Effect of Continuous Positive Airway Pressure on Arrhythmia in Atrial Fibrillation and Sleep Apnea: A Randomized Controlled Trial

When the Clock Strikes A-fib

Within the broad spectrum of atrial fibrillation (AF) symptomatology, there is a striking subset of patients with predominant or even solitary nocturnal onset of the arrhythmia. This review covers AF with nocturnal onset, with the aim of defining this distinctive subgroup among patients with AF. A periodicity analysis is provided showing a clear increased onset between 10:00 pm and 7:00 am. Multiple interacting mechanisms are discussed, such as circadian modulation of electrophysiological properties, vagal tone, and sleep disorders, as well as the potential interaction and synergism between these factors, to provide a better understanding of this clinical entity. Lastly, potential therapeutic targets for AF with nocturnal onset are addressed such as upstream therapy for underlying comorbidities, type of drug and timing of drug administration and pulmonary vein isolation, ablation of the ganglionated plexus, and autonomic nervous system modulation. Understanding the underlying AF mechanisms in the individual patient with nocturnal onset will contribute to patient-specific therapy.

Life's Essential 8, Genetic Susceptibility, and Incident Cardiac Arrhythmias: A Population-Based Prospective Cohort Study

BACKGROUND

Ideal cardiovascular health (CVH) has been associated with reduced cardiovascular disease risk and mortality, but its association with cardiac arrhythmias was still unsettled. In this prospective cohort study, we investigated the relationship between CVH and subsequent arrhythmias risk, including atrial fibrillation (AF)/flutter, ventricular arrhythmias, and bradyarrhythmias.

METHODS

Data from 287,264 participants initially free of arrhythmias in the UK Biobank were included in the analysis. Cox regression models were used to examine the relationship between CVH levels calculated by the American Heart Association's Life's Essential 8 (LE8) metrics, with cardiac arrhythmias risk.

RESULTS

During a median follow-up period of 12.8 years, 16,802 incident AF, 2186 incident ventricular arrhythmias, and 4128 incident bradyarrhythmias were identified. After adjustment for confounding factors, participants with high initial CVH levels had significantly lower risks for AF (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.59-0.68), ventricular arrhythmias (HR, 0.48; 95% CI, 0.40-0.59), and bradyarrhythmias (HR, 0.64; 95% CI, 0.55-0.74) compared with those with low CVH levels. Furthermore, each standard deviation (SD) increase in LE8 scores was associated with a 15% lower risk of AF, 21% for ventricular arrhythmias, and 13% for bradyarrhythmias, respectively. In addition, a significant interaction was observed between CVH levels and the genetic risk of AF (P for interaction, 0.021). The reverse correlation seemed to be more noticeable in individuals with a lower genetic susceptibility to AF.

CONCLUSIONS

We concluded that higher levels of CVH, estimated by the LE8 metrics, were associated with significantly reduced risks of AF, ventricular arrhythmias, and bradyarrhythmias.

The Role of Sleep in Cardiovascular Disease

PURPOSE OF REVIEW

Sleep is an important component of cardiovascular (CV) health. This review summarizes the complex relationship between sleep and CV disease (CVD). Additionally, we describe the data supporting the treatment of sleep disturbances in preventing and treating CVD.

RECENT FINDINGS

Recent guidelines recommend screening for obstructive sleep apnea in patients with atrial fibrillation. New data continues to demonstrate the importance of sleep quality and duration for CV health. There is a complex bidirectional relationship between sleep health and CVD. Sleep disturbances have systemic effects that contribute to the development of CVD, including hypertension, coronary artery disease, heart failure, and arrhythmias. Additionally, CVD contributes to the development of sleep disturbances. However, more data are needed to support the role of screening for and treatment of sleep disorders for the prevention of CVD.

Chronic obstructive pulmonary disease and obstructive sleep apnea overlap: who to treat and how?

INTRODUCTION

The co-existence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA), or the overlap syndrome, is common and associated with a distinct pattern of nocturnal hypoxemia and worse clinical outcomes than either disease alone. Consequently, identifying who and how to treat these patients is essential.

AREAS COVERED

Treatment is recommended in all patients with OSA and symptoms or systemic hypertension, but determining symptoms attributable to OSA can be challenging in patients with COPD. Treatment should be considered in asymptomatic patients with moderate to severe OSA and COPD with pulmonary hypertension and comorbid cardiovascular and cerebrovascular disease, especially if marked hypoxic burden. CPAP is effective, but in patients with the overlap syndrome and daytime hypercapnia, high-intensity noninvasive ventilation aiming to lower PaCO2 may have additional benefits. Additionally, in those with severe resting daytime hypoxemia, supplemental oxygen improves survival and should be added to positive airway pressure. The role of alternative non-positive airway pressure therapies in the overlap syndrome needs further study.

EXPERT OPINION

Both COPD and OSA are heterogeneous disorders with a wide range of disease severity and further research is needed to better characterize and prognosticate patients with the overlap syndrome to personalize treatment.

CaMKIIδ-dependent dysregulation of atrial Na+ homeostasis promotes pro-arrhythmic activity in an obstructive sleep apnea mouse model

Background

Obstructive sleep apnea (OSA) has been linked to various pathologies, including arrhythmias such as atrial fibrillation. Specific treatment options for OSA are mainly limited to symptomatic approaches. We previously showed that increased production of reactive oxygen species (ROS) stimulates late sodium current through the voltage-dependent Na+ channels via Ca2+/calmodulin-dependent protein kinase IIδ (CaMKIIδ), thereby increasing the propensity for arrhythmias. However, the impact on atrial intracellular Na+ homeostasis has never been demonstrated. Moreover, the patients often exhibit a broad range of comorbidities, making it difficult to ascertain the effects of OSA alone.

Objective

We analyzed the effects of OSA on ROS production, cytosolic Na+ level, and rate of spontaneous arrhythmia in atrial cardiomyocytes isolated from an OSA mouse model free from comorbidities.

Methods

OSA was induced in C57BL/6 wild-type and CaMKIIδ-knockout mice by polytetrafluorethylene (PTFE) injection into the tongue. After 8 weeks, their atrial cardiomyocytes were analyzed for cytosolic and mitochondrial ROS production via laser-scanning confocal microscopy. Quantifications of the cytosolic Na+ concentration and arrhythmia were performed by epifluorescence microscopy.

