalectomy

Background

Elevated arterial stiffness in patients with primary aldosteronism (PA) can be reversed after adrenalectomy; however, the effect of medical treatment with mineralocorticoid receptor antagonist (MRAs) is unknown.

Objectives

The aim of this study was to evaluate the effect of MRAs and compare both treatment strategies on arterial stiffness in PA patients.

Design

Prospective cohort study.

Methods

We prospectively enrolled PA patients from 2006 to 2019 who received either adrenalectomy or MRA treatment (spironolactone). We compared their baseline and 1-year post-treatment biochemistry characteristics and arterial pulse wave velocity (PWV) to verify the effects of treatment and related determinant factors.

Results

A total 459 PA patients were enrolled. After 1:1 propensity score matching for age, sex and blood pressure (BP), each group had 176 patients. The major determinant factors of baseline PWV were age and baseline BP. The adrenalectomy group had greater improvements in BP, serum potassium level, plasma aldosterone concentration, and aldosterone-to-renin ratio. The MRA group had a significant improvement in PWV after 1 year of treatment (1706.2 ± 340.05 to 1613.6 ± 349.51 cm/s, p < 0.001). There were no significant differences in post-treatment PWV (p = 0.173) and improvement in PWV (p = 0.579) between the adrenalectomy and MRA groups. The determinant factors for an improvement in PWV after treatment were hypertension duration, baseline PWV, and the decrease in BP.

Conclusion

The PA patients who received medical treatment with MRAs had a significant improvement in arterial stiffness. There was no significant difference in the improvement in arterial stiffness between the two treatment strategies.

Diabetes mellitus is associated with worse baseline and less post-treatment recovery of arterial stiffness in patients with primary aldosteronism

Background:

Aldosterone excess in primary aldosteronism (PA) has been linked to insulin resistance, and diabetes mellitus has been associated with increased arterial stiffness and worse cardiovascular outcomes. However, the impact of diabetes on baseline and post-treatment arterial stiffness in patients with PA is unknown.

Methods:

This study prospectively enrolled 1071 PA patients, of whom 177 had diabetes and 894 did not. Clinical, biochemical, and brachial-ankle pulse wave velocity (baPWV) data were analyzed at baseline and 1 year after PA-specific treatment. After propensity score matching of age, sex, body mass index, systolic and diastolic blood pressure, hypertension duration, and number of antihypertensive medications, 144 patients with diabetes and 320 without diabetes were included for further analysis.

Results:

After propensity score matching, the baseline characteristics were balanced between the diabetes and nondiabetes groups except for fasting glucose, HbA1c, and lipid profiles. The patients with diabetes had significantly worse baseline baPWV compared with those without diabetes. After multivariable linear regression, the presence of diabetes mellitus remained a significant predictor of worse baseline mean baPWV (β: 46.3, 95% confidence interval: 2.9–89.7, p = 0.037). After 1 year of PA-specific treatment, only the nondiabetes group had significant recovery of mean baPWV (1661.8 ± 332.3 to 1565.0 ± 329.2 cm/s, p < 0.001; Δ = −96.8 ± 254.6 cm/s). In contrast, the diabetes group had less improvement (1771.2 ± 353.8 cm/s to 1742.0 ± 377.2 cm/s, p = 0.259; Δ = −29.2 ± 263.2 cm/s) even though the systolic and diastolic blood pressure significantly improved in both groups.

Conclusion:

The presence of diabetes mellitus in PA patients was associated with worse baseline and less post-treatment recovery of arterial stiffness.

KCNJ5 Somatic Mutation Is Associated With Higher Aortic Wall Thickness and Less Calcification in Patients With Aldosterone-Producing Adenoma

OBJECTIVE

Primary aldosteronism (PA) is the most common type of secondary hypertension, and it is associated with a higher rate of cardiovascular complications. KCNJ5 somatic mutations have recently been identified in aldosterone-producing adenoma (APA), however their influence on vascular remodeling and injury is still unclear. The aim of this study was to investigate the association between KCNJ5 somatic mutation status and vascular status.

