Aldosterone Pathway Blockade to Prevent Atrial Fibrillation: A Systematic Review and Meta-Analysis

Effects of mineralocorticoid receptor antagonists on new-onset or recurrent atrial fibrillation: a Bayesian and frequentist network meta-analysis of randomized trials

Background Clinical and translational research suggests that mineralocorticoid receptor antagonists (MRAs) may prevent atrial fibrosis and electrical remodeling associated with atrial fibrillation (AF). This study aimed to consolidate existing evidence from randomized controlled trials (RCTs) evaluating the effect of MRAs on incident or recurrent AF. Methods Medline, Cochrane Library and Scopus were searched until February 12, 2024. Triple-independent study selection, data extraction and quality assessment were performed. Evidence was pooled using both pairwise and Bayesian and frequentist network meta-analyses. Results Twenty-three RCTs (13,358 participants) were identified. Based on the pairwise random effects meta-analysis, MRAs were associated with a significant reduction in AF events compared to placebo or usual care (risk ratio {RR}= 0.75; 95% confidence interval {CI}= [0.66, 0.87]; P< 0.001; I2= 3%). This protective effect was robust both for new-onset and recurrent AF episodes (subgroup p-value= 0.69), while the baseline HF status was not a significant effect modifier (subgroup p-value= 0.58). MRAs demonstrated a significantly higher reduction in AF events for patients with chronic renal disease compared to placebo (RR= 0.78; 95% CI= [0.62, 0.98]; P= 0.03; I2= 0%). The network meta-analyses revealed that only spironolactone was associated with a significant reduction in AF events (Bayesian RR= 0.76; 95% CI= [0.65, 0.89]; P< 0.001; level of evidence moderate; SUCRA 0.731), while eplerenone and finerenone showed a neutral effect. Conclusion MRAs confer a significant benefit in terms of reducing incident or recurrent AF episodes, irrespective of HF status. In this context, spironolactone may be preferable compared to eplerenone or finerenone.

Incidence and progression of atrial fibrillation in patients with and without heart failure using mineralocorticoid receptor antagonists: a meta-analysis

BACKGROUND

Mineralocorticoid receptor antagonists (MRAs) have emerged as potential therapy to target the underlying arrhythmogenic substrate in atrial fibrillation (AF). Nevertheless, there have been inconsistent results on the impact of MRAs on AF.

OBJECTIVE

We sought to evaluate the effect of MRAs on AF incidence and progression in patients with and without heart failure.

METHODS

Electronic databases were searched up to September, 2022 for randomized controlled trials (RCTs) that evaluated MRA use and reported AF outcomes. Primary outcome was a composite of new-onset or recurrent AF. Safety outcomes included hyperkalemia and gynecomastia risks. A random-effects meta-analysis estimated pooled odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

12 RCTs, comprising 11,419 patients treated with various MRAs were included [5960 (52%) on MRA]. On follow-up (6-39 months), 714 (5.5%) patients developed AF. MRA therapy was associated with a 32% reduction in the risk of new-onset or recurrent AF [OR 0.68 (95% CI 0.51-0.92), I2 = 40%]. On subgroup analysis, the greatest benefit magnitude was demonstrated in reducing AF recurrence [OR 0.50 (95% CI 0.30-0.83)] and among patients with left ventricular dysfunction [OR 0.59 (95% CI 0.40-0.85)]. Gynecomastia, but not hyperkalemia, was associated with MRA use. Meta-regression analysis demonstrated that therapy duration was a significant interaction factor driving the effect size (Pinteraction = 0.013).

CONCLUSION

MRA use is associated with a reduction in AF risk, especially AF progression. A prominent effect is seen in patients with heart failure, further augmented by therapy duration. Prospective trials are warranted to evaluate MRA use as upstream therapy for preventing this common arrhythmia.

Mineralocorticoid receptor antagonists and atrial fibrillation: a meta-analysis of clinical trials

BACKGROUND AND AIMS

Mineralocorticoid receptor antagonists (MRAs) improve cardiovascular outcomes in a variety of settings. This study aimed to assess whether cardioprotective effects of MRAs are modified by heart failure (HF) and atrial fibrillation (AF) status and to study their impact on AF events.

METHODS

MEDLINE, Embase, and Cochrane Central databases were searched to 24 March 2023 for randomized controlled trials evaluating the efficacy of MRAs as compared with placebo or usual care in reducing cardiovascular outcomes and AF events in patients with or at risk for cardiovascular diseases. Random-effects models and interaction analyses were used to test for effect modification.

RESULTS

Meta-analysis of seven trials (20 741 participants, mean age: 65.6 years, 32% women) showed that the efficacy of MRAs, as compared with placebo, in reducing a composite of cardiovascular death or HF hospitalization remains consistent across patients with HF [risk ratio = 0.81; 95% confidence interval (CI): 0.67-0.98] and without HF (risk ratio = 0.84; 95% CI: 0.75-0.93; interaction P = .77). Among patients with HF, MRAs reduced cardiovascular death or HF hospitalization in patients with AF (hazard ratio = 0.95; 95% CI: 0.54-1.66) to a similar extent as in those without AF (hazard ratio = 0.82; 95% CI: 0.63-1.07; interaction P = .65). Pooled data from 20 trials (21 791 participants, mean age: 65.2 years, 31.3% women) showed that MRAs reduce AF events (risk ratio = 0.76; 95% CI: 0.67-0.87) in both patients with and without prior AF.

CONCLUSIONS

Mineralocorticoid receptor antagonists are similarly effective in preventing cardiovascular events in patients with and without HF and most likely retain their efficacy regardless of AF status. Mineralocorticoid receptor antagonists may also be moderately effective in preventing incident or recurrent AF events.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Low plasma renin activity is associated with "Apparently" idiopathic atrial fibrillation

Background

Previous studies have reported the direct or indirect relationship between the renin-angiotensin-aldosterone system (RAAS) and atrial fibrillation (AF). However, in patients with "apparently" idiopathic AF without possible external influence, whether RAAS is dysregulated at an early stage of AF and its relationship with the recurrence of AF after ablation have not been studied.

Methods

This single-center, prospective, case-control study included apparently healthy individuals with AF (the case group) or paroxysmal supraventricular tachycardia (PSVT, the control group) referred for catheter ablation at the same period. The primary outcome was RAAS activation in these two groups. The secondary outcome was the 1-year recurrence of AF after ablation.

Results

This study included 51 "apparently" idiopathic AF and 91 patients with PSVT. A greater proportion of patients in the case group had plasma renin activity (PRA) levels < 1 ng/ml/h compared to the control group (25.5 % vs. 7.7 %, P = 0.003). PRA < 1 ng/ml/h was the only factor found to be associated with the diagnose of AF in both the univariate model (odds ratio [OR] 4.11, 95 % confidence interval [CI] 1.52-11.11, P = 0.005) and the model adjusted for age and sex (OR 3.98, 95 % CI 1.20-13.25, P = 0.024). A similar pattern was seen with paroxysmal AF. No significant difference in the components of RAAS was observed between 11 patients with the recurrence of AF and 40 without the recurrence at the 1-year follow-up.

Conclusions

This observational study revealed an association between low renin activity and the diagnosis of "apparently" idiopathic AF, particularly paroxysmal AF.

Lifestyle changes in atrial fibrillation management and intervention

Atrial fibrillation (AF) is one of the most common arrhythmias in adults, and its continued rise in the United States is complicated by the increased incidence and prevalence of several AF risk factors, such as obesity, physical inactivity, hypertension, obstructive sleep apnea, diabetes mellitus, coronary artery disease, and alcohol, tobacco, or caffeine use. Lifestyle and risk factor modification has been proposed as an additional pillar of AF therapy, added to rhythm control, rate control, and anticoagulation, to reduce AF burden and risk. Although emerging evidence largely supports the integration of lifestyle and risk factor management in clinical practice, randomized clinical trials investigating the long-term sustainability and reproducibility of these benefits remain sparse. The purpose of this review is to discuss potentially reversible risk factors on AF, share evidence for the impact on AF by modification of these risk factors, and then provide an overview of the effects of reversing or managing these risk factors on the success of various AF management strategies, such as antithrombotic, rate control, and rhythm control therapies.