Results

PTFE treatment resulted in increased cytosolic and mitochondrial ROS production. Importantly, the cytosolic Na+ concentration was dramatically increased at various stimulation frequencies in the PTFE-treated mice, while the CaMKIIδ-knockout mice were protected. Accordingly, the rate of spontaneous Ca2+ release events increased in the wild-type PTFE mice while being impeded in the CaMKIIδ-knockout mice.

Conclusion

Atrial Na+ concentration and propensity for spontaneous Ca2+ release events were higher in an OSA mouse model in a CaMKIIδ-dependent manner, which could have therapeutic implications.

Sleep apnea and ischemic stroke- a perspective for translational preclinical modelling

Obstructive sleep apnea (OSA) is associated with ischemic stroke. There is, however, a lack of knowledge on the exact cause-effect relationship, and preclinical models of OSA for experimental ischemic stroke investigations are not well characterized. In this review, we discuss sleep apnea and its relationship with stroke risk factors. We consider how OSA may lead to ischemic stroke and how OSA-induced metabolic syndrome and hypothalamic-pituitary axis (HPA) dysfunction could serve as therapeutic targets to prevent ischemic stroke. Further, we examine the translational potential of established preclinical models of OSA. We conclude that metabolic syndrome and HPA dysfunction, which are often overlooked in the context of experimental stroke and OSA studies, are crucial for experimental consideration to improve the body of knowledge as well as the translational potential of investigative efforts.

Association Between Sleep Apnea Treatment and Health Care Resource Use in Patients With Atrial Fibrillation

BACKGROUND

Obstructive sleep apnea (OSA) contributes to the generation, recurrence, and perpetuation of atrial fibrillation, and it is associated with worse outcomes. Little is known about the economic impact of OSA therapy in atrial fibrillation. This retrospective cohort study assessed the impact of positive airway pressure (PAP) therapy adherence on health care resource use and costs in patients with OSA and atrial fibrillation.

METHODS AND RESULTS

Insurance claims data for ≥1 year before sleep testing and 2 years after device setup were linked with objective PAP therapy use data. PAP adherence was defined from an extension of the US Medicare 90-day definition. Inverse probability of treatment weighting was used to create covariate-balanced PAP adherence groups to mitigate confounding. Of 5867 patients (32% women; mean age, 62.7 years), 41% were adherent, 38% were intermediate, and 21% were nonadherent. Mean±SD number of all-cause emergency department visits (0.61±1.21 versus 0.77±1.55 [P=0.023] versus 0.95±1.90 [P<0.001]), all-cause hospitalizations (0.19±0.69 versus 0.24±0.72 [P=0.002] versus 0.34±1.16 [P<0.001]), and cardiac-related hospitalizations (0.06±0.26 versus 0.09±0.41 [P=0.023] versus 0.10±0.44 [P=0.004]) were significantly lower in adherent versus intermediate and nonadherent patients, as were all-cause inpatient costs ($2200±$8054 versus $3274±$12 065 [P=0.002] versus $4483±$16 499 [P<0.001]). All-cause emergency department costs were significantly lower in adherent and intermediate versus nonadherent patients ($499±$1229 and $563±$1292 versus $691±$1652 [P<0.001 and P=0.002], respectively).

CONCLUSIONS

These data suggest clinical and economic benefits of PAP therapy in patients with concomitant OSA and atrial fibrillation. This supports the value of diagnosing and managing OSA and highlights the need for strategies to enhance PAP adherence in this population.

The Role of Risk Factor Modification in Atrial Fibrillation: Outcomes in Catheter Ablation

The management of atrial fibrillation has evolved significantly over the last ten years with advancements in medical and catheter ablation approaches, but these have limited success when used in isolation. Trends in the management of lifestyle modifications have surfaced, as it is now better understood that modifiable risk factors contribute significantly to the development and propagation of atrial fibrillation, as well as failure of treatment. International guidelines have integrated the role of lifestyle modification in the management of atrial fibrillation and specifically in the persistent form of atrial fibrillation; these guidelines must be addressed prior to considering catheter ablation. Effective risk factor modification is critical in increasing the likelihood of an arrhythmia-free survival following catheter ablation.

2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2024 AHA Statistical Update is the product of a full year's worth of effort in 2023 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. The AHA strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional global data, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Atrial fibrillation: stroke prevention

Stroke prevention is central to the management of patients with atrial fibrillation (AF) which has moved towards a more holistic or integrative care approach. The published evidence suggests that management of AF patients following such a holistic approach based on the Atrial fibrillation Better Care (ABC) pathway is associated with a lower risk of stroke and adverse events. Risk assessment, re-assessment and use of direct oral anticoagulants (DOACs) are important for stroke prevention in AF. The stroke and bleeding risks of AF patients are not static and should be re-assessed regularly. Bleeding risk assessment is to address and mitigate modifiable bleeding risk factors, and to identify high bleeding risk patients for early review and follow-up. Well-controlled comorbidities and healthy lifestyles also play an important role to achieve a better clinical outcome. Digital health solutions are increasingly relevant in the diagnosis and management of patients with AF, with the potential to improve stroke prevention. In this review, we provide an update on stroke prevention in AF, including importance of holistic management, risk assessment/re-assessment, and stroke prevention for special AF populations. Evidence-based and structured management of AF patients would reduce the risk of stroke and other adverse events.

Sex-based differences in obstructive sleep apnea and atrial fibrillation: Implication of atrial fibrillation burden

Background

Obstructive sleep apnea (OSA) is a risk factor for atrial fibrillation (AF); however, it is unclear whether AF increases the risk of OSA. Furthermore, sex differences among patients with both AF and OSA remain unclear. We aimed to determine the association between an increased AF burden and OSA and investigate the differences in clinical characteristics between women and men with AF and OSA.

Methods

This was a descriptive, cross-sectional analysis from a prospective cohort study. Patients with non-valvular AF were recruited from the cardiac electrophysiology clinic of a tertiary center; they underwent a home sleep apnea test and 14-day ambulatory electrocardiography. Moderate-to-severe OSA was defined as an apnea-hypopnea index of ≥15.