METHODS

We enrolled 179 APA patients who had undergone adrenalectomy from a prospectively maintained database, of whom 99 had KCNJ5 somatic mutations. Preoperative clinical, biochemical and imaging data of abdominal CT, including abdominal aortic calcification (AAC) score, aortic diameter and wall thickness at levels of superior (SMA) and inferior (IMA) mesenteric arteries were analyzed.

RESULTS

After propensity score matching for age, sex, body mass index, triglycerides and low-density lipoprotein, there were 48 patients in each KCNJ5 (+) and KCNJ5 (-) group. Mutation carriers had a lower AAC score (217.3 ± 562.2 vs. 605.6 ± 1359.1, P=0.018), higher aortic wall thickness (SMA level: 2.2 ± 0.6 mm vs. 1.8 ± 0.6 mm, P=0.006; IMA level: 2.4 ± 0.6 mm vs. 1.8 ± 0.7 mm, P<0.001) than non-carriers. In multivariate analysis, KCNJ5 mutations were independently associated with AAC score (P=0.014) and aortic wall thickness (SMA level: P<0.001; IMA level: P=0.004). After adrenalectomy, mutation carriers had less aortic wall thickness progression than non-carriers (Δthickness SMA: -0.1 ± 0.8 mm vs. 0.9 ± 0.6 mm, P=0.024; IMA: -0.1 ± 0.6 mm vs. 0.8 ± 0.7 mm, P=0.04).

CONCLUSION

KCNJ5 mutation carriers had less calcification burden of the aorta, thickened aortic wall, and less wall thickness progression than non-carriers.

Heart-Ankle Pulse Wave Velocity Is Superior to Brachial-Ankle Pulse Wave Velocity in Detecting Aldosterone-Induced Arterial Stiffness

Primary aldosteronism (PA) is associated with higher arterial stiffness compared to essential hypertension (EH). However, few studies have compared different pulse wave velocity (PWV) parameters to detect aldosterone-induced arterial stiffness. In this study, we aimed to compare the sensitivity in detecting aldosterone-induced arterial stiffness between brachial-ankle PWV (baPWV) and heart-ankle PWV (haPWV). We prospectively enrolled 1006 PA patients and 983 EH patients. Detailed medical history, basic biochemistry data and two PWV measurements (baPWV and haPWV) were collected in both groups. We performed analysis on the original cohort and two propensity score matching (PSM) models (model 1 adjusted for age and sex; model 2 adjusted for age, sex, systolic and diastolic blood pressure). The DeLong test was used to compare areas under receiver operating characteristic curves (AUCs) between baPWV and haPWV to predict PA. In all models, the PA patients had significantly higher baPWV compared to the EH patients. The AUC of haPWV was greater than that of baPWV. In conclusion, haPWV seems to be a better PWV parameter than baPWV in detecting aldosterone-induced arterial stiffness.

Time-Dependent Risk of Atrial Fibrillation in Patients With Primary Aldosteronism After Medical or Surgical Treatment Initiation

[Figure: see text].