Inhibition of miR-195-3p protects against cardiac dysfunction and fibrosis after myocardial infarction

Cardiac fibrosis following myocardial infarction is a major risk factor for heart failure. Recent evidence suggests that miR-195-3p is up-regulated in fibrotic diseases, including kidney and liver fibrosis. However, its function and underlying mechanisms in cardiac fibrosis after MI remain unknown. To investigate the role of miR-195-3p in MI-induced cardiac fibrosis, we established acute MI models by ligating adult C57B/L6 mice LAD coronary artery while sham-operated mice were used as controls. In vivo inhibition of miR-195-3p was conducted by intramyocardial injection of AAV9-anti-miR-195-3p. In vitro overexpression and inhibition of miR-195-3p were performed by transfecting cultured Cardiac Fibroblasts (CFs) with synthetic miRNA mimic and inhibitor. Our results showed that MI induced the expression of miR-195-3p and that inhibition of miR-195-3p reduced myofibroblast differentiation and collagen deposition and protected cardiac function. In vitro stimulation of CFs with TGF-β1 resulted in a significant increase in miR-195-3p expression. Inhibition of miR-195-3p attenuated the TGF-β1-induced expression of ECM proteins, migration, and proliferation. PTEN expression was significantly reduced in the hearts of MI mice, in activated CFs, and in CFs transfected with miR-195-3p mimic. Inhibition of miR-195-3p markedly restored PTEN expression in MI mice and TGF-β1-treated CFs. In conclusion, this study highlights the crucial role of miR-195-3p in promoting cardiac fibrosis and dysfunction after MI. Inhibiting miR-195-3p could be a promising therapeutic strategy for preventing cardiac fibrosis and preserving cardiac function after MI. Additionally, the study sheds light on the mechanisms underlying the effects of miR-195-3p on fibrosis, including its regulation of PTEN/AKT pathway.

A Systematic Review and Meta-Analysis on Effectiveness of Mineralocorticoid Receptor Antagonists in Reducing the Risk of Atrial Fibrillation

Mineralocorticoid receptor antagonists (MRAs) are known to improve clinical outcomes in heart failure, particularly heart failure with reduced ejection fraction. However, the effect of MRAs on the incidence of and recurrence of atrial fibrillation (AF) is not well established. Therefore, databases, such as PubMed, EMBASE, and Cochrane Central, were searched from inception to September 2021 for randomized controlled trials of MRAs with AF as an outcome. Risk ratios (RRs) with 95% confidence interval (CIs) were combined using the random-effects model. A total of 10 randomized controlled trials (n = 11,356) were included. Our pooled analysis demonstrates that MRAs reduce the risk of AF occurrence by 23% compared with the control therapy (RR 0.77, 95% CI 0.65 to 0.91, p = 0.003, I2 = 40%). Subgroup analysis demonstrated that MRAs reduced the risk of both new-onset AF (RR 0.84, 95% CI 0.61 to 1.16, p = 0.28, I2 = 43%) and recurrent AF (RR 0.73, 95% CI 0.59 to 0.90, p = 0.004, I2 = 26%) similarly; p interaction = 0.48. Our meta-analysis concludes that MRAs reduce the risk of development of AF overall, with consistent effects in new-onset and recurrent AF.

Atrial Cardiomyopathy in Valvular Heart Disease: From Molecular Biology to Clinical Perspectives

This review discusses the evolving topic of atrial cardiomyopathy concerning valvular heart disease. The pathogenesis of atrial cardiomyopathy involves multiple factors, such as valvular disease leading to atrial structural and functional remodeling due to pressure and volume overload. Atrial enlargement and dysfunction can trigger atrial tachyarrhythmia. The complex interaction between valvular disease and atrial cardiomyopathy creates a vicious cycle of aggravating atrial enlargement, dysfunction, and valvular disease severity. Furthermore, atrial remodeling and arrhythmia can predispose to atrial thrombus formation and stroke. The underlying pathomechanism of atrial myopathy involves molecular, cellular, and subcellular alterations resulting in chronic inflammation, atrial fibrosis, and electrophysiological changes. Atrial dysfunction has emerged as an essential determinant of outcomes in valvular disease and heart failure. Despite its predictive value, the detection of atrial fibrosis and dysfunction is challenging and is not included in the clinical routine. Transthoracic echocardiography and cardiac magnetic resonance imaging are the main diagnostic tools for atrial cardiomyopathy. Recently published data have revealed that both left atrial volumes and functional parameters are independent predictors of cardiovascular events in valvular disease. The integration of atrial function assessment in clinical practice might help in early cardiovascular risk estimation, promoting early therapeutic intervention in valvular disease.

Atrial fibrillation: primary prevention, secondary prevention, and prevention of thromboembolic complications: part 1

Atrial fibrillation (AF), is the most common sustained cardiac arrhythmia. It was once thought to be benign as long as the ventricular rate was controlled, however, AF is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a MEDLINE search to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched via the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare noninvasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

Effects of Spironolactone on Arrhythmias in Hemodialysis Patients: Secondary Results of the SPin-D Randomized Controlled Trial

Key Points

The effects of spironolactone on arrhythmia in patients receiving maintenance hemodialysis are unclear. In these post hoc analyses, spironolactone resulted in a higher frequency of bradycardia and conduction blocks, compared with placebo. Close monitoring may be warranted for patients on maintenance hemodialysis receiving MRAs, while definitive trial results are awaited.

Background

Patients receiving maintenance hemodialysis (HD) have a high incidence of cardiovascular events, including arrhythmia and sudden death. Spironolactone reduces the risk of cardiovascular events and sudden death in patients with heart failure, but the effects of spironolactone on arrhythmic events in patients treated with maintenance HD are unclear.

Methods

The Safety and Cardiovascular Efficacy of Spironolactone in Dialysis-Dependent ESRD (SPin-D) trial was a 36-week randomized, placebo-controlled, double-blind trial comparing three different doses of spironolactone with placebo in maintenance HD patients. We performed a post hoc analysis in a subset (n =57) who underwent extended electrocardiographic monitoring using a wearable device at baseline and follow-up. Generalized estimating equations models were fit to determine the associations of spironolactone (individual doses and combined) versus placebo on the incidence rate of predefined categories of arrhythmic events.

Results

The average age of participants was 55±12 years, 61% were male, and 77% were Black. The overall proportion of patients with at least one arrhythmia event was 43% (15/35) at baseline and 81% (43/53) at the end of follow-up. At the end of follow-up, the rate of bradycardic events or conduction blocks was higher in the combined spironolactone group, compared with placebo (82.4 versus 38.7 events/100 patient-days; P <0.001). Similar findings were noted in adjusted models, but did not meet statistical significance (adjusted rate ratio of 2.04; 95% confidence interval 0.83–5.05).

Conclusions

In a 36-week trial of patients receiving maintenance HD, a higher frequency of bradycardia and conduction blocks was observed among those treated with spironolactone treatment compared with placebo. Larger studies are required to investigate the longer-term effects of spironolactone on cardiac conduction in patients receiving HD.