Results

Of 320 patients with AF, 53.4% had moderate-to-severe OSA, and the mean body mass index (BMI) was 25.6 kg/m2. Less women (38.2%) had moderate-to-severe OSA than men (59.3%) (p < 0.001). In the multivariate analysis, age, being a man, and BMI were significantly associated with moderate-to-severe OSA. AF burden was associated with moderate-to-severe OSA only in men (odds ratio: 1.008; 95% confidence interval: 1.001-1.014). Women and men with OSA had similar BMI (p = 0.526) and OSA severity (p = 0.754), but women were older than men (70.1 ± 1.3 vs. 63.1 ± 0.9 years, p < 0.001). Women with moderate-to-severe OSA had a lower AF burden than men did (27.6 ± 7.1 vs. 49.5 ± 3.9%, p = 0.009).

Conclusions

AF burden is a sex-specific risk factor for OSA and is limited to men. In contrast, women with both AF and OSA have a lower AF burden than men, despite being older and having similar OSA severity and body habitus. Thus, AF may develop later in women with OSA than in men.

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.

Obstructive sleep apnea severity and prevalent atrial fibrillation in a sleep clinic cohort with versus without excessive daytime sleepiness

BACKGROUND

Obstructive sleep apnea (OSA) is associated with atrial fibrillation (AF) in cardiac cohorts. Less is known regarding the magnitude of this association in a sleep clinic cohort with vs. without excessive daytime sleepiness (EDS).

OBJECTIVES

To explore the association of OSA severity with AF in a sleep clinic cohort stratified by EDS.

PATIENTS AND METHODS

All consecutive adults (n = 3814) admitted to the Skaraborg Hospital, Sweden between Jan 2005 and December 2011 were registered in a local database, and the follow-up ended in December 2018. OSA was defined as an apnea-hypopnea index (AHI) ≥5 events/h. Mild OSA was defined as AHI ≥5 & AHI<15 events/h; moderate OSA as AHI ≥15 & AHI<30 events/h; and severe OSA as AHI ≥30 events/h. EDS was defined as an Epworth Sleepiness Scale score ≥11. We conducted cross-sectional analyzes of the prevalent AF across the OSA severity categories and logistic regression analyzes stratified by EDS.

RESULTS

In all, 202 patients (5.3%) had AF at baseline, 1.6% in no-OSA, 3.9% in mild OSA, 5.2% in moderate OSA, and 7.6% in severe OSA, respectively (p < 0.001). The stratified analyzes revealed that patients with severe OSA without EDS had an increased risk for prevalent AF (OR 2.54, 95% CI 1.05-6.16; p = 0.039) independent of the confounding factors.

CONCLUSIONS

There was an independent dose-response relationship between OSA and prevalent AF among the non-sleepy phenotype in this sleep clinic cohort. Since adherence to OSA treatment is challenging in the absence of EDS, these patients may have increased risk for adverse cardiovascular outcomes.

Obstructive sleep apnea in the patient with atrial fibrillation: current knowledge and remaining uncertainties

PURPOSE OF REVIEW

Obstructive sleep apnea (OSA) is highly prevalent in patients with atrial fibrillation and plays a causal role for OSA in the pathogenesis of atrial fibrillation. The presence of OSA in atrial fibrillation is associated with increased symptom burden and increased risk of hospitalizations. Furthermore, untreated OSA is associated with an increased risk of atrial fibrillation recurrence post ablation or cardioversion, and observational studies suggest that continuous positive airway pressure (CPAP) therapy can attenuate this risk. This review describes our current understanding of the relationship between OSA and atrial fibrillation with an emphasis on emerging evidence.

RECENT FINDINGS

Recent studies have identified novel screening questionnaires, which may be superior to traditional questionnaires in identifying OSA in atrial fibrillation populations. Significant night-to-night variability in OSA severity has been shown in atrial fibrillation patients, which has implications for diagnostic testing. While several small, randomized control trials (RCTs) have not shown CPAP therapy to be effective in reducing atrial fibrillation burden, one RCT did show CPAP can attenuate the atrial substrate with implications for long-term outcomes.

SUMMARY

Further RCTs, appropriately powered, and focused on well defined cohorts, are required to guide management decisions regarding screening and treatment of OSA in atrial fibrillation populations.

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.

Breathless nights and heart flutters: Understanding the relationship between obstructive sleep apnea and atrial fibrillation

There is an extraordinary and increasing global burden of atrial fibrillation (AF) and obstructive sleep apnea (OSA), two conditions that frequently accompany one another and that share underlying risk factors. Whether a causal pathophysiologic relationship connects OSA to the development and/or progression of AF, or whether shared risk factors promote both conditions, is unproven. With increasing recognition of the importance of controlling AF-related risk factors, numerous observational studies now highlight the potential benefits of OSA treatment in AF-related outcomes. Physicians are regularly faced with caring for this important and increasing population of patients despite a paucity of clinical guidance on the topic. Here, we review the clinical epidemiology and pathophysiology of AF and OSA with a focus on key clinical studies and major outstanding questions that should be addressed in future studies.

Atrial fibrillation and stroke prevention: 25 years of research at EP Europace journal

Stroke prevention in patients with atrial fibrillation (AF) is one pillar of the management of this common arrhythmia. Substantial advances in the epidemiology and associated pathophysiology underlying AF-related stroke and thrombo-embolism are evident. Furthermore, the introduction of the non-vitamin K antagonist oral anticoagulants (also called direct oral anticoagulants) has clearly changed our approach to stroke prevention in AF, such that the default should be to offer oral anticoagulation for stroke prevention, unless the patient is at low risk. A strategy of early rhythm control is also beneficial in reducing strokes in selected patients with recent onset AF, when compared to rate control. Cardiovascular risk factor management, with optimization of comorbidities and attention to lifestyle factors, and the patient's psychological morbidity are also essential. Finally, in selected patients with absolute contraindications to long-term oral anticoagulation, left atrial appendage occlusion or exclusion may be considered. The aim of this state-of-the-art review article is to provide an overview of the current status of AF-related stroke and prevention strategies. A holistic or integrated care approach to AF management is recommended to minimize the risk of stroke in patients with AF, based on the evidence-based Atrial fibrillation Better Care (ABC) pathway, as follows: A: Avoid stroke with Anticoagulation; B: Better patient-centred, symptom-directed decisions on rate or rhythm control; C: Cardiovascular risk factor and comorbidity optimization, including lifestyle changes.

