Prospective appraisal of the prevalence of primary aldosteronism in hypertensive patients presenting with atrial flutter or fibrillation (PAPPHY Study): rationale and study design

Atrial fibrillation as presenting sign of primary aldosteronism: results of the Prospective Appraisal on the Prevalence of Primary Aldosteronism in Hypertensive (PAPPHY) Study

BACKGROUND

Despite hyperaldosteronism being suggested as predisposing to arrhythmias, the relationship between atrial fibrillation and primary aldosteronism remains uncertain. Therefore, we tested the hypothesis that atrial fibrillation is a presentation of primary aldosteronism in hypertensive patients with unexplained atrial fibrillation.

DESIGN AND METHODS

The Prospective Appraisal on the Prevalence of Primary Aldosteronism in Hypertensive (PAPPHY) Study recruited consecutive patients with atrial fibrillation and an unambiguous diagnosis of arterial hypertension at three referral centers for hypertension.

RESULTS

In a cohort entailing 411 atrial fibrillation patients, we identified 18% (age 61 ± 11 years; 32% women), who showed no known cause of the arrhythmia. A thorough diagnostic work-up allowed us to identify primary aldosteronism in 73 of these patients, i.e. 42% [95% confidence interval (CI) 31.8-53.9]. Subtyping of primary aldosteronism demonstrated that surgically curable forms of primary aldosteronism accounted for 48% of the cases (95% CI 31.9-65.2). The high prevalence of primary aldosteronism was confirmed at sensitivity analyses.

CONCLUSION

These results provided compelling evidence that primary aldosteronism is highly prevalent in hypertensive patients with unexplained atrial fibrillation. Accordingly, they suggest that patients with no identifiable cause of the arrhythmia should be screened for primary aldosteronism to identify those who can be cured or markedly improved with target treatment. CLINICAL TRIAL REGISTRATION: :: https://clinicaltrials.gov, Identifier: NCT01267747.

Evolution of the Primary Aldosteronism Syndrome: Updating the Approach

CONTEXT

New approaches are needed to address the evolution of the primary aldosteronism syndrome and to increase its recognition. Herein, we review evidence indicating that primary aldosteronism is a prevalent syndrome that is mostly unrecognized, and present a pragmatic and pathophysiology-based approach to improve diagnosis and treatment.

METHODS

Evidence was gathered from published guidelines and studies identified from PubMed by searching for primary aldosteronism, aldosterone, renin, and hypertension. This evidence was supplemented by the authors' personal knowledge, research experience, and clinical encounters in primary aldosteronism.

INTERPRETATION OF EVIDENCE

Renin-independent aldosterone production is a prevalent phenotype that is diagnosed as primary aldosteronism when severe in magnitude, but is largely unrecognized when milder in severity. Renin-independent aldosterone production can be detected in normotensive and hypertensive individuals, and the magnitude of this biochemical phenotype parallels the magnitude of blood pressure elevation, the risk for incident hypertension and cardiovascular disease, and the likelihood and magnitude of blood pressure reduction with mineralocorticoid receptor antagonist therapy. Expansion of the indications to screen for primary aldosteronism, combined with the use of a pathophysiology-based approach that emphasizes inappropriate aldosterone production in the context of renin suppression, will substantially increase the diagnostic and therapeutic yields for primary aldosteronism.

CONCLUSIONS

The landscape of primary aldosteronism has evolved to recognize that it is a prevalent syndrome of renin-independent aldosterone production that contributes to the pathogenesis of hypertension and cardiovascular disease. Expanding screening indications and simplifying the diagnostic approach will enable implementation of targeted treatment for primary aldosteronism.

Management of primary aldosteronism and mineralocorticoid receptor-associated hypertension

Resistant hypertension is associated with a poor prognosis due to organ damage caused by prolonged suboptimal blood pressure control. The concomitant use of mineralocorticoid receptor (MR) antagonists with other antihypertensives has been shown to improve blood pressure control in some patients with resistant hypertension, and such patients are considered to have MR-associated hypertension. MR-associated hypertension is classified into two subtypes: one with a high plasma aldosterone level, which includes primary aldosteronism (PA), and the other with a normal aldosterone level. In patients with unilateral PA, adrenalectomy may be the first-choice procedure, while in patients with bilateral PA, MR antagonists are selected. In addition, in patients with other types of MR-associated hypertension with high aldosterone levels, MR antagonists may be selected as a first-line therapy. In patients with normal aldosterone levels, ARBs or ACE inhibitors are used as a first-line therapy, and MR antagonists may be used as an add-on agent. Since MR antagonist therapy may have efficacy as a first-line or add-on agent in these patients, it is important to recognize this type of hypertension. Further studies are needed to elucidate the pathogenesis and management of MR-associated hypertension in more detail to improve the clinical outcomes of patients with MR-associated hypertension.