Aldosterone and cardiovascular diseases

Aldosterone's role in the kidney and its pathophysiologic actions in hypertension are well known. However, its role or that of its receptor [minieralocorticoid receptor (MR)] in other cardiovascular (CV) disease are less well described. To identify their potential roles in six CV conditions (heart failure, myocardial infarction, atrial fibrillation, stroke, atherosclerosis, and thrombosis), we assessed these associations in the following four areas: (i) mechanistic studies in rodents and humans; (ii) pre-clinical studies of MR antagonists; (iii) clinical trials of MR antagonists; and (iv) genetics. The data were acquired from an online search of the National Library of Medicine using the PubMed search engine from January 2011 through June 2021. There were 3702 publications identified with 200 publications meeting our inclusion and exclusion criteria. Data strongly supported an association between heart failure and dysregulated aldosterone/MR. This association is not surprising given aldosterone/MR's prominent role in regulating sodium/volume homeostasis. Atrial fibrillation and myocardial infarction are also associated with dysregulated aldosterone/MR, but less strongly. For the most part, the data were insufficient to determine whether there was a relationship between atherosclerosis, stroke, or thrombosis and aldosterone/MR dysregulation. This review clearly documented an expanding role for aldosterone/MR's dysregulation in CV diseases beyond hypertension. How expansive it might be is limited by the currently available data. It is anticipated that with an increased focus on aldosterone/MR's potential roles in these diseases, additional clinical and pre-clinical data will clarify these relationships, thereby, opening approaches to use modulators of aldosterone/MR's action to more precisely treat these CV conditions.

Genetic Predisposition to a Higher Whole Body Water Mass May Increase the Risk of Atrial Fibrillation: A Mendelian Randomization Study

BACKGROUND

Observational studies have found an association between increased whole body water mass (BWM) and atrial fibrillation (AF). However, the causality has yet to be confirmed. To provide feasible protective measures on disease development, we performed Mendelian randomization (MR) design to estimate the potential causal relationship between increased BWM and AF.

METHODS

We implemented a two-sample MR study to assess whether increased BWM causally influences AF incidence. For exposure, 61 well-powered genetic instruments extracted from UK Biobank (N = 331,315) were used as the proxies of BWM. Summary genetic data of AF were obtained from FinnGen (Ncase = 22,068; Ncontrol = 116,926). Inverse-variance weighted (IVW), MR-Egger and weighted median methods were selected to infer causality, complemented with a series of sensitivity analyses. MR-Pleiotropy Residual Sum and Outlier (MR-PRESSO) and Radial MR were employed to identify outliers. Furthermore, risk factor analyses were performed to investigate the potential mechanisms between increased BWM and AF.

RESULTS

Genetic predisposition to increased BWM was demonstrated to be significantly associated with AF in the IVW model (OR = 2.23; 95% CI = 1.47-3.09; p = 1.60 × 10^-7), and the result was consistent in other MR approaches. There was no heterogeneity or pleiotropy detected in sensitivity analysis. MR-PRESSO identified no outliers with potential pleiotropy after excluding outliers by Radial MR. Furthermore, our risk factor analyses supported a positive causal effect of genetic predicted increased BWM on edematous diseases.

CONCLUSIONS

MR estimates showed that a higher BWM could increase the risk of AF. Pathological edema is an important intermediate link mediating this causal relationship.

Levocarnitine regulates the growth of angiotensin II-induced myocardial fibrosis cells via TIMP-1

This study aimed to explore the effects of tissue inhibitor of metalloproteinases-1 (TIMP-1) on levocarnitine (LC)-mediated regulation of angiotensin II (AngII)-induced myocardial fibrosis (MF) and its underlying mechanisms. H9C2 cells were treated with AngII for 24 h to induce fibrosis. The cells were then treated with LC or transfected with TIMP-1-OE plasmid/si‑TIMP-1. Cell apoptosis, viability, migration, and related gene expression were analyzed. AngII treatment significantly upregulated Axl, α-SMA, and MMP3 expression (P < 0.05) and downregulated STAT4 and TIMP1 expression (P < 0.05) relative to the control levels. After transfection, cells with TIMP-1 overexpression/knockdown were successfully established. Compared with that of the control, AngII significantly inhibited cell viability and cell migration while promoting cell apoptosis (P < 0.05). LC and TIMP-1-OE transfection further suppressed cell viability and migration induced by Ang II and upregulated apoptosis, whereas si-TIMP-1 had the opposite effect. Furthermore, LC and TIMP-1-OE transfection downregulated Axl, AT1R, α-SMA, collagen III, Bcl-2, and MMP3 expression caused by AngII and upregulated caspase 3, p53, and STAT4 expression, whereas si-TIMP-1 had the opposite effect. TIMP-1 is therefore a potential therapeutic target for delaying MF progression.

Aggravated Gut Microbiota and Metabolomic Imbalances Are Associated with Hypertension Patients Comorbid with Atrial Fibrillation

Disordered gut microbiota (GM) as the co-contributor of atrial fibrillation (AF) and hypertension (HTN) might be associated with AF risk in HTN. This study aimed to explore the altered GM community and metabolic patterns between 27 HTN patients with AF (HTN-AF) and 27 non-AF HTN patients through fecal metagenomic and serum metabolomic analysis. Compared to non-AF HTN patients, significant microbial alterations (p = 0.004), including increased microbial diversity (p < 0.05), shifted enterotype dominated by Prevotella to Bacteroides, and abundant disease-linked genera Ruminococcus, Streptococcus, Veillonella, Dorea, and Enterococcus, were observed in HTN-AF patients. A species-based random forest prediction model was associated with the risk of AF occurrence in HTN patients. Furthermore, GM metabolic profiles dramatically differed between HTN and HTN-AF patients, especially the imbalance of saturated and unsaturated fatty acids. In HTN-AF patients, circulating palmitic acid and arachidonic acid levels were significantly elevated, while the levels of tetracosahexaenoic acid, oleic acid, linoleic acid, and stearic acid were decreased (p < 0.001, VIP > 1), mediating 85.99% of gut microbial indirect effects on AF (p < 0.001). Thus, our findings preliminarily indicated that exacerbated dysbiosis of GM and relevant metabolites was associated with high AF susceptibility and might be a potential target for AF prediction and prevention in HTN.

Aldosterone as a Mediator of Cardiovascular Damage

Besides the physiological regulation of water, sodium, and potassium homeostasis, aldosterone modulates several physiological and pathological processes in the cardiovascular system. At the vascular level, aldosterone excess stimulates endothelial dysfunction and infiltration of inflammatory cells, enhances the development of the atherosclerotic plaque, and favors plaque instability, arterial stiffness, and calcification. At the cardiac level, aldosterone increases cardiac inflammation, fibrosis, and myocardial hypertrophy. As a clinical consequence, high aldosterone levels are associated with enhanced risk of cardiovascular events and mortality, especially when aldosterone secretion is inappropriate for renin levels and sodium intake, as in primary aldosteronism. Several clinical trials showed that mineralocorticoid receptor antagonists reduce cardiovascular mortality in patients with heart failure and reduced ejection fraction, but inconclusive results were reported for other cardiovascular conditions, such as heart failure with preserved ejection fraction, myocardial infarction, and atrial fibrillation. In patients with primary aldosteronism, adrenalectomy or treatment with mineralocorticoid receptor antagonists significantly mitigate adverse aldosterone effects, reducing the risk of cardiovascular events, mortality, and incident atrial fibrillation. In this review, we will summarize the major preclinical and clinical studies investigating the cardiovascular damage mediated by aldosterone and the protective effect of mineralocorticoid receptor antagonists for the reduction of cardiovascular risk in patients with cardiovascular diseases and primary aldosteronism.

Elevated Lipoprotein(a) and Risk of Atrial Fibrillation: An Observational and Mendelian Randomization Study

BACKGROUND

Atrial fibrillation (AF) is a cardiac arrhythmia associated with an elevated risk of stroke, heart failure, and mortality. However, preventative therapies are needed with ancillary benefits on its cardiovascular comorbidities. Lipoprotein(a) (Lp[a]) is a recognized risk factor for atherosclerotic cardiovascular disease (ASCVD), which itself increases AF risk, but it remains unknown whether Lp(a) is a causal mediator of AF independent of ASCVD.