Molecular mechanisms of postoperative atrial fibrillation in patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) promotes atrial remodeling and fibrosis, providing a substrate for atrial fibrillation (AF). Herein, we investigate the pathophysiological mechanisms of AF in association with OSA in a cohort of cardiac surgery patients. A prospective study including patients undergoing cardiac surgery. Biomarkers reflective of AF pathophysiology (interleukin [IL-6], C-reactive protein [CRP], von Willebrand factor [vWF], N-terminal pro-brain natriuretic peptide [NT-proBNP], high-sensitivity Troponin T [hs-TnT], and Galectin-3 [Gal-3]) was assessed by functional or immunological assays. miRNAs involved in AF were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Using atrial tissue samples, fibrosis was assessed by Masson's trichrome. Connexin 40 and 43 (Cx40; Cx43) were evaluated by immunolabeling. Fifty-six patients (15 with OSA and 41 non-OSA) were included in this hypothesis-generating pilot study. OSA group had a higher incidence of postoperative AF (POAF) (46.7% vs. 19.5%; p = .042), presented an increased risk of POAF (OR 3.61, 95% CI 1.01-12.92), and had significantly higher baseline levels of NT-proBNP (p = .044), vWF (p = .049), Gal-3 (p = .009), IL-6 (p = .002), and CRP (p = .003). This group presented lower levels of miR-21 and miR-208 (both p < .05). Also, lower Cx40 levels in POAF and/or OSA patients (50.0% vs. 81.8%, p = .033) were found. The presence of interstitial fibrosis (according to myocardial collagen by Masson's trichrome) was raised in OSA patients (86.7% vs. 53.7%, p = .024). Several biomarkers and miRNAs involved in inflammation and fibrosis were dysregulated in OSA patients, which together with a higher degree of interstitial fibrosis, altered miRNA, and Cxs expression predisposes to the development of a substrate that increases the AF risk.

The effect of CPAP therapy on heart rate variability in patients with obstructive sleep apnea

The aim of this study was to analyze the relationship between the initiation of CPAP therapy and HRV in patients with OSA. The study group consisted of 37 patients, aged 34-79 (mean 54.95 years) with OSA treated with CPAP. Two subgroups of patients were distinguished: less than severe (AHI < 30, n = 16) and severe OSA (AHI ≥ 30, n = 21). The second study was carried out around a month after the initiation of therapy. CPAP therapy caused the improvement in polysomnographic parameters, however, in most parameters in time and frequency analysis, there were no significant positive changes in parasympathetic tone. Moreover, in HRV time analysis, the reduced rMSSD and pNN50 parameters in the hours of night rest and rMSSD and SDSD during the 15-min N3 sleep period were noted. Especially, in the group with AHI ≥ 30, we observed significant decreases in rMSSD and pNN50 for the entire time. The changes were mainly for the night periods including the N3 sleep period, which is especially connected with sleep apnea (parameters: rMSSD, SDSD, and pNN50). In spectral analysis, the decrease in HF from the 15-min daily activity period and the N3 sleep period was observed. Inverse correlations were seen between the maximum, median, and mean positive airway pressure (PAP) and the change in rMSSD, SDNN, and SDSD, mainly during night hours and the N3 sleep period. Only in patients with AHI < 30 the increase in SDNN was observed in 15-min N3 sleep period. The beneficial increase in SDNN parameter from time analysis was observed only in one sleep period in less ill patients with OSA. The lack of significant changes was observed in the majority of the parameters of heart rate variability after initiation of CPAP therapy in a short observational time; however, the shift towards reduced HRV was observed in patients with AHI > 30, so the response to CPAP therapy may depends on the severity of the apnea. The results may suggest that a longer observational period is needed in such studies, and the problem is still not fully elucidated.

CaMKII-Dependent Contractile Dysfunction and Pro-Arrhythmic Activity in a Mouse Model of Obstructive Sleep Apnea

Left ventricular contractile dysfunction and arrhythmias frequently occur in patients with sleep-disordered breathing (SDB). The CaMKII-dependent dysregulation of cellular Ca homeostasis has recently been described in SDB patients, but these studies only partly explain the mechanism and are limited by the patients' heterogeneity. Here, we analyzed contractile function and Ca homeostasis in a mouse model of obstructive sleep apnea (OSA) that is not limited by confounding comorbidities. OSA was induced by artificial tongue enlargement with polytetrafluorethylene (PTFE) injection into the tongue of wildtype mice and mice with a genetic ablation of the oxidative activation sites of CaMKII (MMVV knock-in). After eight weeks, cardiac function was assessed with echocardiography. Reactive oxygen species (ROS) and Ca transients were measured using confocal and epifluorescence microscopy, respectively. Wildtype PTFE mice exhibited an impaired ejection fraction, while MMVV PTFE mice were fully protected. As expected, isolated cardiomyocytes from PTFE mice showed increased ROS production. We further observed decreased levels of steady-state Ca transients, decreased levels of caffeine-induced Ca transients, and increased pro-arrhythmic activity (defined as deviations from the diastolic Ca baseline) only in wildtype but not in MMVV PTFE mice. In summary, in the absence of any comorbidities, OSA was associated with contractile dysfunction and pro-arrhythmic activity and the inhibition of the oxidative activation of CaMKII conveyed cardioprotection, which may have therapeutic implications.

Epidemiology and modifiable risk factors for atrial fibrillation

The global prevalence of atrial fibrillation (AF) has increased substantially over the past three decades and is currently approximately 60 million cases. Incident AF and its clinical consequences are largely the result of risk factors that can be modified by lifestyle changes. In this Review, we provide evidence that the lifetime risk of AF is modified not only by sex and race but also through the clinical risk factor and comorbidity burden of individual patients. We begin by summarizing the epidemiology of AF, focusing on non-modifiable and modifiable risk factors, as well as targets and strategies for the primary prevention of AF. Furthermore, we evaluate the role of modifiable risk factors in the secondary prevention of AF as well as the potential effects of risk factor interventions on the frequency and severity of subsequent AF episodes. We end the Review by proposing strategies that require evaluation as well as global policy changes that are needed for the prevention of incident AF and the management of recurrent episodes in patients already affected by AF.

