QT interval in patients with primary aldosteronism and low-renin essential hypertension

TRPM7 deficiency exacerbates cardiovascular and renal damage induced by aldosterone-salt

Hyperaldosteronism causes cardiovascular disease as well as hypomagnesemia. Mechanisms are ill-defined but dysregulation of TRPM7, a Mg²⁺-permeable channel/α-kinase, may be important. We examined the role of TRPM7 in aldosterone-dependent cardiovascular and renal injury by studying aldosterone-salt treated TRPM7-deficient (TRPM7^+/Δkinase) mice. Plasma/tissue [Mg²⁺] and TRPM7 phosphorylation were reduced in vehicle-treated TRPM7^+/Δkinase mice, effects recapitulated in aldosterone-salt-treated wild-type mice. Aldosterone-salt treatment exaggerated vascular dysfunction and amplified cardiovascular and renal fibrosis, with associated increased blood pressure in TRPM7^+/Δkinase mice. Tissue expression of Mg²⁺-regulated phosphatases (PPM1A, PTEN) was downregulated and phosphorylation of Smad3, ERK1/2, and Stat1 was upregulated in aldosterone-salt TRPM7-deficient mice. Aldosterone-induced phosphorylation of pro-fibrotic signaling was increased in TRPM7^+/Δkinase fibroblasts, effects ameliorated by Mg²⁺ supplementation. TRPM7 deficiency amplifies aldosterone-salt-induced cardiovascular remodeling and damage. We identify TRPM7 downregulation and associated hypomagnesemia as putative molecular mechanisms underlying deleterious cardiovascular and renal effects of hyperaldosteronism.

Deficiency of the Mg2+-permeable channel/α-kinase TRPM7 in mice increases susceptibility to cardiovascular and renal fibrosis induced by aldosterone and salt.

Approach to the Patient with Primary Aldosteronism: Utility and Limitations of Adrenal Vein Sampling

Several studies over the past 3 decades document a higher prevalence of primary aldosteronism (PA) among hypertensive patients than generally presumed. PA exists as a spectrum from mild to severe aldosterone excess. Although a variety of PA subtypes exist, the 2 most common are aldosterone-producing adenomas (APAs) and bilateral hyperaldosteronism (BHA). The distinction is important, because APA-and other subtypes, with aldosterone production mostly from 1 adrenal-can be cured surgically, and BHA should be treated medically with mineralocorticoid-receptor antagonists (MRAs). The major shortcomings in the tailored management of patients with possible PA are the low rates of screening for case identification and the expensive and technically challenging imaging and interventional procedures required to distinguish APA from BHA, especially adrenal vein sampling (AVS). When AVS identifies an APA and allows the patient to be cured surgically, the procedure is of great value. In contrast, the patient with BHA is treated with MRA whether AVS is performed or not. Consequently, it is prudent to gauge how likely it is to benefit from imaging and AVS in each case prior to embarking on these studies. The explosion of information about PA in the past decade, including predictors of APA and of surgical benefit, are useful in limiting the evaluation for some patients with a positive PA screening test. This article will review our suggestions for approaching these patients in a pragmatic style, recognizing the limitations to even the best resources and facilities.

Real-World Effectiveness of Mineralocorticoid Receptor Antagonists in Primary Aldosteronism

OBJECTIVE

To investigate how often target renin is pursued and achieved in patients with primary aldosteronism (PA) and other low renin hypertension (LRH) treated with mineralocorticoid receptor antagonists (MRAs), as reversal of renin suppression was shown to circumvent the enhanced cardiovascular and renal morbidity and mortality in these patients.

PATIENTS AND METHODS

We conducted a retrospective cohort study of patients with PA and LRH treated with MRAs in an academic outpatient practice from January 1, 2000, through May 31, 2020.

RESULTS

Of 30,777 patients with hypertension treated with MRAs, only 7.3% were evaluated for PA. 163 patients (123 with PA) had renin followed after MRA initiation. After a median follow-up of 124 [interquartile range, 65-335] days, 70 patients (43%) no longer had renin suppression at the last visit. The proportion of those who achieved target renin was higher in LRH than in PA (53% vs. 40%). Lower baseline serum potassium, lower MRA doses, and beta-blocker use were independently associated with lower odds of achieving target renin in PA, while male sex was associated with target renin in LRH. Overall, 50 patients (30.7%) had 55 adverse events, all from spironolactone, and 26 patients (52%) were switched to eplerenone or had a spironolactone dose reduction.