Increased risk of atrial fibrillation was reported in patients with primary aldosteronism. However, data are limited regarding the time-dependent risk of atrial fibrillation in surgically or medically treated primary aldosteronism. From the National Health Insurance Claim database in Korea (2003–2017), a total of 1418 patients with primary aldosteronism (adrenalectomy [ADX], n=755, mineralocorticoid receptor antagonist n=663) were age- and sex-matched at a 1:5 ratios to patients with essential hypertension (n=7090). Crude incidence of new onset atrial fibrillation was 2.96% in primary aldosteronism and 1.97% in essential hypertension. Because of nonproportional hazard observed in new onset atrial fibrillation, analysis time was split at 3 years. Compared with essential hypertension, risk of new onset atrial fibrillation peaked at 1 year gradually declined but remained elevated up to 3 years in overall treated primary aldosteronism (adjusted hazard ratio [aHR] 3.02; P<0.001) as well as in both ADX (aHR, 3.54; P<0.001) and mineralocorticoid receptor antagonist groups (aHR 2.27; P=0.031), which became comparable to essential hypertension afterward in both groups (ADX aHR, 0.38; P=0.102; mineralocorticoid receptor antagonist aHR, 0.60; P=0.214). Nonetheless, mineralocorticoid receptor antagonist group was associated with increased risk of nonfatal stroke (aHR, 1.21; P=0.031) compared with essential hypertension, whereas ADX was not (aHR, 1.26; P=0.288). Our results suggest the risk of new-onset atrial fibrillation remained elevated up to 3 years in treated primary aldosteronism compared with essential hypertension, which declined to comparable risk in essential hypertension thereafter. Monitoring for atrial fibrillation up to 3 years after treatment, particularly ADX, might be warranted.

Aldosterone-to-renin ratio is related to arterial stiffness when the screening criteria of primary aldosteronism are not met

Aldosterone-to-renin ratio (ARR) is a screening tool for primary aldosteronism (PA), but the significance of ARR when the PA criteria are not met remains largely unknown. In this cross-sectional study we investigated the association of ARR with haemodynamic variables in 545 normotensive and never-medicated hypertensive subjects (267 men, 278 women, age range 19-72 years) without suspicion of PA. Supine haemodynamic data was recorded using whole-body impedance cardiography and radial tonometric pulse wave analysis. In sex-adjusted quartiles of ARR, determined as serum aldosterone to plasma renin activity ratio, the mean values were 282, 504, 744 and 1467 pmol/µg of angiotensin I/h, respectively. The only difference in haemodynamic variables between the ARR quartiles was higher pulse wave velocity (PWV) in the highest quartile versus other quartiles (p = 0.004), while no differences in blood pressure (BP), heart rate, wave reflections, cardiac output or systemic vascular resistance were observed between the quartiles. In linear regression analysis with stepwise elimination, ARR was an independent explanatory factor for PWV (β = 0.146, p < 0.001, R2 of the model 0.634). In conclusion, ARR was directly and independently associated with large arterial stiffness in individuals without clinical suspicion of PA. Therefore, ARR could serve as a clinical marker of cardiovascular risk.Trial registration: ClinicalTrails.gov: NCT01742702.

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.

Left ventricular remodeling and dysfunction in primary aldosteronism

Primary aldosteronism (PA) is a common cause of secondary hypertension and is associated with worse cardiovascular outcomes. The elevated aldosterone in PA leads to left ventricular (LV) remodeling and dysfunction. In recent decades, clinical studies have demonstrated worse LV remodeling including increased LV mass and cardiac fibrosis in patients with PA compared to patients with essential hypertension. Several mechanisms may explain the process of aldosterone-induced LV remodeling, including directly profibrotic and hypertrophic effects of aldosterone on myocardium, increased reactive oxygen species and profibrotic molecules, dysregulation of extracellular matrix metabolism, endothelium dysfunction and circulatory macrophages activation. LV remodeling causes LV diastolic and systolic dysfunction, which may consequently lead to clinical complications such as heart failure, atrial fibrillation, ischemic heart disease, and other vascular events. Adequate treatment with adrenalectomy or medical therapy can improve LV remodeling and dysfunction in PA patients. In this review, we discuss the mechanisms of aldosterone-induced LV remodeling and provide an up-to-date review of clinical research about LV remodeling-related heart structural changes, cardiac dysfunction, and their clinical impacts on patients with PA.

Restoring Blood Pressure in Hypertensive Mice Fails to Fully Reverse Vascular Stiffness

Background

Hypertension is a well-established driver of vascular remodeling and stiffening. The goal of this study was to evaluate whether restoring normal blood pressure (BP) fully restores vascular stiffness toward that of normotensive controls.