Screening for Obstructive Sleep Apnea in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Obstructive sleep apnea (OSA) is associated with adverse health outcomes.

OBJECTIVE

To review the evidence on screening for OSA in asymptomatic adults or those with unrecognized OSA symptoms to inform the US Preventive Services Task Force.

DATA SOURCES

PubMed/MEDLINE, Cochrane Library, Embase, and trial registries through August 23, 2021; surveillance through September 23, 2022.

STUDY SELECTION

English-language studies of screening test accuracy, randomized clinical trials (RCTs) of screening or treatment of OSA reporting health outcomes or harms, and systematic reviews of treatment reporting changes in blood pressure and apnea-hypopnea index (AHI) scores.

DATA EXTRACTION AND SYNTHESIS

Dual review of abstracts, full-text articles, and study quality. Meta-analysis of intervention trials.

MAIN OUTCOMES AND MEASURES

Test accuracy, excessive daytime sleepiness, sleep-related and general health-related quality of life (QOL), and harms.

RESULTS

Eighty-six studies were included (N = 11 051). No study directly compared screening with no screening. Screening accuracy of the Multivariable Apnea Prediction score followed by unattended home sleep testing for detecting severe OSA syndrome (AHI ≥30 and Epworth Sleepiness Scale [ESS] score &gt;10) measured as the area under the curve in 2 studies (n = 702) was 0.80 (95% CI, 0.78 to 0.82) and 0.83 (95% CI, 0.77 to 0.90). Five studies assessing the accuracy of other screening tools were heterogeneous and results were inconsistent. Compared with inactive control, positive airway pressure was associated with a significant improvement in ESS score from baseline (pooled mean difference, -2.33 [95% CI, -2.75 to -1.90]; 47 trials; n = 7024), sleep-related QOL (standardized mean difference, 0.30 [95% CI, 0.19 to 0.42]; 17 trials; n = 3083), and general health-related QOL measured by the 36-Item Short Form Health Survey (SF-36) mental health component summary score change (pooled mean difference, 2.20 [95% CI, 0.95 to 3.44]; 15 trials; n = 2345) and SF-36 physical health component summary score change (pooled mean difference, 1.53 [95% CI, 0.29 to 2.77]; 13 trials; n = 2031). Use of mandibular advancement devices was also associated with a significantly larger ESS score change compared with controls (pooled mean difference, -1.67 [95% CI, 2.09 to -1.25]; 10 trials; n = 1540). Reporting of other health outcomes was sparse; no included trial found significant benefit associated with treatment on mortality, cardiovascular events, or motor vehicle crashes. In 3 systematic reviews, positive airway pressure was significantly associated with reduced blood pressure; however, the difference was relatively small (2-3 mm Hg).

CONCLUSIONS AND RELEVANCE

The accuracy and clinical utility of OSA screening tools that could be used in primary care settings were uncertain. Positive airway pressure and mandibular advancement devices reduced ESS score. Trials of positive airway pressure found modest improvement in sleep-related and general health-related QOL but have not established whether treatment reduces mortality or improves most other health outcomes.

Obesity as a risk factor for cardiac arrhythmias

Obesity is global health problem with an estimated three billion people worldwide being classified as overweight or obese. In addition to being associated with a range of adverse health outcomes, obesity is linked to higher risks of atrial and ventricular arrhythmias, as well as sudden cardiac death. Obesity is a multifactorial disease that often co-exists with hypertension, diabetes, and sleep apnoea, which are also independent risk factors for cardiac arrhythmias. Nevertheless, compelling evidence suggests that increasing adiposity is an independent proarrhythmic risk factor and that weight loss can be a mitigating and preventative intervention to reduce arrhythmia incidence. This review briefly outlines the economic and social burden of obesity and summarises evidence for the direct and indirect effects of increasing adiposity on risk of atrial and ventricular arrhythmias. The paper also summarises the evidence for electrocardiographic changes indicative of obesity-related atrial and ventricular remodelling and how weight reduction and management of comorbidity might reduce arrhythmic burden.

Vagal milieu or electrophysiologic substrate? The link between atrial fibrillation and obstructive sleep apnea

Atrial fibrillation is the most common cardiac arrhythmia with its prevalence expected to increase to 12.1 million people in the United States by 2030. Chronic underlying conditions that affect the heart and lungs predispose patients to develop atrial fibrillation. Obstructive sleep apnea is strongly associated with atrial fibrillation. Several pathophysiological mechanisms have been proposed to elucidate this relationship which includes electrophysiological substrate modification and the contribution of the autonomic nervous system. In this comprehensive review, we highlight important relationships and plausible causality between obstructive sleep apnea and atrial fibrillation which will improve our understanding in the evaluation, management, and prevention of atrial fibrillation. This is the most updated comprehensive review of the relationship between obstructive sleep apnea and atrial fibrillation.

Obstructive sleep apnea and its management in patients with atrial fibrillation: An International Collaboration of Sleep Apnea Cardiovascular Trialists (INCOSACT) global survey of practicing cardiologists

Background

Among international cardiologists it is unclear whether equipoise exists regarding the benefit of diagnosing and managing obstructive sleep apnea (OSA) to improve atrial fibrillation (AF) outcomes and whether clinical practice and equipoise are linked.

Methods

Between January 2019 and June 2020 we distributed a web-based 12-question survey regarding OSA and AF management to practicing cardiologists in 16 countries.

Results

The United States, Japan, Sweden, and Turkey accounted for two-thirds of responses. 863 cardiologists responded; half were general cardiologists, a quarter electrophysiologists. Responses regarding treating OSA with CPAP to improve AF endpoints were mixed. 33% of respondents referred AF patients for OSA screening. OSA was diagnosed in 48% of referred patients and continuous positive airway pressure (CPAP) was prescribed for 59% of them. Nearly 70% of respondents believed randomized controlled trials (RCTs) of OSA treatment in AF patients were necessary and indicated willingness to contribute to such trials.

Conclusions

There was no clinical equipoise among surveyed cardiologists; a majority expressed certainty that combined OSA and AF treatment is superior to AF treatment alone for improving AF outcomes. However, a minority of surveyed cardiologists referred AF patients for OSA testing, and while half of screened AF patients had OSA, CPAP was prescribed in little more than half of them, reflecting the view that better clinical trial evidence is needed to support this practice. Our results underscore the need for larger, multi-national prospective studies of OSA treatment and AF outcomes to inform more uniform society guideline recommendations.