Arterial Hypertension, Aldosterone, and Atrial Fibrillation

PURPOSE

Atrial fibrillation is the most common sustained arrhythmia, with a prevalence of 1-2% in the general population and over 15% in people older than 80 years. Due to aging of the population it imposes an increasing burden on the healthcare system because of the need for life-long pharmacological treatment and the associated increased risk of heart failure and hospitalization. Hence, identification of the factors that predispose to atrial fibrillation it is of utmost relevance.

RECENT FINDINGS

Several conditions exist that are characterized by inappropriately high levels of aldosterone, mostly primary aldosteronism and the severe or drug-resistant forms of arterial hypertension. In these forms, aldosterone can cause prominent target organ damage, mostly in the heart, vasculature, and kidney. This review examines the experimental data and clinical evidences that support a link between hyperaldosteronism and atrial fibrillation, and how this knowledge should lead to a change in our management of the hypertensive patients presenting with atrial fibrillation.

11 C-Metomidate PET/CT is a useful adjunct for lateralization of primary aldosteronism in routine clinical practice

OBJECTIVE

To describe clinical practice experience of ¹¹ C-Metomidate PET/CT as an adjunct to adrenal vein sampling (AVS) in the lateralization of aldosterone-producing adenomas (APA) in primary aldosteronism (PA).

CONTEXT

Accurate lateralization of APA in the setting of PA offers the potential for surgical cure and improved long-term cardiovascular outcomes. Challenges associated with AVS, the current gold standard lateralization modality, mean that only a small proportion of potentially eligible patients currently make it through to surgery. This has prompted consideration of alternative strategies for lateralization, including the application of novel molecular PET tracers such as ¹¹ C-Metomidate.

DESIGN

Clinical Service Evaluation/Retrospective audit.

PATIENTS

Fifteen individuals with a confirmed diagnosis of PA, undergoing lateralization with ¹¹ C-Metomidate PET/CT prior to final clinical decision on surgical vs medical management.

MEASUREMENTS

All patients underwent screening aldosterone renin ratio (ARR), followed by confirmatory testing with the seated saline infusion test, according to Endocrine Society Clinical Practice Guidelines. Adrenal glands were imaged using dedicated adrenal CT. ¹¹ C-Metomidate PET/CT was undertaken due to equivocal or failed AVS. Management outcomes were assessed by longitudinal measurement of blood pressure, ARR, number of hypertensive medications following adrenalectomy or institution of medical therapy.

RESULTS

We describe the individual lateralization and clinical outcomes for 15 patients with PA.

CONCLUSION

¹¹ C-Metomidate PET/CT in conjunction with adrenal CT and AVS provided useful information which aided clinical decision-making for PA within a multidisciplinary hypertension clinic.

Effect of unilateral adrenalectomy on the quality of life of patients with lateralized primary aldosteronism

Background

Primary aldosteronism (PA) is associated with an increased prevalence of anxiety and depression. Subnormal quality of life (QoL) scores in PA patients may be improved after surgical treatment. The aim of the study was to assess the impact of surgery on health-related QoL and depression status of patients suffering from PA, comparing the results with a control group of patients undergoing surgery for non-secreting adrenal tumors.

Methods

Data on QoL and depression status were prospectively collected, from January 2014 to January 2017, before, early after surgery (at 1 month) and at late follow up (at least 6 months) in patients with unilateral PA and in a control group with non-secreting adrenal tumors submitted to unilateral laparoscopic adrenalectomy. QoL was assessed using the Short Form 36 (SF-36) Health Survey for Physical (PCS) and Mental Component (MCS); the depression status by a 20-item depression scale (DS) questionnaire.