OBJECTIVES

This study investigated the role of Lp(a) in AF and whether it is independent of ASCVD.

METHODS

Measured and genetically predicted Lp(a) levels were tested for association with 20,432 cases of incident AF in the UK Biobank (N = 435,579). Mendelian randomization analyses were performed by using summary-level data for AF from publicly available genome-wide association studies (N = 1,145,375).

RESULTS

In the UK Biobank, each 50 nmol/L (23 mg/dL) increase in Lp(a) was associated with an increased risk of incident AF using measured Lp(a) (HR: 1.03; 95% CI: 1.02-1.04 ; P = 1.65 × 10^-8) and genetically predicted Lp(a) (OR: 1.03; 95% CI: 1.02-1.05; P = 1.33 × 10^-5). Mendelian randomization analyses using independent data replicated the effect (OR: 1.04 per 50 nmol/L Lp[a] increase; 95% CI: 1.03-1.05 per 50 nmol/L Lp[a] increase; P = 9.23 × 10^-10). There was no evidence of risk-conferring effect from low-density lipoprotein cholesterol or triglycerides, and only 39% (95% CI: 27%-73%) of Lp(a) risk was mediated through ASCVD, suggesting that Lp(a) partly influences AF independent of its known effects on ASCVD.

CONCLUSIONS

Our findings implicate Lp(a) as a potential causal mediator in the development of AF which show that the effects of Lp(a) extend across myocardial tissues. Ongoing clinical trials for Lp(a)-lowering therapies should evaluate effects on AF prevention.

Prognostic Impact and Predictors of New-Onset Atrial Fibrillation in Heart Failure

Background: The prognostic impact and predictors of NOAF in HF patients are not fully elucidated. This study aims to determine whether new-onset atrial fibrillation (NOAF) affects patient outcome and investigate predictors of atrial fibrillation (AF) in acute heart failure (HF) patients using real-world data. Methods: The factors associated with NOAF in 2894 patients with sinus rhythm (SR) enrolled in the Korean Acute Heart Failure (KorAHF) registry were investigated. Survival was analyzed using AF as a time-dependent covariate. Relevant predictors of NOAF were analyzed using multivariate proportional hazards models. Results: Over 27.4 months, 187 patients developed AF. The median overall survival time was over 48 and 9.9 months for the SR and NOAF groups, respectively. Cox regression analysis with NOAF as a time-dependent covariate showed a higher risk of death among patients with NOAF. Multivariate Cox modeling showed that age, worsening HF, valvular heart disease (VHD), loop diuretics, lower heart rate, larger left atrium (LA) diameter, and elevated creatinine levels were independently associated with NOAF. Risk score indicated the number of independent predictors. The incidence of NOAF was 2.9%, 9.4%, and 21.8% in the low-risk, moderate-risk, and high-risk groups, respectively (p < 0.001). Conditional inference tree analysis identified worsening HF, heart rate, age, LA diameter, and VHD as discriminators. Conclusions: NOAF was associated with decreased survival in acute HF patients with SR. Age, worsening HF, VHD, loop diuretics, lower heart rate, larger LA diameter, and elevated creatinine could independently predict NOAF. This may be useful to risk-stratify HF patients at risk for AF.

The role of inflammation in the pathogenesis and treatment of arrhythmias

The pathogenesis of arrhythmias is complex and multifactorial. The role of inflammation in the pathogenesis of both atrial and ventricular arrhythmias (VA) has been explored. However, developing successful pharmacotherapy regimens based on those pathways has proven more of a challenge. This narrative review provides an overview of five common arrhythmias impacted by inflammation, including atrial fibrillation (AF), myocardial infarction, arrhythmogenic cardiomyopathy, cardiac sarcoidosis, and QT prolongation, and the potential role for anti-inflammatory therapy in their management. We identified arrhythmias and arrhythmogenic disease states with the most evidence linking pathogenesis to inflammation and conducted comprehensive searches of United States National Library of Medicine MEDLINE^® and PubMed databases. Although a variety of agents have been studied for the management of AF, primarily in an effort to reduce postoperative AF following cardiac surgery, no standard anti-inflammatory agents are used in clinical practice at this time. Although inflammation following myocardial infarction may contribute to the development of VA, there is no clear benefit with the use of anti-inflammatory agents at this time. Similarly, although inflammation is clearly linked to the development of arrhythmias in arrhythmogenic cardiomyopathy, data demonstrating a benefit with anti-inflammatory agents are limited. Cardiac sarcoidosis, an infiltrative disease eliciting an immune response, is primarily treated by immunosuppressive therapy and steroids, despite a lack of primary literature to support such regimens. In this case, anti-inflammatory agents are frequently used in clinical practice. The pathophysiology of arrhythmias is complex, and inflammation likely plays a role in both onset and duration, however, for most arrhythmias the role of pharmacotherapy targeting inflammation remains unclear.

Atrial Fibrillation and Aortic Ectasia as Complications of Primary Aldosteronism: Focus on Pathophysiological Aspects

Primary aldosteronism (PA) is the most common cause of secondary hypertension. A growing body of evidence has suggested that, beyond its well-known effects on blood pressure and electrolyte balance, aldosterone excess can exert pro-inflammatory, pro-oxidant and pro-fibrotic effects on the kidney, blood vessels and heart, leading to potentially harmful pathophysiological consequences. In clinical studies, PA has been associated with an increased risk of cardiovascular, cerebrovascular, renal and metabolic complication compared to essential hypertension, including atrial fibrillation (AF) and aortic ectasia. An increased prevalence of AF in patients with PA has been demonstrated in several clinical studies. Aldosterone excess seems to be involved in the pathogenesis of AF by inducing cardiac structural and electrical remodeling that in turn predisposes to arrhythmogenicity. The association between PA and aortic ectasia is less established, but several studies have demonstrated an effect of aldosterone on aortic stiffness, vascular smooth muscle cells and media composition that, in turn, might lead to an increased risk of aortic dilation and dissection. In this review, we focus on the current evidence regarding the potential role of aldosterone excess in the pathogenesis of AF and aortic ectasia.

Roles of Mineralocorticoid Receptors in Cardiovascular and Cardiorenal Diseases

Mineralocorticoid receptor (MR) activation in the heart and vessels leads to pathological effects, such as excessive extracellular matrix accumulation, oxidative stress, and sustained inflammation. In these organs, the MR is expressed in cardiomyocytes, fibroblasts, endothelial cells, smooth muscle cells, and inflammatory cells. We review the accumulating experimental and clinical evidence that pharmacological MR antagonism has a positive impact on a battery of cardiac and vascular pathological states, including heart failure, myocardial infarction, arrhythmic diseases, atherosclerosis, vascular stiffness, and cardiac and vascular injury linked to metabolic comorbidities and chronic kidney disease. Moreover, we present perspectives on optimization of the use of MR antagonists in patients more likely to respond to such therapy and review the evidence suggesting that novel nonsteroidal MR antagonists offer an improved safety profile while retaining their cardiovascular protective effects. Finally, we highlight future therapeutic applications of MR antagonists in cardiovascular injury.