Methods

C57Bl6/J male mice received angiotensin II (angII; 1 μg/kg/min) via infusion pump for 8 weeks (hypertension group: HH), angII for 4 weeks (hypertension group: H4), angII for 4 weeks followed by 4 weeks of recovery (reversal group: HN), or sham treatment (normotensive group: NN). BP, heart rate, and pulse wave velocity (PWV) were measured longitudinally. At the end of the study period, aortas were harvested for testing of vasoreactivity, passive mechanical properties, and vessel structure.

Results

The HH group exhibited a sustained increase in BP and PWV over the 8-week period (p < 0.01). In the HN group, BP and PWV increased during the 4-week angII infusion, and, though BP was restored during the 4-week recovery, PWV exhibited only partial restoration (p < 0.05). Heart rate was similar in all cohorts. Compared to NN controls, both HH and HN groups had significantly increased wall thickness (p < 0.05 HH vs. NN, p < 0.01 HN vs. NN), mucosal extracellular matrix accumulation (p < 0.0001 HH vs. NN, p < 0.05 HN vs. NN), and intralamellar distance (p < 0.001 HH vs. NN, p < 0.01 HN vs. NN). Both intact and decellularized vessels were noted to have significantly higher passive stiffness in the HH and H4 cohorts than in NN controls (p < 0.0001). However, in the HN cohort, intact vessels were only modestly stiffer than those of NN controls, and decellularized HN vessels were identical to those from the NN controls. Compared to NN controls, the HH and HN cohorts exhibited significantly diminished phenylephrine-induced contraction (p < 0.0001) and endothelium-dependent vasodilation (p < 0.05).

Conclusion

Hypertension causes a significant increase in in vivo aortic stiffness that is only partially reversible after BP normalization. Although hypertension does lead to matrix stiffening, restoration of BP restores matrix mechanics to levels similar to those of normotensive controls. Nevertheless, endothelial and vascular smooth muscle cell dysfunction persist after restoration of normotension. This dysfunction is, in part, responsible for augmented PWV after restoration of BP.

Surgery decreases the long-term incident stroke risk in patients with primary aldosteronism

BACKGROUND

Hypertension with hyperaldosteronism could be associated with stroke attributable to endothelial injury. Whether the detrimental effect of aldosterone on stroke among primary aldosteronism patients could be mitigated by administration of mineralocorticoid receptor antagonist or by reduction of aldosterone level via adrenalectomy is still inconclusive.

METHODS

Primary aldosteronism and essential hypertensive patients were enrolled in the Taiwan National Health Insurance from 1997 to 2009. We used a validated algorithm to enroll primary aldosteronism patients. We conducted a competing risk analysis, using a time-varying Cox proportional hazard model.

RESULTS

We enrolled 3,167 primary aldosteronism patients with a subgroup of 1,047 aldosterone-producing adenoma patients, and matched these with essential hypertensive controls in a 1:4 ratio. The risk of incident stroke, both ischemic and hemorrhagic, was statistically higher in primary aldosteronism patients than in their essential hypertensive control. The differences in stroke incidences between primary aldosteronism and essential hypertensive patients significantly increased as the hypertensive period lengthened. Primary aldosteronism patients who received mineralocorticoid receptor antagonist treatment had higher risk of all stroke (competing hazard ratio = 1.83, P < .001) compared with their essential hypertensive controls. In light of this, aldosterone-producing adenoma patients had a lower risk of incident stroke after adrenalectomy (competing for hazard ratio = 0.75), but a higher cumulative risk of incident stroke after mineralocorticoid receptor antagonist only (competing for hazard ratio = 1.76) than their matched essential hypertensive patients.

CONCLUSION

We observed an increased stroke risk among primary aldosteronism patients than among their matched essential hypertensive controls. A prolonged duration of hypertension was proportionate to the raised risk of stroke. Our findings emphasize the importance of aldosterone-producing adenoma benefitting from adrenalectomy in attenuating the cerebrovascular event.

