Cardiac rhythm disturbances in the obstructive sleep apnea syndrome: effects of nasal continuous positive airway pressure therapy

Obstructive Sleep Apnea - Influence on the Cardiovascular System and Cognition

Kardiovaskuläre und kognitive Erkrankungen sind ebenso wie die obstruktive Schlafapnoe sehr häufige Krankheiten mit einer erheblichen Beeinträchtigung der Lebensqualität und einer deutlichen sozioökonomischen Bedeutung. Die Auswirkungen einer unbehandelten obstruktiven Schlafapnoe (OSA) auf das kardiovaskuläre und kognitive Erkrankungsrisiko und die Therapieeffekte einer OSA sind für die meisten kardiovaskulären und kognitiven Folgeerkrankungen wissenschaftlich nachgewiesen. Für die klinische Praxis besteht ein deutlicher Bedarf nach mehr Interdisziplinarität. Aus schlafmedizinischer Sicht müssen bei der Therapieindikation das individuelle kardiovaskuläre und kognitive Risiko berücksichtigt und kognitive Erkrankungen bei der Beurteilung der Therapieintoleranz und residuellen Symptomatik beachtet werden. Aus internistischer Sicht sollte bei Patienten mit schlecht einstellbarem Hypertonus, Vorhofflimmern, koronarer Herzkrankheit und Schlaganfall die Abklärung einer OSA in die Diagnostik integriert werden. Bei Patienten mit milder kognitiver Beeinträchtigung, Alzheimer-Krankheit und Depression können sich die typischen Symptome wie Fatigue, Tagesmüdigkeit und Reduktion der kognitiven Leistungen mit OSA-Symptomen überschneiden. Die Diagnostik einer OSA sollte in die Abklärung dieser Krankheitsbilder integriert werden, da eine Therapie der OSA die kognitiven Beeinträchtigungen reduzieren und die Lebensqualität verbessern kann.

Interaction of positive airway pressure mask magnets with cardiac implantable electronic devices

STUDY OBJECTIVES

To evaluate for potential interactions between magnetic positive airway pressure (mPAP) masks and cardiac implantable electronic devices (CIEDs) for patients with sleep apnea.

METHODS

Adult patients with a CIED who used an mPAP mask were recruited from our sleep clinic to undergo a safety visit at our pacemaker clinic. We tested whether the mPAP interacted with the implanted device at home during normal use and in the clinic during simulated normal use and with direct contact. The magnetic field strength of 6 mPAP masks was tested with a gaussmeter.

RESULTS

Of 13 patients tested, 1 (8%), wearing a full face mask (ResMed AirFit F30 [ResMed, San Diego, California]), had a magnet response event (interaction) with direct contact, but no interactions were identified during normal or simulated normal use in any patient. The magnetic field strength of the mPAP masks increased the closer the mask got to the CIED, from 0.4 mT (4 G) at the mask manufacturer's recommended 5.1-cm (2-inch) distance from an implanted medical device up to 291 mT (2,910 G) at 0 cm (0 inches; direct contact).

CONCLUSIONS

An mPAP mask may interact with a CIED if placed directly on the skin overlying the CIED. The use of Philips Respironics (Philips, Cambridge, Massachusetts) mPAP masks is now contraindicated in patients with a CIED. Until additional studies are conducted to better document the risks and benefits of mPAP masks, we recommend discouraging patients with CIEDs from using any mPAP mask.

CITATION

Ruoff CM, Tashman YS, Cheema KPK, et al. Interaction of positive airway pressure mask magnets with cardiac implantable electronic devices. J Clin Sleep Med. 2023;19(5):941-946.

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.

Clinical outcomes and plaque characteristics in patients with coronary artery disease and concomitant sleep-disordered breathing treated by continuous positive airway pressure

BACKGROUND

Sleep-disordered breathing (SDB) is a risk factor for recurrent adverse events in patients with coronary artery disease (CAD). However, the prognosis of continuous positive alveolar pressure (CPAP) treatment for SDB with CAD remains unknown.