CONCLUSION

Despite evidence that reversal of renin suppression confers cardio-renal protection in patients with PA and LRH, renin targets are followed in very few and are achieved in under half of such patients seen in an academic setting, with possibly even lower rates in community practices.

Cardiovascular risk in primary aldosteronism: A systematic review and meta-analysis

AIM

This study aimed to evaluate whether the increased cardiovascular risk and the incidence of cerebrovascular (CCV) events in hypertensive patients were related to primary aldosteronism (PA).

METHODS

The PubMed, EmBase, and the Cochrane Central Register of Controlled Trials were searched to evaluate the risk of CCV in PA patients and compared to essential hypertension (EH) patients. The mean differences (MD) and the risk ratios (RR) were calculated to assess the risk of main outcomes, such as stroke, coronary artery disease, left ventricular hypertrophy (LVH), levels of systolic blood pressure (SBP), diastolic blood pressure (DBP), blood glucose, and urinary potassium.

RESULTS

We identified 31 individual studies including 4546 patients in PA group and 52,284 patients in EH group. Our results revealed that PA was significantly associated with increased risk of stroke (RR=2.03, 95% CI = 1.71-2.39, Pheterogeneity = .331, I = 12.7%), coronary artery disease (RR = 1.67, 95% CI = 1.23-2.25, Pheterogeneity = .043, I = 48.3%), and LVH (RR = 1.54, 95% CI = 1.29-1.83, Pheterogeneity = .004, I = 62.6%) when compared with those in the EH group. Moreover, PA group had significantly increased levels of SBP (WMD = 4.14, 95% CI = 2.60-5.68, Pheterogeneity < .001, I = 84.3%), DBP (WMD = 2.65, 95% CI = 1.83-3.47, Pheterogeneity < .001, I = 77.7%), and urinary potassium (SMD = 0.04, 95% CI = -0.03-0.11, Pheterogeneity = .827, I = 0%) when compared to EH group. However, no significant difference was observed in the levels of blood glucose between the groups.

CONCLUSIONS

These findings suggested that PA significantly increased the risk of cardiac and cerebrovascular complications. In addition, patients with PA might benefit from a periodic assessment of CCV risk.

Cardiovascular events and target organ damage in primary aldosteronism compared with essential hypertension: a systematic review and meta-analysis

BACKGROUND

There is conflicting evidence, relying on heterogeneous studies, as to whether aldosterone excess is responsible for an increased risk of cardiovascular and cerebrovascular complications in patients with primary aldosteronism. We aimed to assess the association between primary aldosteronism and adverse cardiac and cerebrovascular events, target organ damage, diabetes, and metabolic syndrome, compared with the association of essential hypertension and these cardiovascular and end organ events, by integrating results of previous studies.

METHODS

We did a meta-analysis of prospective and retrospective observational studies that compared patients with primary aldosteronism and essential hypertension, to analyse the association between primary aldosteronism and stroke, coronary artery disease (as co-primary endpoints), atrial fibrillation and heart failure, target organ damage, metabolic syndrome, and diabetes (as secondary endpoints). We searched MEDLINE and Cochrane Library for articles published up to Feb 28, 2017, with no start date restriction. Eligible studies compared patients with primary aldosteronism with patients with essential hypertension (as a control group) and reported on the clinical events or endpoints of interest. We also compared primary aldosteronism subtypes, aldosterone-producing adenoma, and bilateral adrenal hyperplasia.

FINDINGS

We identified 31 studies including 3838 patients with primary aldosteronism and 9284 patients with essential hypertension. After a median of 8·8 years (IQR 6·2-10·7) from the diagnosis of hypertension, compared with patients with essential hypertension, patients with primary aldosteronism had an increased risk of stroke (odds ratio [OR] 2·58, 95% CI 1·93-3·45), coronary artery disease (1·77, 1·10-2·83), atrial fibrillation (3·52, 2·06-5·99), and heart failure (2·05, 1·11-3·78). These results were consistent for patients with aldosterone-producing adenoma and bilateral adrenal hyperplasia, with no difference between these subgroups. Similarly, primary aldosteronism increased the risk of diabetes (OR 1·33, 95% CI 1·01-1·74), metabolic syndrome (1·53, 1·22-1·91), and left ventricular hypertrophy (2·29, 1·65-3·17).