Prevention and Treatment of Atrial Fibrillation via Risk Factor Modification

Atrial fibrillation (AF) is the most common clinically significant arrhythmia, and it increases stroke risk. A preventive approach to AF is needed because virtually all treatments such as cardioversion, antiarrhythmic drugs, ablation, and anticoagulation are associated with high cost and carry significant risk. A systematic review was performed to identify effective lifestyle-based strategies for reducing primary and secondary AF. A PubMed search was performed using articles up to March 1, 2021. Search terms included atrial fibrillation, atrial flutter, exercise, diet, metabolic syndrome, type 2 diabetes mellitus, obesity, hypertension, stress, tobacco smoking, alcohol, Mediterranean diet, sodium, and omega-3 fatty acids. Additional articles were identified from the bibliographies of retrieved articles. The control of hypertension, ideally with a renin-angiotensin-aldosterone system inhibitor, is effective for preventing primary AF and recurrence. Obstructive sleep apnea is a common cause of AF, and treating it effectively reduces AF episodes. Alcohol increases the risk of AF in a dose-dependent manner, and abstinence reduces risk of recurrence. Sedentary behavior and chronic high-intensity endurance exercise are both risk factors for AF; however, moderate physical activity is associated with lower risk of AF. Recently, sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 agonists have been associated with reduced risk of AF. Among overweight/obese patients, weight loss of ≥10% is associated with reduced AF risk. Lifestyle changes and risk factor modification are highly effective for preventing AF.

Abnormal Calcium Handling in Atrial Fibrillation Is Linked to Changes in Cyclic AMP Dependent Signaling

Both, the decreased L-type Ca²⁺ current (I_Ca,L) density and increased spontaneous Ca²⁺ release from the sarcoplasmic reticulum (SR), have been associated with atrial fibrillation (AF). In this study, we tested the hypothesis that remodeling of 3′,5′-cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) signaling is linked to these compartment-specific changes (up- or down-regulation) in Ca²⁺-handling. Perforated patch-clamp experiments were performed in atrial myocytes from 53 patients with AF and 104 patients in sinus rhythm (Ctl). A significantly higher frequency of transient inward currents (I_TI) activated by spontaneous Ca²⁺ release was confirmed in myocytes from AF patients. Next, inhibition of PKA by H-89 promoted a stronger effect on the I_TI frequency in these myocytes compared to myocytes from Ctl patients (7.6-fold vs. 2.5-fold reduction), while the β-agonist isoproterenol (ISO) caused a greater increase in Ctl patients (5.5-fold vs. 2.1-fold). I_Ca,L density was larger in myocytes from Ctl patients at baseline (p < 0.05). However, the effect of ISO on I_Ca,L density was only slightly stronger in AF than in Ctl myocytes (3.6-fold vs. 2.7-fold). Interestingly, a significant reduction of I_Ca,L and Ca²⁺ sparks was observed upon Ca²⁺/Calmodulin-dependent protein kinase II inhibition by KN-93, but this inhibition had no effect on I_TI. Fluorescence resonance energy transfer (FRET) experiments showed that although AF promoted cytosolic desensitization to β-adrenergic stimulation, ISO increased cAMP to similar levels in both groups of patients in the L-type Ca²⁺ channel and ryanodine receptor compartments. Basal cAMP signaling also showed compartment-specific regulation by phosphodiesterases in atrial myocytes from 44 Ctl and 43 AF patients. Our results suggest that AF is associated with opposite changes in compartmentalized PKA/cAMP-dependent regulation of I_Ca,L (down-regulation) and I_TI (up-regulation).

The Dose-Dependent Effects of Spironolactone on TGF-β1 Expression and the Vulnerability to Atrial Fibrillation in Spontaneously Hypertensive Rats

OBJECTIVE

This study tends to assess the dose-dependent effects of spironolactone on TGF-β1 expression, atrial fibrosis, and the vulnerability to atrial fibrillation in spontaneously hypertensive rats (SHRs) and tries to clarify the association of atrial fibrosis with the vulnerability to atrial fibrillation.

METHODS

Forty 20-week-old male SHRs were randomly divided into 4 groups (10 rats per group): 3 spironolactone groups were lower-dose group (10 mg·kg-1·d-1, dissolved in 2 ml saline solution, group SL), medium-dose group (40 mg·kg-1·d-1, dissolved in 2 ml saline solution, group SM), higher-dose group (80 mg·kg-1·d-1, dissolved in 2 ml saline solution, group SH) and one hypertension group (2 ml saline solution for stomach gavage, group H). Ten matched homologous WKY rats were set as the control group (group C). After 7 weeks of gavage, a multiple electroconductive physiological recorder was used to detect atrial electrical parameters, including P-wave duration, PR interval, and atrial effective refractory period (AERP), the inducibility, and duration of atrial fibrillation. HE staining was used to determine myocardial cell size. Masson staining was used to detect the deposition of the interstitial collagen fibers in atrial muscle. The expression of TGF-β1 was detected by immunohistochemistry and western blot.

RESULTS

Compared with group C, the myocardial cell size, atrial fibrosis, TGF-β1 expression, P-wave duration, PR interval, AERP, inducibility, and duration of atrial fibrillation in group H were conspicuously increased (p < 0.05); compared with group H, there was no significant difference in the myocardial cell size, atrial fibrosis, TGF-β1 expression, and electrophysiological indexes in group SH upon spironolactone intervention (p > 0.05); compared with group H, the myocardial cell size, atrial fibrosis, the expression of TGF-β1, P-wave duration, PR interval, the inducibility, and duration of atrial fibrillation in the group SL and group SM were all decreased (p < 0.05); compared with group SM, the effect in the group SL was more prominent (p < 0.01).

CONCLUSION

Hypertension can lead to cardiomyocyte hypertrophy, deposition of interstitial fibrosis in myocardial tissue, and an increase in the vulnerability to atrial fibrillation. Spironolactone showed a certain dose-dependent effect in SHRs. Lower-dose spironolactone was superior to higher-dose spironolactone in the aspect of reducing hypertensive atrial fibrosis and TGF-β1 expression, as well as preventing the occurrence of atrial fibrillation.

Atrial Fibrillation Recurrence Prevention after Electrical Cardioversion in High-Risk Patients – Benefits of Non-Antiarrhythmic Drugs

Background:

Recurrence prevention after Atrial Fibrillation (AF) termination by Eelectrical Cardioversion (ECV) remains challenging. Increasing attention is paid to pathophysiological effects of non-Antiarrhythmic Drugs (non-AADs), nevertheless, with heterogeneous results.

Objective:

We evaluated the potential benefits of different non-AADs as adjunctive therapy to Antiarrhythmic Drugs (AADs) for AF recurrence prevention after sinus rhythm restoration by ECV in high-risk patients.

Methods:

The study was conducted among high-risk AF patients after successful ECV. Prescription of class IC or class III AAD was required. Data were acquired in a face-to-face baseline interview and 1-, 3-, 6-, 9-, 12-month follow-up interviews.

Results:

113 patients were included. Total AF recurrence rate reached 48.7%. Angiotensin-Converting Enzyme Inhibitor (ACEI) or angiotensin receptor blocker (ARB) intake, compared with non-use, demonstrated AF recurrence rate reduction by 8.5% (46.3 vs. 54.8%), with odds ratio (OR) reduced by 28.9% (OR 0.711, 95% confidence interval (CI) 0.310-1.631, p = 0.420). Among mineralocorticoid receptor antagonist (MRA) users, AF recurrence rate was reduced by 25.1% (29.6 vs. 54.7%) and OR by 65.1% (OR 0.349, 95%CI 0.138-0.884, p = 0.023). Present statin therapy reduced AF recurrence rate by 4.2% (46.8 vs. 51.0%) and OR by 15.5% (OR 0.845, 95%CI 0.402-1.774, p = 0.656). Diuretic use showed reduction of AF recurrence rate by 10.2% (41.7 vs. 51.9%) and OR by 33.9% (OR 0.661, 95%CI 0.297-1.469, p = 0.308).

Conclusion:

Non-AADs demonstrated practical benefits as adjunctive therapy to AADs for AF recurrence prevention after ECV in high-risk patients, with statistically significant results established for concomitant MRA intake.