METHODS

A total of 281 consecutive patients with stable CAD requiring percutaneous coronary intervention (PCI) were included and classified into three groups according to the concomitance of SDB and CPAP treatment (untreated SDB group, n = 61; CPAP-SDB group, n = 24; and non-SDB group, n = 138). The incidence of major adverse cardiac and cerebrovascular events (MACCEs) within a year after PCI was compared between the three groups. The characteristics of the culprit plaques, including macrophage accumulation, were further assessed using optical coherence tomography.

RESULTS

The incidence of MACCEs was significantly different among the three groups (p = 0.037), with the highest incidence in the untreated-SDB group (22.9%) and 8.3% and 10.1% in the CPAP-SDB and non-SDB groups, respectively. The incidence of MACCEs at 1 year was significantly lower in patients with appropriate CPAP use than that in inadequately treated patients with SDB (0.0 vs. 22.5%, p = 0.048). Macrophage accumulation differed significantly among the three groups, with the highest accumulation in the untreated SDB group.

CONCLUSIONS

CPAP treatment for SDB may be associated with a lower incidence of MACCEs following PCI and a lower prevalence of macrophages in the culprit plaques.

Alcohol intake and bradyarrhythmia risk: a cohort study of 407 948 individuals

AIMS 

There is a paucity of epidemiological evidence on alcohol and the risk of bradyarrhythmias. We thus characterized associations of total and beverage-specific alcohol consumption with incident bradyarrhythmias using data from the UK Biobank.

METHODS AND RESULTS 

Alcohol consumption reported at baseline was calculated as UK standard drinks (8 g alcohol)/week. Bradyarrhythmia events were defined as sinus node dysfunction (SND), high-level atrioventricular block (AVB), and permanent pacemaker implantations. Outcomes were assessed through hospitalization and death records, and dose-response associations were characterized using Cox regression models with correction for regression dilution bias. We studied 407 948 middle-aged individuals (52.4% female). Over a median follow-up time of 11.5 years, a total of 8 344 incident bradyarrhythmia events occurred. Increasing total alcohol consumption was not associated with an increased risk of bradyarrhythmias. Beer and cider intake were associated with increased bradyarrhythmia risk up to 12 drinks/week; however, no significant associations were observed with red wine, white wine, or spirit intake. When bradyarrhythmia outcomes were analysed separately, a negative curvilinear was observed for total alcohol consumption and risk of SND, but no clear association with AVB was observed.

CONCLUSION 

In this predominantly White British cohort, increasing total alcohol consumption was not associated with an increased risk of bradyarrhythmias. Associations appeared to vary according to the type of alcoholic beverage and between different types of bradyarrhythmias. Further epidemiological and experimental studies are required to clarify these findings.

Prevalence, types and treatment of bradycardia in obstructive sleep apnea - A systematic review and meta-analysis

BACKGROUND

The association of obstructive sleep apnea (OSA) with bradycardia is not well-characterized, which may confer significant morbidity and mortality if left untreated. We sought to clarify the prevalence of comorbid OSA and bradycardia, and the effect of continuous positive airway pressure (CPAP) therapy on bradycardia outcomes.

METHODS

We systematically searched four electronic databases (PubMed, Embase, Cochrane Library, Scopus) for randomized or observational studies reporting the co-prevalence of sleep apnea and bradycardia or evaluated the use of CPAP on the incidence of bradycardias. We used random-effects models in all meta-analyses and evaluated heterogeneity using I².

RESULTS

We included 34 articles from 7204 records, comprising 4852 patients. Among patients with OSA, the pooled prevalence of daytime and nocturnal bradycardia were 25% (95% CI: 18.6 to 32.7) and 69.8% (95% CI: 41.7 to 88.2) respectively. Among patients with bradycardia, the pooled prevalence of OSA was 56.8% (95% CI: 21.5 to 86.3). CPAP treatment, compared to those without, did not significantly reduce the risk of daytime (two randomized trials; RR: 0.50; 95% CI: 0.11 to 2.21) or nocturnal bradycardia (one randomized-controlled trial and one cohort study; RR: 0.76; 95% CI: 0.48 to 1.20).

CONCLUSIONS

This meta-analysis demonstrates a high comorbid disease burden between OSA and bradycardia. Future research should explore the treatment effect of CPAP on bradycardia incidence, as compared to placebo.