INTERPRETATION

Diagnosing primary aldosteronism in the early stages of disease, with early initiation of specific treatment, is important because affected patients display an increased cardiovascular risk compared with patients with essential hypertension.

FUNDING

None.

Cardiovascular complications in patients with primary hyperaldosteronism

Objective.Primary aldosteronism (PA) is a common reason of secondary arterial hypertension (HTN) and is associated with an increased risk of cardiovascular complications, chronic kidney disease and mortality. The aim of this study was to compare the prevalence of cardiovascular complications in patients with PA and HTN and show the peculiarities of cardiovascular system involvement in hyperaldosteronism.Design and methods.We included 191 (77,0  %) females and 57 (23,0  %) males with suspected PA aged from 19 to 86 years old. Other reasons for secondary HTN were excluded. Diagnosis of PA was based on Endocrine Society recommendations (2009).Results.PA diagnosis was confirmed in 41 (16,5  %) subjects. Systolic blood pressure was higherin patients with PA than in patients with essential hypertension, but diastolic blood pressure did not differ. Microalbuminuria was found in 61,0  % of patients with PA and only in 41,6  % of hypertensive subjects (р < 0,05). Study showed that prevalence of stroke, angina pectoris, myocardial infarction as well as arrhythmia were the same in both patients’ group. On the other hand, 29,3  % with PA had chronic heart disease compared to only 12,0  % among patients with essential HTN (p < 0,05).Conclusions.We showed that HTN associated with autonomic aldosterone production leads to more frequent cardiovascular complications. Hence, early PA diagnosis and treatment is an important approach of modern medicine.

Influence of steroid hormones on ventricular repolarization

QT interval prolongation, corrected for heart rate (QTc), either spontaneous or drug-induced, is associated with an increased risk of torsades de pointes and sudden death. Women have longer QTc than men and are at higher risk of torsades de pointes, particularly during post-partum and the follicular phase. Men with peripheral hypogonadism have longer QTc than healthy controls. The role of the main sex steroid hormones has been extensively studied with inconsistent findings. Overall, estradiol is considered to promote QTc lengthening while progesterone and testosterone shorten QTc. New findings suggest more complex regulation of QTc by sex steroid hormones involving gonadotropins (i.e. follicle-stimulating hormone), the relative concentrations of sex steroid hormones (which depends on gender, i.e., progesterone/estradiol ratio in women). Aldosterone, another structurally related steroid hormone, can also prolong ventricular repolarization in both sex. Better understanding of pathophysiological hormonal processes which may lead to increased susceptibility of women (and possibly hypogonadic men) to drug-induced arrhythmia may foster preventive treatments (e.g. progesterone in women). Exogenous hormonal intake might offer new therapeutic opportunities or, alternatively, increase the risk of torsades de pointes. Some exogenous sex steroids may also have paradoxical effects on ventricular repolarization. Lastly, variations of QTc in women linked to the menstrual cycle and sex hormone fluctuations are generally ignored in regulatory thorough QT studies. Investigators and regulatory agencies promoting inclusion of women in thorough QT studies should be aware of this source of variability especially when studying drugs over several days of administration.

Aldosterone-to-Renin Ratio Is Associated With Reduced 24-Hour Heart Rate Variability and QTc Prolongation in Hypertensive Patients