Prospective clinical trial evaluating spironolactone in Doberman pinschers with congestive heart failure due to dilated cardiomyopathy

INTRODUCTION/OBJECTIVES

Whether the aldosterone antagonist spironolactone has beneficial survival effects in dogs with dilated cardiomyopathy (DCM) is not known. The primary objective of the study was to evaluate the effect of spironolactone, when added to conventional therapy, on survival time in Doberman pinschers with congestive heart failure (CHF) due to DCM.

ANIMALS

Sixty-seven client-owned Doberman pinschers with CHF due to DCM.

MATERIALS AND METHODS

The trial design was prospective, randomized, blinded, and placebo controlled. Dogs were randomized to receive 50-75 mg of spironolactone twice daily (n = 34) or a placebo (n = 33), in addition to standard CHF therapy. Follow-up visits were targeted every 1-6 weeks until endpoint. Quality-of-life questionnaire and physical examination were performed at every visit, while renal biochemistry, ECG, echocardiography, and thoracic radiography were reassessed as needed. The primary endpoint was time to cardiac death, defined as death or euthanasia from CHF or sudden death.

RESULTS

Median time to primary endpoint in the spironolactone group (183 days) was not statistically significantly different than that for the placebo group (124 days) (p = 0.254). The development of atrial fibrillation (AF) was significantly less frequent in the spironolactone group (n = 7) than the placebo group (n = 15, p = 0.037).

CONCLUSIONS

While median time to cardiac death in the spironolactone group was not statistically significantly different than that in the placebo group, adding spironolactone to conventional therapy resulted in reduced occurrence of AF.

Radiofrequency catheter ablation combined with spironolactone in the treatment of atrial fibrillation: A single-center randomized controlled study

At present, the question of whether radiofrequency ablation (RFA) combined with spironolactone can reduce the levels of plasma angiotensin II (AngII) and aldosterone (ALD) in patients with atrial fibrillation (AF) and reduce the recurrence of AF has not been reported.

Prognostic association of medication trajectories with 3-year mortality in heart failure and preserved ejection fraction: findings from the EPICAL2 cohort study

PURPOSE

The aims of this study were to describe combinations of beta-blockers (BB), renin-angiotensin system (RAS) blockers, and mineralocorticoid receptor antagonist (MRA) prescriptions and their trajectories in heart failure with preserved ejection fraction (HFpEF) patients, and to assess their effect on the three-year all-cause and cardiovascular (CV)-mortality.

METHODS

We used data from the EPICAL2 cohort of 689 hospitalized HFpEF patients. Medication prescriptions were collected at hospital discharge and at 6, 12, and 24 months after discharge. A multi-trajectory approach was used to conjointly model groups of individuals following similar trajectories over medications prescriptions. We used Cox and Fine-Gray models, to evaluate respectively the associations between 3-year all-cause mortality and CV-mortality and the trajectory groups.

RESULTS

Multi-trajectory modelling revealed five distinct trajectory groups: group1 (N = 232, 33.6%) stable ACEI/ARB and BB prescriptions, group 2 (N = 199, 28.8%) stable ACEI/ARB prescription, group 3 (N = 133, 19.3%) stable BB prescriptions, group 4 (N = 78, 11.3%) stable prescriptions of none of the medications, and group 5 (N = 47, 6.8%) stable ACEI/ARB, BB, and MRA prescriptions. As compared to the group 4 of patients receiving none of the three medications, patients receiving a stable prescription of one or a combination of two or the three medications over 2 years) had a lower overall mortality over 3-year follow-up, i.e., group 1 (HR = 0.5, 95% CI 0.4-0.8), group 2 (HR = 0.6, 95% CI:0.4-0.8), group 3 (HR = 0.5, 95% CI:0.4-0.7), and group 5 (HR = 0.5, 95% CI:0.3-0.9). However, none of these trajectory groups was associated with a lower CV-mortality over 3 years.

CONCLUSION

In an unselected population-based sample of HFpEF patients, the long-term stable use of the combination ACEI/ARB and BB, BB exclusively, ACEI/ARB exclusively, or the combination ACEI/ARB and BB and MRAs was associated with reduced three-year all-cause mortality.

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.

Molecular Basis of Atrial Fibrillation Initiation and Maintenance

Atrial fibrillation (AF) is the most common cardiac arrhythmia, largely associated to morbidity and mortality. Over the past decades, research in appearance and progression of this arrhythmia have turned into significant advances in its management. However, the incidence of AF continues to increase with the aging of the population and many important fundamental and translational underlaying mechanisms remain elusive. Here, we review recent advances in molecular and cellular basis for AF initiation, maintenance and progression. We first provide an overview of the basic molecular and electrophysiological mechanisms that lead and characterize AF. Next, we discuss the upstream regulatory factors conducting the underlying mechanisms which drive electrical and structural AF-associated remodeling, including genetic factors (risk variants associated to AF as transcriptional regulators and genetic changes associated to AF), neurohormonal regulation (i.e., cAMP) and oxidative stress imbalance (cGMP and mitochondrial dysfunction). Finally, we discuss the potential therapeutic implications of those findings, the knowledge gaps and consider future approaches to improve clinical management.

Atrial fibrosis underlying atrial fibrillation (Review)

Atrial fibrillation (AF) is one of the most common tachyarrhythmias observed in the clinic and is characterized by structural and electrical remodelling. Atrial fibrosis, an emblem of atrial structural remodelling, is a complex multifactorial and patient-specific process involved in the occurrence and maintenance of AF. Whilst there is already considerable knowledge regarding the association between AF and fibrosis, this process is extremely complex, involving intricate neurohumoral and cellular and molecular interactions, and it is not limited to the atrium. Current technological advances have made the non-invasive evaluation of fibrosis in the atria and ventricles possible, facilitating the selection of patient-specific ablation strategies and upstream treatment regimens. An improved understanding of the mechanisms and roles of fibrosis in the context of AF is of great clinical significance for the development of treatment strategies targeting the fibrous region. In the present review, a focus was placed on the atrial fibrosis underlying AF, outlining its role in the occurrence and perpetuation of AF, by reviewing recent evaluations and potential treatment strategies targeting areas of fibrosis, with the aim of providing a novel perspective on the management and prevention of AF.

The effects of ACEI/ARB, aldosterone receptor antagonists and statins on preventing recurrence of atrial fibrillation: A protocol for systematic review and network meta-analysis

BACKGROUND

Atrial fibrillation (AF) is one of the most common arrhythmias, and is high relative to cardiovascular morbidity and mortality. AF-related complications and treatment costs bring about huge health burden, therefore the prevention recurrence of AF is imperative. "Upstream therapy" refers to the use of non-antiarrhythmic drugs (non-AADs) that modify the atrial substrate or target-specific mechanisms of AF to prevent the occurrence or recurrence of the arrhythmia. RAAS Blockers, aldosterone receptor antagonists and statins have an effect on preventing recurrence of atrial fibrillation. This protocol is designed for systematic review and network meta-analysis, which will assess comparative effects and safety of various non-antiarrhythmic drugs in preventing recurrence of atrial fibrillation.

METHODS

The Cochrane Library, MEDLINE, EMBASE, ClinicalTrials.gov will be searched from inception to Aug 31, 2020 to identify relevant studies. The Cochrane "Risk of bias" tool will be used to assess the methodological quality of eligible studies. The pair-wise meta-analysis will be performed by STATA 14.0 software. The network meta-analysis will be implemented in a Bayesian framework using Win BUGS 1.4.3 and the package "gemtc" V.0.8.1 of R-3.6.2 software. The network plots will be drawn using STATA 14.0 software. A comparison-adjusted funnel plot will be used to assess the publication bias using STATA 14.0 software. Quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

The results of this network meta-analysis will determine the preventive effect and rank ordering of these interventions for recurrence of AF. The report will follow the PRISMA checklist for network meta-analysis.