Ventrikuläre Arrhythmien bei obstruktiver und zentraler Schlafapnoe

Hintergrund

Ventrikuläre Arrhythmien treten mit einer hohen Prävalenz auf und sind mit einer hohen Morbidität und Mortalität assoziiert. Sowohl die obstruktive (OSA) als auch die zentrale (ZSA) Schlafapnoe können auf Grund ihrer Pathophysiologie zu vermehrten ventrikulären Arrhythmien beitragen.

Ziel

Dieser Artikel soll die komplexen Zusammenhänge und Erkenntnisse jüngster Forschungen bezüglich schlafbezogenen Atmungsstörungen (SBAS) und ventrikulärer Arrhythmien und deren Therapiemöglichkeiten beleuchten.

Material und Methoden

Es erfolgte eine Literaturrecherche basierend auf prospektiven, retrospektiven, klinischen und experimentellen Studien sowie Reviews, Metaanalysen und aktuellen Leitlinien, die seit 2014 in der Medline-Datenbank gelistet wurden.

Ergebnisse

Es besteht ein bidirektionaler Zusammenhang zwischen der SBAS und ventrikulären Arrhythmien. Intermittierende Hypoxie, oxidativer Stress, wiederkehrende Arousals, intrathorakale Druckschwankungen und kardiales Remodeling tragen im Rahmen der SBAS zu einer erhöhten ventrikulären Arrhythmieneigung bei. Der Schweregrad der OSA, gemessen mittels Apnoe-Hypopnoe-Index, ist mit der Prävalenz ventrikulärer Arrhythmien assoziiert. Ähnliche Ergebnisse liegen für Patienten mit ZSA und Herzinsuffizienz vor. Studien zu ventrikulären Arrhythmien bei ZSA-Patienten ohne Herzinsuffizienz fehlen. Eine Positivdrucktherapie (PAP) bei OSA- oder ZSA-Patienten führte in verschiedenen Studien zu einer reduzierten Anzahl an ventrikulären Arrhythmien. Dieser Zusammenhang konnte jedoch nicht in allen Studien bestätigt werden. Ventrikuläre Arrhythmien treten bei der OSA gehäuft nachts auf, bei der ZSA gleichmäßig über den Tag verteilt.

Diskussion

Bisherige Studien weisen einen Zusammenhang zwischen der OSA bzw. der ZSA und ventrikulären Arrhythmien trotz unterschiedlicher Pathophysiologie nach. Hinsichtlich des Effektes der PAP auf ventrikuläre Arrhythmien bei Patienten mit OSA und ZSA sind weitere Studien erforderlich.

Positionspapier „Schlafmedizin in der Kardiologie“, Update 2021

Es hat sich viel getan in der Welt der Schlafmedizin in der Kardiologie, weshalb eine vollwertige Überarbeitung des Positionspapiers „Schlafmedizin in der Kardiologie“ erforderlich wurde. In der aktuellen neuartigen Version finden sich nicht nur alle verfügbaren Studien, Literaturstellen und Updates zu Pathophysiologie, Diagnostik- und Therapieempfehlungen, sondern auch Ausblicke auf neue Entwicklungen und zukünftige Forschungserkenntnisse. Dieses überarbeitete Positionspapier gibt Empfehlungen für Diagnostik und Therapie von Patienten mit kardiovaskulären Erkrankungen mit schlafassoziierten Atmungsstörungen und erteilt darüber hinaus einen fundierten Überblick über verfügbare Therapien und Evidenzen, gibt aber ebenso Ratschläge wie mit Komorbiditäten umzugehen ist. Insbesondere enthält dieses überarbeitete Positionspapier aktualisierte Stellungnahmen zu schlafassoziierten Atmungsstörungen bei Patienten mit koronarer Herzerkrankung, Herzinsuffizienz, arterieller Hypertonie, aber auch für Patienten mit Vorhofflimmern. Darüber hinaus finden sich erstmals Empfehlungen zur Telemedizin als eigenes, neues Kapitel. Dieses Positionspapier bietet Kardiologen sowie Ärzten in der Behandlung von kardiovaskulären Patienten die Möglichkeit einer evidenzbasierten Behandlung der wachsend bedeutsamen und mit zunehmender Aufmerksamkeit behafteten Komorbidität schlafassoziierter Atmungsstörungen. Und nicht zuletzt besteht mit diesem neuen Positionspapier eine enge Verknüpfung mit dem neuen Curriculum Schlafmedizin der Deutschen Gesellschaft für Kardiologie, weshalb dieses Positionspapier eine Orientierung für die erworbenen Fähigkeiten des Curriculums im Umgang von kardiovaskulären Patienten mit schlafassoziierten Atmungsstörungen darstellt.