Sleep-Disordered Breathing and Cardiac Arrhythmias in Adults: Mechanistic Insights and Clinical Implications: A Scientific Statement From the American Heart Association

Sleep-disordered breathing (SDB), characterized by specific underlying physiological mechanisms, comprises obstructive and central pathophysiology, affects nearly 1 billion individuals worldwide, and is associated with excessive cardiopulmonary morbidity. Strong evidence implicates SDB in cardiac arrhythmogenesis. Immediate consequences of SDB include autonomic nervous system fluctuations, recurrent hypoxia, alterations in carbon dioxide/acid-base status, disrupted sleep architecture, and accompanying increases in negative intrathoracic pressures directly affecting cardiac function. Day-night patterning and circadian biology of SDB-induced pathophysiological sequelae collectively influence the structural and electrophysiological cardiac substrate, thereby creating an ideal milieu for arrhythmogenic propensity. Cohort studies support strong associations of SDB and cardiac arrhythmia, with evidence that discrete respiratory events trigger atrial and ventricular arrhythmic events. Observational studies suggest that SDB treatment reduces atrial fibrillation recurrence after rhythm control interventions. However, high-level evidence from clinical trials that supports a role for SDB intervention on rhythm control is not available. The goals of this scientific statement are to increase knowledge and awareness of the existing science relating SDB to cardiac arrhythmias (atrial fibrillation, ventricular tachyarrhythmias, sudden cardiac death, and bradyarrhythmias), synthesizing data relevant for clinical practice and identifying current knowledge gaps, presenting best practice consensus statements, and prioritizing future scientific directions. Key opportunities identified that are specific to cardiac arrhythmia include optimizing SDB screening, characterizing SDB predictive metrics and underlying pathophysiology, elucidating sex-specific and background-related influences in SDB, assessing the role of mobile health innovations, and prioritizing the conduct of rigorous and adequately powered clinical trials.

Obstructive Sleep Apnea and Cardiovascular Diseases: Sad Realities and Untold Truths regarding Care of Patients in 2022

Obstructive sleep apnea (OSA) is one of the most common and serious sleep-related breathing disorders with a high prevalence among patients with cardiovascular (CV) diseases. Despite its widespread presence, OSA remains severely undiagnosed and untreated. CV mortality and morbidity are significantly increased in the presence of OSA as it is associated with an increased risk of resistant hypertension, heart failure, arrhythmias, and coronary artery disease. Evaluation and treatment of OSA should focus on recognizing patients at risk of developing OSA. The use of screening questionnaires should be routine, but a formal polysomnography sleep study is fundamental in establishing and classifying OSA. Recognition of OSA patients will allow for the institution of appropriate therapy that should alleviate OSA-related symptoms with the intent of decreasing adverse CV risk. In this review, we focus on the impact OSA has on CV disease and evaluate contemporary OSA treatments. Our goal is to heighten awareness among CV practitioners.

Intermittent Hypoxia-Induced Cardiomyocyte Death Is Mediated by HIF-1 Dependent MAM Disruption

Rationale: Intermittent hypoxia (IH) is one of the main features of sleep-disordered breathing (SDB). Recent findings indicate that hypoxia inducible factor-1 (HIF-1) promotes cardiomyocytes apoptosis during chronic IH, but the mechanisms involved remain to be elucidated. Here, we hypothesize that IH-induced ER stress is associated with mitochondria-associated ER membrane (MAM) alteration and mitochondrial dysfunction, through HIF-1 activation. Methods: Right atrial appendage biopsies from patients with and without SDB were used to determine HIF-1α, Grp78 and CHOP expressions. Wild-type and HIF-1α^+/− mice were exposed to normoxia (N) or IH (21–5% O₂, 60 cycles/h, 8 h/day) for 21 days. Expressions of HIF-1α, Grp78 and CHOP, and apoptosis, were measured by Western blot and immunochemistry. In isolated cardiomyocytes, we examined structural integrity of MAM by proximity ligation assay and their function by measuring ER-to-mitochondria Ca²⁺ transfer by confocal microscopy. Finally, we measured mitochondrial respiration using oxygraphy and calcium retention capacity (CRC) by spectrofluorometry. MAM structure was also investigated in H9C2 cells incubated with 1 mM CoCl₂, a potent HIF-1α inducer. Results: In human atrial biopsies and mice, IH induced HIF-1 activation, ER stress and apoptosis. IH disrupted MAM, altered Ca²⁺ homeostasis, mitochondrial respiration and CRC. Importantly, IH had no effect in HIF-1α^+/− mice. Similar to what observed under IH, HIF-1α overexpression was associated with MAM alteration in H9C2. Conclusion: IH-induced ER stress, MAM alterations and mitochondrial dysfunction were mediated by HIF-1; all these intermediate mechanisms ultimately inducing cardiomyocyte apoptosis. This suggests that HIF-1 modulation might limit the deleterious cardiac effects of SDB.

Management of Atrial Fibrillation Across the Spectrum of Heart Failure With Preserved and Reduced Ejection Fraction

Atrial fibrillation (AF) is the most common arrhythmia among patients with heart failure (HF), and HF is the most common cause of death for patients presenting with clinical AF. AF is frequently associated with pathological atrial myocardial dysfunction and remodeling, a triad that has been called atrial myopathy. AF can be the cause or consequence of clinical HF, and the directionality varies between individual patients and across the spectrum of HF. Although initial trials suggested no advantage for a systematic rhythm control strategy in HF with reduced ejection fraction, recent data suggest that select patients may benefit from attempts to maintain sinus rhythm with catheter ablation. Preliminary data also show a close relationship among AF, left atrial myopathy, mitral regurgitation, and HF with preserved ejection, with potential clinical benefits to catheter ablation therapy. The modern management of AF in HF also requires consideration of the degree of atrial myopathy and chronicity of AF, in addition to the pathogenesis and phenotype of the underlying left ventricular HF. In this review, we summarize the contemporary management of AF and provide practical guidance and areas in need of future investigation.

Effect of continuous positive airway pressure therapy on recurrence of atrial fibrillation after pulmonary vein isolation in patients with obstructive sleep apnea: A randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) is associated with atrial fibrillation (AF). It is unknown whether treatment with continuous positive airway pressure (CPAP) reduces AF recurrence after catheter ablation with pulmonary vein isolation (PVI).