Results

Twenty-six PA patients and 15 controls were recruited. Biochemical cure of the disease was achieved following surgery in all PA patients; hypertension was cured in 31% of cases and improved in the remaining 69% of cases. No morbidity occurred in both groups. There were no significant differences between PA patients and controls concerning demographics, preoperative PCS, MCS and DS values. In patients with PA, MCS values improved at early (42.72 ± 13.68 vs 51.56 ± 9.03, p = 0.0005) and late follow up (42.72 ± 13.68 vs 51.81 ± 7.04, p < 0.0001); also DS values improved at early (15.92 ± 11.98 vs 8.3 ± 8.8, p = 0.0002) and late follow up (15.92 ± 11.98 vs 4.57 ± 6.11, p < 0.0001). In PA patients PCS values significantly improved at late follow up (51.02 ± 8.04 vs 55.85 ± 5.1, p = 0.013). Also in controls an improvement of MCS and DS scores was found at early and late follow up compared to preoperative values, while no significant differences in PCS were found.

Conclusions

Both PA and non-secreting adrenal tumors affect health-related QoL, worsening MCS and DS scores. Adrenalectomy is effective in curing PA, and improving MCS and DS scores at early and late follow-up, in patients with PA and non-secreting adrenal tumors. In PA patient surgery also significantly improves PCS at late follow up.

Primary aldosteronism in the primary care setting

PURPOSE OF REVIEW

The aim of the present manuscript is to provide an overview of the most updated studies on the prevalence of primary aldosteronism in primary care and to compare these figures with the actual rate of diagnosis in clinical practice and with the prevalence of primary aldosteronism in specific subgroup of patients.

RECENT FINDINGS

Over the last 20 years the clinical spectrum of low renin hypertension and primary aldosteronism has changed dramatically. Once considered only in the presence of severe hypertension and hypokalemia, it is now well known that primary aldosteronism is not uncommon even in patients with mild forms of hypertension and/or normokalemia. Moreover, recent evidence points toward a large proportion of normotensive study participants as being affected by subclinical primary aldosteronism, which represents a strong risk factor for incident hypertension. Moreover, primary aldosteronism patients are exposed to an increased risk of cardio and cerebrovascular events and metabolic comorbidities compared with patients affected by essential hypertension. Disappointingly, primary aldosteronism remains a largely underdiagnosed and undertreated disorder.

SUMMARY

These recent findings further highlight the importance of widening the spectrum of patients who should be screened for primary aldosteronism, to reduce the cardiovascular risk associated with this medical condition.

Primary aldosteronism and thyroid disorders in atrial fibrillation: A Swedish nationwide case–control study

Background

Atrial fibrillation is associated with hyperthyroidism. Patients with primary aldosteronism have an increased prevalence of atrial fibrillation. However, the prevalence of primary aldosteronism in the atrial fibrillation population is unknown.

Aim

This nationwide case–control study aimed to compare the prevalence of primary aldosteronism and thyroid disorders in patients with atrial fibrillation with that of age- and sex-matched controls.

Methods

We identified all atrial fibrillation cases in Sweden between 1987 and 2013 ( n = 713,569) by using the Swedish National Patient Register. A control cohort without atrial fibrillation was randomly selected from the Swedish Total Population Register with a case to control ratio of 1:2. This control cohort was matched for age, sex and place of birth ( n = 1,393,953).

Results

The prevalence of primary aldosteronism in December 2013 was 0.056% in the atrial fibrillation cohort and 0.024% in controls. At the same time, the prevalence of hypothyroidism was 5.9% in the atrial fibrillation cohort and 3.7% in controls. The prevalence of hyperthyroidism was 2.3% in the atrial fibrillation cohort and 0.8% in controls.

Conclusion

This study shows, for the first time, a doubled prevalence of primary aldosteronism in a large cohort of patients with atrial fibrillation compared with the general population. There is also an increased prevalence of hypo- and hyper-thyroidism in patients with atrial fibrillation compared with the general population.

Cardiometabolic outcomes and mortality in medically treated primary aldosteronism: a retrospective cohort study

BACKGROUND

Mineralocorticoid receptor (MR) antagonists are the recommended medical therapy for primary aldosteronism. Whether this recommendation effectively reduces cardiometabolic risk is not well understood. We aimed to investigate the risk of incident cardiovascular events in patients with primary aldosteronism treated with MR antagonists compared with patients with essential hypertension.