CONCLUSION

This network meta-analysis will provide comprehensive evidence-based information in clinical practice.

INPLASY REGISTRATION NUMBER

INPLASY202090004.

New-Onset Atrial Fibrillation in Patients With Primary Aldosteronism Receiving Different Treatment Strategies: Systematic Review and Pooled Analysis of Three Studies

BACKGROUND

Primary aldosteronism (PA) is a common cause of secondary hypertension and associated with higher incidence of new-onset atrial fibrillation (NOAF). However, the effects of surgical or medical therapies on preventing NOAF in PA patents remain unclear. The aim of this meta-analysis study was to assess the risk of NOAF among PA patients receiving mineralocorticoid receptor antagonist (MRA) treatment, PA patients receiving adrenalectomy, and patients with essential hypertension.

METHODS

We performed the meta-analysis of the randomized or observational studies that investigated the incidence rate of NOAF in PA patients receiving MRA treatment versus PA patients receiving adrenalectomy from database inception until December 01, 2020 which were identified from PubMed, Embase, and Cochrane Library.

RESULTS

A total of 172 related studies were reviewed, of which three fulfilled the inclusion criteria, including a total of 2,705 PA patients. The results of meta-analysis demonstrated a higher incidence of NOAF among the PA patients receiving MRA treatment compared to the PA patients receiving adrenalectomy (pooled odds ratio [OR]: 2.83, 95% confidence interval [CI]: 1.76-4.57 in the random effects model, I² = 0%). The pooled OR for the PA patients receiving MRA treatment compared to the patients with essential hypertension was 1.91 (95% CI: 1.11-3.28). The pooled OR for the PA patients receiving adrenalectomy compared to the patients with essential hypertension was 0.70 (95% CI: 0.28-1.79).

CONCLUSION

Compared to the essential hypertension patients and the PA patients receiving adrenalectomy, the patients with PA receiving MRA treatment had a higher risk of NOAF.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42021222022.

Pharmacological agents to therapeutic treatment of cardiac injury caused by Covid-19

SARS-CoV-2 is responsible for the 2019 coronavirus disease (COVID-19), a global pandemic that began in March 2020 and is currently in progress. To date, COVID-19 has caused about 935,000 deaths in more than 200 countries. The respiratory system is most affected by injuries caused by COVID-19, but other organs may be involved, including the cardiovascular system. SARS-CoV-2 penetrates host cells through the angiotensin 2 conversion enzyme (ACE-2). ACE-2 is expressed not only in the lungs, but also in other organs, including the cardiovascular system. Several studies have found that a good percentage of patients with severe COVID-19 have cardiac lesions, including myocardial fibrosis, edema and pericarditis. Pathological remodeling of the extracellular matrix caused by viral infection leads to myocardial fibrotic lesions. These fibrotic scars can cause cardiac dysfunction, reducing the ejection fraction caused by the presence of stiffened myocardial matrix, or cardiac arrhythmias that cause an alteration in the electrical conduction system of the heart. These cardiac dysfunctions can cause death. It is therefore essential to identify cardiac involvement early in order to act with appropriate therapeutic treatments. In this review, we describe what is known about cardiac injury from COVID-19, highlighting effective pharmacological therapeutic solutions to combat cardiac injury, particularly cardiac fibrosis, caused by COVID-19.

Therapeutic options for patients with advanced atrial fibrillation: from lifestyle and medication to catheter and surgical ablation

Atrial fibrillation (AF) is part of a vicious cycle that includes multiple cardiovascular risk factors and comorbidity which can promote atrial remodelling and AF progression. Most AF-related risk factors—hypertension, diabetes, sleep apnoea, obesity and sedentary lifestyle—are in essence modifiable which may prevent AF development. Treatment of associated cardiovascular conditions may prevent both symptoms and future cardiovascular events. For advanced forms of symptomatic AF refractory to lifestyle management and optimal medication, invasive ablation therapies have become a cornerstone. Although electrical trigger isolation from the pulmonary veins is reasonably effective and safe, more potent energy sources including high output-short duration radiofrequency, ultra-low cryo-energy, and electroporation, as well as more sophisticated arrays, balloons, and lattice-tipped catheter tools, are on their way to eliminate existing pitfalls and simplify the procedure. Electroanatomical navigation and mapping systems are becoming available to provide real-time information on ablation lesion quality and the critical pathways of AF in the individual patient to guide more extensive ablation strategies that may enhance long-term outcome for freedom of advanced AF. Surgical techniques, either stand-alone or concomitant to structural cardiac repair, hybrid, or convergent, with novel less invasive access options are developing and can be helpful in situations unsuitable for catheter ablation.

The ABCs of atrial fibrillation

This article provides an outline of the diagnosis and pathogenesis of atrial fibrillation. It introduces a mnemonic for atrial fibrillation treatment guidelines based on recent evidence. Mnemonics use has been associated with improved learning and task organization. Articles using mnemonics to inform clinical practice have been well-received and implemented.

Clinical efficacy of potassium canreonate-canrenone in sinus rhythm restoration among patients with atrial fibrillation - a protocol of a pilot, randomized, double -blind, placebo-controlled study (CANREN-AF trial)

Background

Atrial fibrillation (AF) is the most frequent cardiac arrhythmia which increases the risk of thromboembolic complications and impairs quality of life. An important part of a therapeutic approach for AF is sinus rhythm restoration. Antiarrhythmic agents used in pharmacological cardioversion have limited efficacy and potential risk of proarrhythmia. Simultaneously, underlying conditions of AF should be treated (e.g. electrolyte imbalance, increased blood pressure, neurohormonal disturbances, atrial volume overload). There is still the need for an effective and safe approach to increase AF cardioversion efficacy. This randomized, double-blind, placebo-controlled, superiority clinical study is performed in patients with AF in order to evaluate the clinical efficacy of intravenous canrenone in sinus rhythm restoration.

Methods

Eighty eligible patients with an episode of AF lasting less than 48 h are randomized in a 1:1 ratio to receive canrenone or placebo. Patients randomized to a treatment intervention are receiving canrenone intravenously at a dose of 200 mg within 2–3 min. Subjects assigned to a control group obtain the same volume of 0.9% saline within the same time. The primary endpoint includes return of sinus rhythm documented in the electrocardiogram within 2 h after drug or placebo administration. Other endpoints and safety outcomes analyses, due to expected lack of statistical power, are exploratory.

Discussion

Current evidence supports renin–angiotensin–aldosterone system (RAAS) inhibition as an upstream therapy in AF management. Excess aldosterone secretion results in proarrhythmic effects. Among the RAAS inhibitors, only canrenone is administered intravenously. Canrenone additionally increases the plasma level of potassium, lowers blood pressure and reduces preload. It has been already used in primary and secondary hyperaldosteronism in the course of chronic liver dysfunction and in heart failure.

Trial registration

ClinicalTrials.gov, NCT03536806. Registered on 25 May 2018.

Lifestyle and Risk Factor Modification for Reduction of Atrial Fibrillation: A Scientific Statement From the American Heart Association

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is associated with substantial morbidity, mortality, and healthcare use. Great strides have been made in stroke prevention and rhythm control strategies, yet reducing the incidence of AF has been slowed by the increasing incidence and prevalence of AF risk factors, including obesity, physical inactivity, sleep apnea, diabetes mellitus, hypertension, and other modifiable lifestyle-related factors. Fortunately, many of these AF drivers are potentially reversible, and emerging evidence supports that addressing these modifiable risks may be effective for primary and secondary AF prevention. A structured, protocol-driven multidisciplinary approach to integrate lifestyle and risk factor management as an integral part of AF management may help in the prevention and treatment of AF. However, this aspect of AF management is currently underrecognized, underused, and understudied. The purpose of this American Heart Association scientific statement is to review the association of modifiable risk factors with AF and the effects of risk factor intervention. Implementation strategies, care pathways, and educational links for achieving impactful weight reduction, increased physical activity, and risk factor modification are included. Implications for clinical practice, gaps in knowledge, and future directions for the research community are highlighted.

