Mineralocorticoid Receptor Antagonism in Patients With Atrial Fibrillation: Findings From the ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) Registry

The Effect of Mineralocorticoid Receptor 3 Antagonists on Anti-Inflammatory and Anti-Fatty Acid Transport Profile in Patients with Heart Failure

Epicardial fat thickness is associated with cardiovascular disease. Mineralocorticoid receptor antagonist (MRA), a pharmaceutical treatment for CVD, was found to have an effect on adipose tissue. Our aim was to analyse the main epicardial fat genesis and inflammation-involved cell markers and their regulation by risk factors and MRA. We included blood and epicardial or subcutaneous fat (EAT or SAT) from 71 patients undergoing heart surgery and blood from 66 patients with heart failure. Cell types (transcripts or proteins) were analysed by real-time polymerase chain reaction or immunohistochemistry. Plasma proteins were analysed by Luminex technology or enzyme-linked immunoassay. Our results showed an upregulation of fatty acid transporter levels after aldosterone-induced genesis. The MRA intake was the main factor associated with lower levels in epicardial fat. On the contrary, MRA upregulated the levels and its secretion of the anti-inflammatory marker intelectin 1 and reduced the proliferation of epicardial fibroblasts. Our results have shown the local MRA intake effect on fatty acid transporters and anti-inflammatory marker levels and the proliferation rate on epicardial fat fibroblasts. They suggest the role of MRA on epicardial fat genesis and remodelling in patients with cardiovascular disease. Translational perspective: the knowledge of epicardial fat genesis and its modulation by drugs might be useful for improving the treatments of cardiovascular disease.

Achievement and quality measure attainment in patients hospitalized with atrial fibrillation: Results from The Get With The Guidelines - Atrial Fibrillation (GWTG-AFIB) registry

BACKGROUND

The Get With The Guidelines - Atrial Fibrillation (GWTG-AFIB) Registry uses achievement and quality measures to improve the care of patients with atrial fibrillation (AF). We sought to evaluate overall and site-level variation in attainment of these measures among sites participating in the GWTG-AFIB Registry.

METHODS

From the GWTG-AFIB registry, we included patients with AF admitted between 1/3/2013 and 6/30/2019. We described patient-level attainment and variation in attainment across sites of 6 achievement measures with 1) defect-free scores (percent of patients with all eligible measures attained), and 2) composite opportunity scores (percent of all eligible patient measures attained). We also described attainment of 11 quality measures at the patient-level.

RESULTS

Among 80,951 patients hospitalized for AF (age 70±13 years, 47.0% female; CHA2DS2-VASc 3.6±1.8) at 132 sites. Site-level defect-free scores ranged from 4.7% to 85.8% (25th, 50th, 75th percentile: 32.7%, 52.1%, 64.4%). Composite opportunity scores ranged from 39.4% to 97.5% (25th, 50th, 75th: 68.1%, 80.3%, 87.1%). Attainment was notably low for the following quality measures: 1) aldosterone antagonist prescription when ejection fraction ≤35% (29% of those eligible); and 2) avoidance of antiplatelet therapy with OAC in patients without coronary/peripheral artery disease (81% of those eligible).

CONCLUSIONS

Despite high overall attainment of care measures across GWTG-AFIB registry sites, large site variation was present with meaningful opportunities to improve AF care beyond OAC prescription, including but not limited to prescription of aldosterone antagonists in those with AF and systolic dysfunction and avoidance of non-indicated adjunctive antiplatelet therapy.

Posttranslational Modifications of the Mineralocorticoid Receptor and Cardiovascular Aging

During aging, the cardiovascular system is especially prone to a decline in function and to life-expectancy limiting diseases. Cardiovascular aging is associated with increased arterial stiffness and vasoconstriction as well as left ventricular hypertrophy and reduced diastolic function. Pathological changes include endothelial dysfunction, atherosclerosis, fibrosis, hypertrophy, inflammation, and changes in micromilieu with increased production of reactive oxygen and nitrogen species. The renin-angiotensin-aldosterone-system is an important mediator of electrolyte and blood pressure homeostasis and a key contributor to pathological remodeling processes of the cardiovascular system. Its effects are partially conveyed by the mineralocorticoid receptor (MR), a ligand-dependent transcription factor, whose activity increases during aging and cardiovascular diseases without correlating changes of its ligand aldosterone. There is growing evidence that the MR can be enzymatically and non-enzymatically modified and that these modifications contribute to ligand-independent modulation of MR activity. Modifications reported so far include phosphorylation, acetylation, ubiquitination, sumoylation and changes induced by nitrosative and oxidative stress. This review focuses on the different posttranslational modifications of the MR, their impact on MR function and degradation and the possible implications for cardiovascular aging and diseases.

Heart failure patients with atrial fibrillation benefit from remote patient management: insights from the TIM-HF2 trial

Aims

Atrial fibrillation (AF) is a frequent comorbidity in patients with heart failure (HF). HF patients with AF are characterized by high morbidity and increased risk of hospitalizations. We assessed the effects of remote patient management (RPM) in HF patients with AF compared with usual care (UC) in the TIM‐HF2 trial.

Methods and results

For this post‐hoc analysis, AF status at randomization was assessed in 1537 patients with HF. The primary outcome was the percentage of days lost due to unplanned cardiovascular hospital admissions or death of any cause.