Endothelial Dysfunction in Primary Aldosteronism

Primary aldosteronism (PA) is characterized by excess production of aldosterone from the adrenal glands and is the most common and treatable cause of secondary hypertension. Aldosterone is a mineralocorticoid hormone that participates in the regulation of electrolyte balance, blood pressure, and tissue remodeling. The excess of aldosterone caused by PA results in an increase in cardiovascular and cerebrovascular complications, including coronary artery disease, myocardial infarction, stroke, transient ischemic attack, and even arrhythmia and heart failure. Endothelial dysfunction is a well-established fundamental cause of cardiovascular diseases and also a predictor of worse clinical outcomes. Accumulating evidence indicates that aldosterone plays an important role in the initiation and progression of endothelial dysfunction. Several mechanisms have been shown to contribute to aldosterone-induced endothelial dysfunction, including aldosterone-mediated vascular tone dysfunction, aldosterone- and endothelium-mediated vascular inflammation, aldosterone-related atherosclerosis, and vascular remodeling. These mechanisms are activated by aldosterone through genomic and nongenomic pathways in mineralocorticoid receptor-dependent and independent manners. In addition, other cells have also been shown to participate in these mechanisms. The complex interactions among endothelium, inflammatory cells, vascular smooth muscle cells and fibroblasts are crucial for aldosterone-mediated endothelial dysregulation. In this review, we discuss the association between aldosterone and endothelial function and the complex mechanisms from a molecular aspect. Furthermore, we also review current clinical research of endothelial dysfunction in patients with PA.

Maintenance of long-term blood pressure control and vascular health by low-dose amiloride-based therapy in hyperaldosteronism

Whether aldosterone itself contributes directly to macro- or microcirculatory disease in man or to adverse cardiovascular outcomes is not fully known. We report our long-term single-practice experience in an unusual group of five patients with chronic hyperaldosteronism (HA, including three with glucocorticoid-remediable aldosteronism, GRA) treated with low-dose amiloride (a specific epithelial sodium channel [ENaC] blocker) 5-10 (mean 7) mg daily for 14-28 (mean 20) years. Except for one GRA diagnosed in infancy, all had severe resistant hypertension. In each case, BP was normalized within 1-4 weeks after starting amiloride and office BP's remained well controlled throughout the next two decades. 24-hour ambulatory BP monitoring with pulse wave analysis (cardiac output, vascular resistance, augmentation index, reflection magnitude), regional pulse wave velocities, pulse stiffening ratio, ankle-brachial index, serum creatinine, estimated glomerular filtration rate, and spot urinary albumin:creatinine ratio were measured after a mean of 18 years; all of these indicators were essentially normal. Over two additional years of observation (100 patient-years total), no cardiovascular or renal event occurred. We conclude that long-term ENaC blockade with amiloride can normalize BP and protect macro- and microvascular function in patients with HA. This suggests that either (a) putative vasculopathic effects of aldosterone are mediated via ENaC or (b) aldosterone may not play a direct role in age-dependent vasculopathic changes in humans independent of blood pressure. These findings, coupled with our literature review in both animal and human results, underscore the need for additional studies.

Long-term BP control and vascular health in patients with hyperaldosteronism treated with low-dose, amiloride-based therapy