Plasma aldosterone and atrial mitochondrial functions of patients undergoing cardiac surgery

Aim: Mitochondrial dysfunction (MD) has been associated with poor outcomes after coronary artery bypass graft surgery. Methods: 58 consecutive patients from the ALDO-POAF Study (NCT02814903) were prospectively included. Plasma aldosterone was assessed at the time of the preoperative consultation and mitochondrial functional studies were performed using atrial appendage tissue collected during surgery. Results: Patients with the highest preoperative plasma aldosterone level had a lower mitochondrial respiratory chain functioning and a lower calcium retention capacity. Chronic kidney disease, patient's age and preoperative high-aldosterone were independent predictors of MD in multivariate analysis. Conclusion: These exploratory data support the use of preventive strategies targeting aldosterone and/or mineralocorticoid receptor activation, in order to prevent perioperative MD and associated poor outcomes.

The 2020 Italian Society of Arterial Hypertension (SIIA) practical guidelines for the management of primary aldosteronism

Background and aim

Considering the amount of novel knowledge generated in the last five years, a team of experienced hypertensionlogists was assembled to furnish updated clinical practice guidelines for the management of primary aldosteronism.

Methods

To identify the most relevant studies, the authors utilized a systematic literature review in international databases by applying the PICO strategy, and then they were required to make use of only those meeting predefined quality criteria. For studies of diagnostic tests, only those that fulfilled the Standards for Reporting of Diagnostic Accuracy recommendations were considered.

Results

Each section was jointly prepared by at least two co-authors, who provided Class of Recommendation and Level of Evidence following the American Heart Association methodology. The guidelines were sponsored by the Italian Society of Arterial Hypertension and underwent two rounds of revision, eventually reexamined by an External Committee. They were presented and thoroughly discussed in two face-to-face meetings with all co-authors and then presented on occasion of the 36th Italian Society of Arterial Hypertension meeting in order to gather further feedbacks by all members. The text amended according to these feedbacks was subjected to a further peer review.

Conclusions

After this process, substantial updated information was generated, which could simplify the diagnosis of primary aldosteronism and assist practicing physicians in optimizing treatment and follow-up of patients with one of the most common curable causes of arterial hypertension.

Pharmacological management of atrial fibrillation in patients with heart failure with reduced ejection fraction: review of current knowledge and future directions

Introduction: Both heart failure with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) independently cause significant morbidity and mortality. The two conditions commonly coexist and AF in the setting of HFrEF is associated with worse mortality, hospitalizations, and quality of life compared to HFrEF without AF. Despite the large burden of these conditions, there is no clear optimal management strategy for when they occur together.Areas covered: This review focuses on the pharmacological management of AF in HFrEF. Studies were identified through PubMed search of relevant keywords. The authors review key clinical trials that have influenced management strategies and guidelines. The authors focus on the classes of drugs used to treat AF for both rate and rhythm control strategies including beta-blockers, digoxin, amiodarone, and dofetilide. Additionally, the authors discuss select non-antiarrhythmic medications that affect AF in HFrEF. The authors highlight the strengths and weakness of the data supporting the use of these medications and suggest future directions.Expert opinion: The pharmacological treatment of AF in HFrEF will need further refinement alongside the emerging role of catheter ablation. Novel HF medications and antiarrhythmics offer new tools to prevent the development of AF, as well as for rate and rhythm control strategies.

Effect of Spironolactone on Atrial Fibrillation in Patients with Heart Failure with Preserved Ejection Fraction: Post-Hoc Analysis of the Randomized, Placebo-Controlled TOPCAT Trial

Background

Mineralocorticoid receptor antagonists (MRAs) reduce the risk of atrial fibrillation (AF) in patients with heart failure (HF) and a reduced ejection fraction. The efficacy of MRAs for AF prevention in patients with HF and a preserved ejection fraction (HFpEF) is unclear.

Objectives

We performed a secondary analysis of a randomized placebo-controlled trial to determine the efficacy of spironolactone in reducing new-onset AF and recurrence of AF in 2733 patients with symptomatic HFpEF.

Methods

Patients with and without prevalent AF at baseline were included, and those with permanent AF were excluded. Patients were randomized 1:1 to spironolactone or placebo. The risk of new-onset AF or the recurrence of AF was quantified using hazard ratios (HRs) with corresponding 95% confidence intervals (CIs).

Results

At baseline, 2228 (64.7%) patients had no history of AF (spironolactone, n = 1111; placebo, n = 1117), whereas 505 (18.4%) patients had prevalent AF (spironolactone, n = 260; placebo, n = 245). During a median follow-up of 3.1 years (interquartile range [IQR] 2.0–4.9), the incidence of new-onset AF was similar in both treatment arms: spironolactone 5.2% (n = 58) versus placebo 4.4% (n = 49); p = 0.41. The risk of new-onset AF was similar in both treatment arms: HR 1.19; 95% CI 0.81–1.74; p = 0.38. AF recurrence was also similar in both treatment arms during a median follow-up of 3.3 years (IQR 1.9–4.7): spironolactone 11.5% (n = 30) versus placebo 11.8% (n = 29); p = 1.00. The risk of recurrence of AF did not differ per treatment arm: HR 0.94; 95% CI 0.57–1.58; p = 0.83.

Conclusion

Spironolactone does not reduce the risk of new-onset AF or AF recurrence in patients with HFpEF. This is in contrast to results in cohorts of patients with HF and a reduced ejection fraction.

Clinical trial registration

ClinicalTrials.gov identifier no. NCT00094302 (TOPCAT).

Electronic supplementary material

The online version of this article (10.1007/s40256-019-00353-5) contains supplementary material, which is available to authorized users.

Pharmacological Inhibition of Serine Proteases to Reduce Cardiac Inflammation and Fibrosis in Atrial Fibrillation

Systemic inflammation correlates with an increased risk of atrial fibrillation (AF) and thrombogenesis. Systemic inflammation alters vessel permeability, allowing inflammatory and immune cell migration toward target organs, including the heart. Among inflammatory cells infiltrating the atria, macrophages and mast cell have recently attracted the interest of basic researchers due to the pathogenic mechanisms triggered by their activation. This chemotactic invasion is likely implicated in short- and long-term changes in cardiac cell-to-cell communication and in triggering fibrous tissue accumulation in the atrial myocardium and electrophysiological re-arrangements of atrial cardiomyocytes, thus favoring the onset and progression of AF. Serine proteases are a large and heterogeneous class of proteases involved in several processes that are important for cardiac function and are involved in cardiac diseases, such as (i) coagulation, (ii) fibrinolysis, (iii) extracellular matrix degradation, (iv) activation of receptors (i.e., protease-activated receptors [PPARs]), and (v) modulation of the activity of endogenous signals. The recognition of serine proteases substrates and their involvement in inflammatory/profibrotic mechanisms allowed the identification of novel cardio-protective mechanisms for commonly used drugs that inhibit serine proteases. The aim of this review is to summarize knowledge on the role of inflammation and fibrosis as determinants of AF. Moreover, we will recapitulate current findings on the role of serine proteases in the pathogenesis of AF and the possible beneficial effects of drugs inhibiting serine proteases in reducing the risk of AF through decrease of cardiac inflammation and fibrosis. These drugs include thrombin and factor Xa inhibitors (used as oral anticoagulants), dipeptidyl-peptidase 4 (DPP4) inhibitors, used for type-2 diabetes, as well as novel experimental inhibitors of mast cell chymases.