Aldosterone is considered to exert direct effects on the myocardium and the sympathetic nervous system. Both QT time and heart rate (HR) variability (HRV) are considered to be markers of arrhythmic risk and autonomous dysregulation. In this study, we investigated the associations between aldosterone, QT time, and HRV in patients with arterial hypertension.We recruited 477 hypertensive patients (age: 60.2 ± 10.2 years; 52.3% females) with a mean systolic/diastolic 24-hour ambulatory blood pressure monitoring (ABPM) value of 128 ± 12.8/77.1 ± 9.2 mmHg and with a median of 2 (IQR: 1-3) antihypertensive agents. Patients were recruited from the outpatient clinic at the Department of Internal Medicine of the Medical University of Graz, Austria. Blood samples, 24-hour HRV derived from 24-hour blood pressure monitoring (ABPM) and ECG's were obtained. Plasma aldosterone and plasma renin concentrations were measured by means of a radioimmunoassay. Twenty-four-hour urine specimens were collected in parallel with ABPM.Mean QTc was 423.3 ± 42.0 milliseconds for males and 434.7 ± 38.3 milliseconds for females. Mean 24H-HR and 24H-HRV was 71.9 ± 9.8 and 10.0 ± 3.6 bpm, respectively. In linear regression analyses adjusted for age, sex, body mass index, ABPM, and current medication, aldosterone to active renin ratio (AARR) was significantly associated with the QTc interval, a marker for cardiac repolarization abnormalities (mean = 426 ± 42.4 milliseconds; β-coefficient = 0.121; P = 0.03) as well as with the 24-hour heart rate variability a surrogate for autonomic dysfunction (median = 9.67 [IQR = 7.38-12.22 bpm]; β-coefficient = -0.133; P = 0.01).In hypertensive patients, AARR is significantly related to QTc prolongation as well as HRV. Further studies investigating the effects of mineralocorticoid receptor blocker and aldosterone synthase inhibitors on QTc and HRV are warranted.

Issues in the Diagnosis and Treatment of Primary Aldosteronism

Primary aldosteronism (PA) is associated with a high rate of cardio- and cerebrovascular complications and metabolic alterations. PA is also recognized as the most frequent, although often unrecognized, secondary form of hypertension. Guidelines have been released to assist clinicians in the diagnostic work-up and subtype differentiation of PA. In this review we discuss and compare the available guidelines in the context of our professional experience and evaluate diagnostic and therapeutic aspects that are still a matter of debate.

Electrical and Myocardial Remodeling in Primary Aldosteronism

OBJECTIVE AND DESIGN

Primary aldosteronism (PA) represents the most common cause of secondary hypertension. A higher risk of cardiovascular events has been reported in patients with PA than in otherwise similar patients with essential hypertension (EH). So far, only a few studies investigated the electrocardiographic changes in PA patients compared to EH patients.

METHODS

To investigate the electrocardiographic changes and heart remodeling in PA, we enrolled 61 consecutive patients, 30 with PA [12 with aldosterone-producing adrenal cortical adenoma (APA) and 18 with bilateral adrenal hyperplasia-idiopathic adrenal hyperplasia] and 30 with EH. In all subjects, electrocardiographic parameters were evaluated from 12-lead electrocardiograms and heart remodeling with echocardiogram.

RESULTS

No significant differences in age, sex, body mass index, and blood pressure were found in two groups. The P wave and PR interval duration were significantly prolonged in patients with PA respect to EH (p < 0.003 and <0.002, respectively). A first degree atrio-ventricular block was present in 16% of the patients with PA and only in 3.2% of those with EH. In PA patients, the interventricular septum thickness (IVST) correlated with PR duration (r = 0.51; p < 0.03). Left ventricular hypertrophy was present in 53% of the patients with PA and in 26% of the patients with EH (χ(2), p < 0.03).

CONCLUSION

In this case-control study, patients with PA show more anatomic and electrical heart remodeling than those with EH. We hypothesize that in patients with PA these cardiac changes may play a role for the increased risk of future cardiovascular events.

Male pseudohermaphroditism presented with sudden cardiac arrest

Torsades de pointes is a life-threatening arrhythmia associated with a number of causes, but is very rare among endocrinologic disorders. We report a case of male pseudohermaphroditism with hyperaldosteronism due to a 17α-hydroxylase deficiency presented with sudden cardiac arrest.

Diagnosis and treatment of low-renin hypertension

Plasma renin levels can be used to classify hypertension. A significant proportion of hypertensive individuals display a low-renin profile and thus low-renin hypertension (LRH) requires appropriate diagnosis and treatment. LRH includes essential, secondary and genetic forms, the most common of which are low-renin essential hypertension and primary aldosteronism. Several studies have investigated the relationship between PRA status and clinical response to different antihypertensive therapies. The present review will discuss the differential diagnosis of LRH subtypes and the most appropriate treatment options based on the pathophysiological background of this condition.