METHODS

We did a cohort study using patients from a research registry from Brigham and Women's Hospital, Massachusetts General Hospital, and their affiliated partner hospitals. We identified patients with primary aldosteronism using International Classification of Disease, 9th and 10th Revision codes, who were assessed between the years 1991-2016 and were at least 18 years of age. We excluded patients who underwent surgical adrenalectomy, had a previous cardiovascular event, were not treated with MR antagonists, or had no follow-up visits after study entry. From the same registry, we identified a population with essential hypertension that was frequency matched by decade of age at study entry. We extracted patient cohort data and collated it into a de-identified database. The primary outcome was an incident cardiovascular event, defined as a composite of incident myocardial infarction or coronary revascularisation, hospital admission with congestive heart failure, or stroke, which was assessed using adjusted Cox regression models. Secondary outcomes were the individual components of the composite cardiovascular outcome, as well as incident atrial fibrillation, incident diabetes, and death.

FINDINGS

We identified 602 eligible patients with primary aldosteronism treated with MR antagonists and 41 853 age-matched patients with essential hypertension from the registry. The two groups of patients had comparable cardiovascular risk profiles and blood pressure throughout the study. The incidence of cardiovascular events was higher in patients with primary aldosteronism on MR antagonists than in patients with essential hypertension (56·3 [95% CI 48·8-64·7] vs 26·6 [26·1-27·2] events per 1000 person-years, adjusted hazard ratio 1·91 [95% CI 1·63-2·25]; adjusted 10-year cumulative incidence difference 14·1 [95% CI 10·1-18·0] excess events per 100 people). Patients with primary aldosteronism also had higher adjusted risks for incident mortality (hazard ratio [HR] 1·34 [95% CI 1·06-1·71]), diabetes (1·26 [1·01-1·57]), and atrial fibrillation (1·93 [1·54-2·42]). Compared with essential hypertension, the excess risk for cardiovascular events and mortality was limited to patients with primary aldosteronism whose renin activity remained suppressed (<1 μg/L per h) on MR antagonists (adjusted HR [2·83 [95% CI 2·11-3·80], and 1·79 [1·14-2·80], respectively) whereas patients who were treated with higher MR antagonist doses and had unsuppressed renin (≥1 μg/L per h) had no significant excess risk.

INTERPRETATION

The current practice of MR antagonist therapy in primary aldosteronism is associated with significantly higher risk for incident cardiometabolic events and death, independent of blood pressure control, than for patients with essential hypertension. Titration of MR antagonist therapy to raise renin might mitigate this excess risk.

FUNDING

US National Institutes of Health.

Managing resistant hypertension: focus on mineralocorticoid-receptor antagonists

Mineralocorticoid-receptor antagonists (MRAs) have proven to be effective in some types of hypertension, especially in resistant hypertension (RHTN). In this phenotype of hypertension, the renin-angiotensin-aldosterone pathway plays an important role, with MRAs being especially effective in reducing blood pressure. In this review, we show the relevance of aldosterone in RHTN, as well as some clinical characteristics of this condition and the main concepts involving its pathophysiology and cardiovascular damage. We analyzed the mechanisms of action and clinical effects of two current MRAs - spironolactone and eplerenone - both of which are useful in RHTN, with special attention to the former. RHTN represents a significant minority (10%-15%) of hypertension cases. However, primary-care physicians, cardiologists, nephrologists, neurologists, and geriatricians face this health problem on a daily basis. MRAs are likely one of the best pharmacological options in RHTN patients; however, they are still underused.