Around 966 patients had sinus rhythm (SR) and 571 had AF. The analysis showed a significant interaction between heart rhythm and all‐cause mortality (P for interaction = 0.001). AF patients had more days lost due to unplanned cardiovascular hospitalization than SR patients (7.53%, CI 6.01–9.05 vs. 4.90%, CI 3.98–5.82, ratio 1.54, P = 0.004) and higher all‐cause mortality (11.9%, CI 9.4–14.9 vs. 8.5%, CI 6.8–10.4, HR 0.66, CI 0.47–0.94, P = 0.029). Patients with AF randomized to RPM had significantly less days lost due to unplanned cardiovascular hospital admissions or all‐cause death (5.64%, CI 3.81–7.48) than patients with AF randomized to UC (9.37%, CI 6.98–11.76, ratio 0.60, P = 0.015). No difference was seen in SR patients (UC: 5.25%, CI 3.93–6.58, RPM: 4.55%, CI 3.27–5.83, ratio 0.87, P = 0.452). All‐cause mortality in AF patients was reduced with 9.2% (CI 6.1–13.2) in the RPM group compared with 14.5% (CI 10.7–18.1) in the UC group (HR 0.60, CI 0.36–1.00, P = 0.050).

Conclusions

For patients with atrial fibrillation at study entry, RPM was associated with increased days alive out of hospital. Our results identify HF patients with atrial fibrillation as a promising target population for RPM.

Incidence of Atrial Fibrillation and Mineralocorticoid Receptor Activity in Patients With Medically and Surgically Treated Primary Aldosteronism

Importance

Primary aldosteronism (PA) is an ideal condition to evaluate the role of the mineralocorticoid receptor (MR) in the pathogenesis of atrial fibrillation (AF).

Objective

To investigate whether MR antagonist therapy or surgical adrenalectomy in PA influence the risk for incident AF.

Design

This cohort study included patients aged 18 years and older. Patients with PA and age-matched patients with essential hypertension were identified via electronic health records. Patients with a history of AF, myocardial infarction, congestive heart failure, or stroke were excluded. Data were collected between 1991 and the end of 2016 in an academic medical center, with a mean follow-up duration of approximately 8 years.

Exposures

Patients with PA treated with MR antagonists or surgical adrenalectomy were compared with patients with essential hypertension. Patients with PA who were treated with MR antagonists were categorized by whether their plasma renin activity remained suppressed (< 1 ng/mL/h) or substantially increased (≥ 1 ng/mL/h), as proxies for insufficient or sufficient MR blockade.

Main Outcomes and Measure

Incident AF.

Results

A total of 195 patients with PA who were treated with MR antagonists and 201 patients with PA treated with surgical adrenalectomy were included, as well as 40 092 age-matched patients with essential hypertension. Despite similar blood pressure at study entry and throughout follow-up, patients with PA who were treated with MR antagonists whose renin remained suppressed had a higher risk for incident AF than patients with essential hypertension (adjusted HR, 2.55 [95% CI, 1.75-3.71]). They also had an adjusted 10-year cumulative AF incidence difference of 14.1 (95% CI, 6.7-21.5) excess cases per 100 persons compared with patients with essential hypertension. In contrast, patients with PA who were treated with MR antagonists and whose renin increased and patients with PA who were treated with surgical adrenalectomy had no statistically significant difference in risk for incident AF compared with patients with essential hypertension.

Conclusions and Relevance

When compared with patients with essential hypertension, patients with PA treated with MR antagonists such that renin remained suppressed (as a proxy for insufficient MR blockade) had a significantly higher risk for incident AF; however, treatment of PA with MR antagonists to substantially increase renin (suggesting sufficient MR blockade), or with surgical adrenalectomy (to remove the source of aldosteronism), was associated with no significant difference in risk for developing AF. These findings add to the growing body of evidence suggesting that MR blockade may be a potential therapy to decrease the incidence of AF.

Role of Aldosterone and Mineralocorticoid Receptor in Cardiovascular Aging

The mineralocorticoid receptor (MR) was originally identified as a regulator of blood pressure, able to modulate renal sodium handling in response to its principal ligand aldosterone. MR is expressed in several extra-renal tissues, including the heart, vasculature, and adipose tissue. More recent studies have shown that extra-renal MR plays a relevant role in the control of cardiovascular and metabolic functions and has recently been implicated in the pathophysiology of aging. MR activation promotes vasoconstriction and acts as a potent pro-fibrotic agent in cardiovascular remodeling. Aging is associated with increased arterial stiffness and vascular tone, and modifications of arterial structure and function are responsible for these alterations. MR activation contributes to increase blood pressure with aging by regulating myogenic tone, vasoconstriction, and vascular oxidative stress. Importantly, aging represents an important contributor to the increased prevalence of cardiometabolic syndrome. In the elderly, dysregulation of MR signaling is associated with hypertension, obesity, and diabetes, representing an important cause of increased cardiovascular risk. Clinical use of MR antagonists is limited by the adverse effects induced by MR blockade in the kidney, raising the risk of hyperkalaemia in older patients with reduced renal function. Therefore, there is an unmet need for the enhanced understanding of the role of MR in aging and for development of novel specific MR antagonists in the context of cardiovascular rehabilitation in the elderly, in order to reduce relevant side effects.