Obstructive Sleep Apnea and Cardiovascular Disease

Obstructive sleep apnea (OSA) presents as repetitive interruptions of ventilation >10 seconds during sleep as a result of upper airway obstruction resulting in increased respiratory effort. Intermittent hypoxia causes physiologic changes resulting in increased catecholamine production, increased total peripheral resistance, tachycardia, and increased venous return, leading to increased cardiac output, hypertension, tachyarrhythmias, left ventricular hypertrophy, and heart failure. OSA causes an abnormal dip on 24-hour ambulatory blood pressure monitoring. Definitive diagnosis is made by polysomnography. Continuous positive airway pressure (CPAP) remains the first-line treatment. Effective treatment using CPAP reduces blood pressure and is indispensable for proper management of atrial fibrillation.

Correlation between apnea-hypopnea index and Tp-Te interval, Tp-Te/QT, and Tp-Te/QTc ratios in obstructive sleep apnea

Background

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder associated with important cardiovascular complications including ventricular arrhythmias. Tp‐Te interval, Tp‐Te/QT, and Tp‐Te/QTc ratios are repolarization indices representing ventricular arrhythmogenic potential. These parameters are associated with ventricular arrhythmias and sudden cardiac death. The aim of this study was to investigate the correlation between apnea–hypopnea index and Tp‐Te, Tp‐Te/QT, and Tp‐Te/QTc in OSA.

Methods

We screened a total of 280 patients who underwent overnight polysomnography (PSG) between the years 2012–2017 at our institution. Patients were assigned into four groups based on severity of apnea–hypopnea index: 70 with apnea–hypopnea index (AHI) <5 (control group), 71 with 5 ≤ AHI < 15, 63 with 15 ≤ AHI < 30, and 76 with AHI ≥ 30. Tp‐Te, Tp‐Te/QT, and Tp‐Te/QTc were measured.

Results

Compared to control group, repolarization parameters were significantly prolonged in other groups (Tp‐Te interval: 68.3 ± 6.8, 71.8 ± 6.3, 79.1 ± 5.5, and 85.1 ± 6.4 ms, p < .001; Tp‐Te/QT ratio: 167.5 ± 12.7, 181.7 ± 13.0, 202.2 ± 10.0 and 219.4 ± 13.5, p < .001; Tp‐Te/QTc ratio: 151.1 ± 16.6, 167.6 ± 16.6, 193.7 ± 14.4, and 225.5 ± 17.0, p < .001). There was a significant trend toward higher Tp‐Te, Tp‐Te/QT, and Tp‐Te/QTc across higher AHI categories. In a univariate regression analysis, body mass index, smoking status, Tp‐Te, and Tp‐Te/QTc were significantly associated with the severity of AHI in OSA. Tp‐Te (OR 1.629, 95% CI 1.393–1.906, p < .001), Tp‐Te/QTc (OR 1,333 95% CI 1.247–1.424, p < .001), and smoking status (OR 5.771, 95% CI 1.025–32.479, p = .047) were found to be significant independent predictors of severity of AHI in a multivariate analysis, after adjusting for other risk parameters.

Conclusions

Our study showed that Tp‐Te, Tp‐Te/QT, and Tp‐Te/QTc were prolonged in patients with OSA. There was significant correlation between apnea–hypopnea index and these parameters.

[Adherence and efficacy of long-term PAP therapy in patients with sleep-related breathing disorders associated with cardiac conduction disorders]

AIM

To study the effectiveness of prolonged use of PAP therapy (positive airway pressure therapy) in eliminating sleep respiratory disorders and associated cardiac conduction disturbances.