Aldosterone and renin in cardiac patients referred for catheterization

Little is known regarding alterations of the renin-angiotensin system in patients referred for cardiac catheterization. Here, we measured plasma levels of active renin and aldosterone in patients referred for cardiac catheterization in order to determine the prevalence of elevated renin, aldosterone, and the aldosterone-renin ratio.A chemiluminescence assay was used to measure plasma aldosterone concentration (PAC) and active renin levels in 833 consecutive patients, after an overnight fasting and without any medication for least 12 hours. We evaluated associations of the hormonal elevations in relation to hypertension, atrial fibrillation (AF), hypertensive cardiomyopathy, coronary artery disease (CAD), valvular disease, impaired left ventricular ejection fraction (LVEF < 35%), and pulmonary hypertension (arterial pulmonary mean pressure >25 mm Hg).Hyperaldosteronism occurred in around one-third of all examined patients, without significant differences between patients with or without the named cardiac diseases. In a comparison between patients with or without any given cardiac disease condition, renin was significantly elevated in patients with either hypertension (36.4% vs 15.9%), CAD (33.9% vs 22.1%), or impaired LVEF (47.3% vs 24.8%). The angiotensin-renin ratio was elevated in AF patients and in patients with hypertensive cardiomyopathy. Patients with AF and coexisting hypertension had elevated renin more frequently than AF patients without coexisting hypertension (35.3% vs 16.5%; P  =  .005). Patients with persistent/permanent AF more frequently had elevated renin than patients with paroxysmal AF (34.1% vs 15.8%; P  =  .007).This prospective study of consecutive cardiac disease patients referred for cardiac catheterization has revealed distinct cardiac disease condition-associated differences in the frequencies of elevations in plasma renin, PAC, and the aldosterone-renin ratio.

Anti-arrhythmic strategies for atrial fibrillation: The role of computational modeling in discovery, development, and optimization

Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with increased risk of cerebrovascular stroke, and with several other pathologies, including heart failure. Current therapies for AF are targeted at reducing risk of stroke (anticoagulation) and tachycardia-induced cardiomyopathy (rate or rhythm control). Rate control, typically achieved by atrioventricular nodal blocking drugs, is often insufficient to alleviate symptoms. Rhythm control approaches include antiarrhythmic drugs, electrical cardioversion, and ablation strategies. Here, we offer several examples of how computational modeling can provide a quantitative framework for integrating multiscale data to: (a) gain insight into multiscale mechanisms of AF; (b) identify and test pharmacological and electrical therapy and interventions; and (c) support clinical decisions. We review how modeling approaches have evolved and contributed to the research pipeline and preclinical development and discuss future directions and challenges in the field.

Primary aldosteronism and pregnancy

Hypertension (HT) is a complication of 8% of all pregnancies and 10% of HT cases are due to primary aldosteronism (PA). There is very little data on PA and pregnancy. Given the changes in the renin angiotensin system during pregnancy, the diagnosis of PA is difficult to establish during gestation. It may be suspected in hypertensive patients with hypokalemia. A comprehensive literature review identified reports covering 40 pregnancies in patients suffering from PA. Analysis of these cases shows them to be high-risk pregnancies leading to maternal and fetal complications. Pregnancy must be programmed, and if the patient has a unilateral form of PA, adrenalectomy should be performed prior to conception. It is customary to stop spironolactone prior to conception and introduce antihypertensive drugs that present no risk of teratogenicity. When conventional antihypertensive drugs used during pregnancy fail to control high blood pressure, diuretics, including potassium-sparing diuretics may be prescribed. Adrenalectomy can be considered during the second trimester of pregnancy exclusively in cases of refractory hypertension. A European retrospective study is currently underway to collect a larger number of cases.

Impact of aldosterone antagonists on the substrate for atrial fibrillation: aldosterone promotes oxidative stress and atrial structural/electrical remodeling

Atrial fibrillation (AF), the most common cardiac arrhythmia, is an electrocardiographic description of a condition with multiple and complex underlying mechanisms. Oxidative stress is an important driver of structural remodeling that creates a substrate for AF. Oxidant radicals may promote increase of atrial oxidative damage, electrical and structural remodeling, and atrial inflammation. AF and other cardiovascular morbidities activate angiotensin (Ang-II)-dependent and independent cascades. A key component of the renin-angiotensin-aldosterone system (RAAS) is the mineralocorticoid aldosterone. Recent studies provide evidence of myocardial aldosterone synthesis. Aldosterone promotes cardiac oxidative stress, inflammation and structural/electrical remodeling via multiple mechanisms. In HF patients, aldosterone production is enhanced. In patients and in experimental HF and AF models, aldosterone receptor antagonists have favorable influences on cardiac remodeling and oxidative stress. Therapeutic approaches that seek to reduce AF burden by modulating the aldosterone system are likely beneficial but underutilized.