OBJECTIVE

We aimed to assess the effect of CPAP treatment on the recurrence and burden of AF after PVI in patients with OSA.

METHODS

We randomized patients with paroxysmal AF and an apnea-hypopnea index (AHI) ≥15 events/h to treatment with CPAP or standard care. Heart rhythm was monitored by an implantable loop recorder. AF recurrence after PVI was defined as any episode of AF lasting more than 2 minutes after a 3-month blanking period.

RESULTS

PVI was performed in 83 patients. 37 patients were randomized to CPAP treatment and 46 patients to standard care. The AHI was reduced from 26.7 ± 14 to 1.7 ± 1.3 events/h at follow-up in the CPAP group (P = .001). 57 % of patients in both the CPAP group and the standard care group had at least one episode of AF 3-12 months after PVI (P for difference = 1.00). AF burden after ablation was reduced in both groups, with no between-group difference (P = .69).

CONCLUSION

In patients with paroxysmal AF and OSA, treatment with CPAP did not further reduce the risk of AF recurrence after ablation. PVI considerably reduced the burden of AF in OSA-patients, without any difference between the groups.

Enhanced Cardiac CaMKII Oxidation and CaMKII-Dependent SR Ca Leak in Patients with Sleep-Disordered Breathing

Background: Sleep-disordered breathing (SDB) is associated with increased oxidant generation. Oxidized Ca/calmodulin kinase II (CaMKII) can contribute to atrial arrhythmias by the stimulation of sarcoplasmic reticulum Ca release events, i.e., Ca sparks. Methods: We prospectively enrolled 39 patients undergoing cardiac surgery to screen for SDB and collected right atrial appendage biopsies. Results: SDB was diagnosed in 14 patients (36%). SDB patients had significantly increased levels of oxidized and activated CaMKII (assessed by Western blotting/specific pulldown). Moreover, SDB patients showed a significant increase in Ca spark frequency (CaSpF measured by confocal microscopy) compared with control subjects. CaSpF was 3.58 ± 0.75 (SDB) vs. 2.49 ± 0.84 (no SDB) 1/100 µm⁻¹s⁻¹ (p < 0.05). In linear multivariable regression models, SDB severity was independently associated with increased CaSpF (B [95%CI]: 0.05 [0.03; 0.07], p < 0.001) after adjusting for important comorbidities. Interestingly, 30 min exposure to the CaMKII inhibitor autocamtide-2 related autoinhibitory peptide normalized the increased CaSpF and eliminated the association between SDB and CaSpF (B [95%CI]: 0.01 [−0.1; 0.03], p = 0.387). Conclusions: Patients with SDB have increased CaMKII oxidation/activation and increased CaMKII-dependent CaSpF in the atrial myocardium, independent of major clinical confounders, which may be a novel target for treatment of atrial arrhythmias in SDB.

Sleep apnea and atrial fibrillation: challenges in clinical and translational research

INTRODUCTION

Sleep-disordered breathing (SDB) is present in 21-74% of all patients with atrial fibrillation (AF). Treatment of SDB by positive airway pressure may help to prevent recurrence of AF after electrical cardioversion and help to improve AF ablation success rates in non-randomized studies.

AREAS COVERED

In this review, the current understanding of the atrial arrhythmogenic pathophysiology of SDB is summarized, and diagnostic and therapeutic challenges in AF patients are discussed. Current international recommendations are presented, and a comprehensive literature search is undertaken.

EXPERT OPINION

AF patients with SDB rarely report SDB-related symptoms such as daytime sleepiness. Therefore, systematic home sleep testing evaluation should be considered for all patients eligible for rhythm control strategy. A close interdisciplinary collaboration between the electrophysiologist/cardiologist, nurses and sleep-specialists are required for the management of SDB in AF patients. An arrhythmia-orientated assessment of SDB may better quantify SDB-related AF risk in an individual patient and may help to better guide targeted and personalized SDB treatment in AF patients as a component of rhythm and symptom control strategies. Finally, randomized controlled trials are needed to confirm the relationship between SDB and AF, and the benefits of routine testing and treatment of SDB in AF patients.

Sleep Disordered Breathing, Obesity and Atrial Fibrillation: A Mendelian Randomisation Study

It remains unclear whether the association between obstructive sleep apnoea (OSA), a form of sleep-disordered breathing (SDB), and atrial fibrillation (AF) is causal or mediated by shared co-morbidities such as obesity. Existing observational studies are conflicting and limited by confounding and reverse causality. We performed Mendelian randomisation (MR) to investigate the causal relationships between SDB, body mass index (BMI) and AF. Single-nucleotide polymorphisms associated with SDB (n = 29) and BMI (n = 453) were selected as instrumental variables to investigate the effects of SDB and BMI on AF, using genetic association data on 55,114 AF cases and 482,295 controls. Primary analysis was conducted using inverse-variance weighted MR. Higher genetically predicted SDB and BMI were associated with increased risk of AF (OR per log OR increase in snoring liability 2.09 (95% CI 1.10-3.98), p = 0.03; OR per 1-SD increase in BMI 1.33 (95% CI 1.24-1.42), p < 0.001). The association between SDB and AF was not observed in sensitivity analyses, whilst associations between BMI and AF remained consistent. Similarly, in multivariable MR, SDB was not associated with AF after adjusting for BMI (OR 0.68 (95% CI 0.42-1.10), p = 0.12). Higher BMI remained associated with increased risk of AF after adjusting for OSA (OR 1.40 (95% CI 1.30-1.51), p < 0.001). Elevated BMI appears causal for AF, independent of SDB. Our data suggest that the association between SDB, in general, and AF is attributable to mediation or confounding from obesity, though we cannot exclude that more severe SDB phenotypes (i.e., OSA) are causal for AF.