Whether aldosterone itself contributes directly to macro- or microcirculatory disease in man or to adverse cardiovascular outcomes is not fully known. We report our long-term single-practice experience in 5 patients with chronic hyperaldosteronism (HA, including 3 with glucocorticoid remediable aldosteronism, GRA) treated with low-dose amiloride (a specific epithelial sodium channel [ENaC] blocker) 5-10 (mean 7) mg daily for 14-28 (mean 20) years. Except for 1 GRA diagnosed in infancy, all had severe resistant hypertension. In each case, BP was normal or near-normal within 1-4 weeks after starting amiloride and office BP's were well controlled for 20 years thereafter. Vascular studies and 24-hour ambulatory BP monitoring with pulse wave analysis (cardiac output, vascular resistance, augmentation index, and reflection magnitude) were assessed after a mean of 18 years as were regional pulse wave velocities, pulse stiffening ratio, ankle-brachial index, serum creatinine, estimated glomerular filtration rate, and spot urinary albumin:creatinine ratio. All indicators were completely normal in all patients after 18 years of amiloride, and none had a cardiovascular event during the 20-year mean follow-up. We conclude that long-term ENaC blockade can normalize BP and protect macro- and microvascular function in patients with HA. This suggests that (a) any vasculopathic effects of aldosterone are mediated via ENaC, not MR activation itself, and are fully preventable or reversible with ENaC blockade or (b) aldosterone may not play a major BP-independent role in human macro- and microcirculatory diseases. These and other widely divergent results in the literature underscore the need for additional studies regarding aldosterone, ENaC, and vascular disease.

Primary Aldosteronism and Cerebrovascular Diseases

As diagnostic techniques have advanced, primary aldosteronism (PA) has emerged as the most common cause of secondary hypertension. The excess of aldosterone caused by PA resulted in not only cardiovascular complications, including coronary artery disease, myocardial infarction, arrhythmia, and heart failure, but also cerebrovascular complications, such as stroke and transient ischemic attack. Moreover, PA is associated more closely with these conditions than is essential hypertension. In this review, we present up-to-date findings on the association between PA and cerebrovascular diseases.

Potential Role of Antihypertensive Medications in Preventing Excessive Arterial Stiffening

PURPOSE OF REVIEW

Increased arterial stiffness, an abnormal structural and functional change in the vascular wall, is a precursor for hypertension, coronary heart disease, stroke, and associated cardiovascular disease (CVD). The aim of this paper is to review the etiology of arterial stiffening and potential therapeutic approaches to modulate arterial fibrosis and stiffness.

RECENT FINDINGS

The Framingham Heart Study demonstrated that arterial stiffness is an independent predictor of CVD and related morbidity and mortality. Dysfunction of endothelial cells, vascular smooth muscle cells, extracellular matrix, and other functional elements of the vessel wall contribute to underlying pathophysiology of increased arterial stiffness. An activated renin-angiotensin-aldosterone system, oxidative stress, abnormal peri-vascular adipose tissue, inflammation, and increased sympathetic nervous system activity are associated with the development and progression of arterial fibrosis, stiffening, and associated CVD. In this review, we will discuss the structural and function changes and mechanisms of the vessel wall in arterial stiffness and provide potential therapeutic strategies.

Arterial stiffness and blood pressure improvement in aldosterone-producing adenoma harboring KCNJ5 mutations after adrenalectomy

The aim of this study was to show the effect of KCNJ5 mutational status on arterial stiffness in aldosterone-producing adenomas after adrenalectomy. Between February 2008 and January 2010, we prospectively enrolled 108 aldosterone-producing adenoma patients undergoing adrenalectomy. We conducted repeated measurements of pulse wave velocity at baseline, 6 months, and 12 months after adrenalectomy, grouped by KCNJ5 mutational status. Prognostic factors of arterial stiffness and risk for hypertension at 12 months after adrenalectomy were analyzed after propensity score matching in a 1:1 ratio. After matching for age, sex and body mass index, 88 patients were divided equally into KCNJ5-mutant and non-mutant groups. KCNJ5 mutational status was not an independent variable in either the generalized estimating equation model (p = 0.147) or the percentage change of brachial-ankle pulse wave velocity (p = 0.106). The generalized additive model smoothing plot showed that aldosterone-producing adenoma patients who carried the KCNJ5 mutation and were aged between 37 and 60 may have a hypertension recovery advantage. According to our observations during a 12-month follow-up after adrenalectomy, KCNJ5 mutational status was not associated with improvement in arterial stiffness.