Obstructive sleep apnea

Obstructive sleep apnea (OSA) is a disease that results from loss of upper airway muscle tone leading to upper airway collapse during sleep in anatomically susceptible persons, leading to recurrent periods of hypoventilation, hypoxia, and arousals from sleep. Significant clinical consequences of the disorder cover a wide spectrum and include daytime hypersomnolence, neurocognitive dysfunction, cardiovascular disease, metabolic dysfunction, respiratory failure, and pulmonary hypertension. With escalating rates of obesity a major risk factor for OSA, the public health burden from OSA and its sequalae are expected to increase, as well. In this chapter, we review the mechanisms responsible for the development of OSA and associated neurocognitive and cardiometabolic comorbidities. Emphasis is placed on the neural control of the striated muscles that control the pharyngeal passages, especially regulation of hypoglossal motoneuron activity throughout the sleep/wake cycle, the neurocognitive complications of OSA, and the therapeutic options available to treat OSA including recent pharmacotherapeutic developments.

Sleep Apnoea and Heart Failure

Heart Failure (HF) and Sleep-Disordered-Breathing (SDB) are two common conditions that frequently overlap and have been studied extensively in the past three decades. Obstructive Sleep Apnea (OSA) may result in myocardial damage, due to intermittent hypoxia increased sympathetic activity and transmural pressures, low-grade vascular inflammation and oxidative stress. On the other hand, central sleep apnoea and Cheyne-Stokes respiration (CSA-CSR) occurs in HF, irrespective of ejection fraction either reduced (HFrEF), preserved (HFpEF) or mildly reduced (HFmrEF). The pathophysiology of CSA-CSR relies on several mechanisms leading to hyperventilation, breathing cessation and periodic breathing. Pharyngeal collapse may result at least in part from fluid accumulation in the neck, owing to daytime fluid retention and overnight rostral fluid shift from the legs. Although both OSA and CSA-CSR occur in HF, the symptoms are less suggestive than in typical (non-HF related) OSA. Overnight monitoring is mandatory for a proper diagnosis, with accurate measurement and scoring of central and obstructive events, since the management will be different depending on whether the sleep apnea in HF is predominantly OSA or CSA-CSR. SDB in HF are associated with worse prognosis, including higher mortality than in patients with HF but without SDB. However, there is currently no evidence that treating SDB improves clinically important outcomes in patients with HF, such as cardiovascular morbidity and mortality.

Central Sleep Apnea Is Associated with an Abnormal P-Wave Terminal Force in Lead V1 in Patients with Acute Myocardial Infarction Independent from Ventricular Function

Sleep-disordered breathing (SDB) is highly prevalent in patients with cardiovascular disease. We have recently shown that an elevation of the electrocardiographic (ECG) parameter P wave terminal force in lead V₁ (PTFV₁) is linked to atrial proarrhythmic activity by stimulation of reactive oxygen species (ROS)-dependent pathways. Since SDB leads to increased ROS generation, we aimed to investigate the relationship between SDB-related hypoxia and PTFV₁ in patients with first-time acute myocardial infarction (AMI). We examined 56 patients with first-time AMI. PTFV₁ was analyzed in 12-lead ECGs and defined as abnormal when ≥4000 µV*ms. Polysomnography (PSG) to assess SDB was performed within 3–5 days after AMI. SDB was defined by an apnea-hypopnea-index (AHI) >15/h. The multivariable regression analysis showed a significant association between SDB-related hypoxia and the magnitude of PTFV₁ independent from other relevant clinical co-factors. Interestingly, this association was mainly driven by central but not obstructive apnea events. Additionally, abnormal PTFV₁ was associated with SDB severity (as measured by AHI, B 21.495; CI [10.872 to 32.118]; p < 0.001), suggesting that ECG may help identify patients suitable for SDB screening. Hypoxia as a consequence of central sleep apnea may result in atrial electrical remodeling measured by abnormal PTFV₁ in patients with first-time AMI independent of ventricular function. The PTFV₁ may be used as a clinical marker for increased SDB risk in cardiovascular patients.

A VIRTUAL Sleep Apnoea management pathway For the work-up of Atrial fibrillation patients in a digital Remote Infrastructure: VIRTUAL-SAFARI

AIMS

In atrial fibrillation (AF) patients, untreated sleep-disordered breathing (SDB) is associated with lower success rates of rhythm control strategies and as such structured SDB testing is recommended. Herein, we describe the implementation of a virtual SDB management pathway in an AF outpatient clinic and examine the utility and feasibility of this new approach.

METHODS AND RESULTS

Prospectively, consecutive AF patients accepted for AF catheter ablation procedures without previous diagnosis of SDB were digitally referred to a virtual SDB management pathway and instructed to use WatchPAT-ONE (ITAMAR) for one night. Results were automatically transferred to a virtual sleep laboratory, upon which a teleconsultation with a sleep physician was planned. Patient experience was measured using surveys. SDB testing was performed in 119 consecutive patients scheduled for AF catheter ablation procedures. The median time from digital referral to finalization of the sleep study report was 18 [11-24] days. In total, 65 patients (55%) were diagnosed with moderate-to-severe SDB. Patients with SDB were prescribed more cardiovascular drugs and had higher body mass indices (BMI, 29 ± 3.3 vs. 27 ± 4.4kg/m2, P < 0.01). Patients agreed that WatchPAT-ONE was easy to use (91%) and recommended future use of this virtual pathway in AF outpatient clinics (86%). Based on this remote SDB testing, SDB treatment was recommended in the majority of patients.

CONCLUSION

This novel virtual AF management pathway allowed remote SDB testing in AF outpatient clinics with a short time to diagnosis and high patient satisfaction. Structured SDB testing results in a high detection of previously unknown SDB in AF patients scheduled for AF ablation.

Obstructive Sleep Apnea and Cardiac Arrhythmias: A Contemporary Review

Obstructive sleep apnea (OSA) is a highly prevalent disorder with a growing incidence worldwide that closely mirrors the global obesity epidemic. OSA is associated with enormous healthcare costs in addition to significant morbidity and mortality. Much of the morbidity and mortality related to OSA can be attributed to an increased burden of cardiovascular disease, including cardiac rhythm disorders. Awareness of the relationship between OSA and rhythm disorders is variable among physicians, a fact that can influence patient care, since the presence of OSA can influence the incidence, prevalence, and successful treatment of multiple rhythm disorders. Herein, we provide a review of this topic that is intentionally broad in scope, covering the relationship between OSA and rhythm disorders from epidemiology and pathophysiology to diagnosis and management, with a particular focus on the recognition of undiagnosed OSA in the general clinical population and the intimate relationship between OSA and atrial fibrillation.