MATERIALS AND METHODS

We included 21 patients who were examined at the Myasnikov Institute of Clinical Cardiology, National Medical Research Center of Cardiology, regarding cardiac rhythm and conduction disturbances, as well as obstructive sleep apnea and who have been on PAP therapy for more than 12 months. The average age was 66.5 [63.5; 73.2] years, body mass index 33.0 [30.2; 38.5] kg/m2, apnea-hypopnea index 65.0 [59.0; 86.3]/h. At the time of analysis, 15 patients continued to use PAP therapy (mean time of use: 6.0 years [4.7; 9.2]) and 6 patients refused long-term use of PAP therapy, mean time to use PAP therapy until failure amounted to 2.82.1 years.

RESULTS

PAP therapy lead to a persistent decrease in apnea-hypopnea index of 63.6/h to 3.7/h was (p=0.0002). 86% of patients met the criteria for adherence to PAP therapy (use 4 hours/night, more than 70% of nights). Initially, before the use of PAP therapy, all cardiac conduction disorders were during sleep and exceeded 3 seconds, with fluctuations from 3.1 to 10.6 seconds. PAP therapy appeared to be effective in all patients: no asystoles, duration of more than 3 seconds, were detected.

CONCLUSION

In obstructive sleep apnea patients with concomitant nighttime cardiac conduction disturbances, the long-term use of PAP therapy is effective and with good adherence.

Obstructive Sleep Apnea: Risk Factor for Arrhythmias, Conduction Disorders, and Cardiac Arrest

Background Obstructive sleep apnea (OSA) has been described as a risk factor for cardiac arrhythmias. Its association with atrial fibrillation has been established. However, relationships with other arrhythmias and conduction disorders have not been fully studied. Methods We used the National Inpatient Sample database from 2009 to 2011 to explore the relationship between OSA and arrhythmias and conduction disorders. The presence of diagnosis was determined based on the International Classification of Disease-9 (ICD-9) codes. Univariate and multivariate logistic regressions were used to establish mortality risks among all groups. Results Multivariate logistic regression showed increased mortality in patients with OSA in comparison to patients without OSA and patients across all categories of arrhythmias and conduction disorders. One significant finding was the increased association of cardiac arrest in patients with OSA versus patients without OSA (OR: 95.72; CI: 89.13-105.81, p < 0.001). Conclusions OSA is significantly associated with non-atrial fibrillation arrhythmias, conduction disorders, and sudden cardiac arrest. Awareness regarding this association is important for early screening for OSA in obese patients to prevent cardiovascular morbidity and mortality. The use of continuous positive airway pressure (CPAP) might be beneficial against all kinds of arrhythmias and sudden cardiac death.

The Converging Pathologies of Obstructive Sleep Apnea and Atrial Arrhythmias

Obstructive sleep apnea (OSA) is highly prevalent in the United States (US). Along with epidemic rates of obesity, the rate of OSA cases is also on the rise. OSA is associated with multiple chronic health conditions, including hypertension, diabetes, stroke, myocardial ischemia, and heart rhythm disturbances. OSA is commonly treated with continuous positive airway pressure (CPAP) therapy. Several reports indicate that effective treatment of OSA can reduce the risk of cardiovascular diseases, including cardiac arrhythmias, especially atrial fibrillation (AF). CPAP therapy helps to maintain sinus rhythm after interventions such as electrical cardioversion and catheter ablation in patients with AF. However, more data is required to establish a relationship between OSA and other atrial arrhythmias as well to evaluate the effect of CPAP. This review will compile the latest evidence on the pathophysiology, management, and treatment of atrial arrhythmias associated with OSA.

Reducing cost and time to diagnosis and treatment of obstructive sleep apnea using ambulatory sleep study: a Singapore sleep centre experience

PURPOSE

The current gold standard for diagnosis of obstructive sleep apnea (OSA) is overnight in laboratory polysomnography (PSG). However, PSGs are expensive, labor-intensive, and have long wait times. An ambulatory sleep study device, the WatchPAT, has been shown to have high correlation for sleep indices measured compared with PSG (AASM, 2016). Use of the WatchPAT could potentially lead to shorter waiting times and earlier diagnosis of OSA (Lancet Resp Med 3:310-8, 2015). Our study aimed to investigate if WatchPAT reduces time to diagnosis and treatment of OSA in a tertiary healthcare setting. A secondary aim was to investigate the cost-benefit of an ambulatory sleep study.

METHODS

All patients who underwent diagnostic sleep studies in a single tertiary institution from 2014 to 2017 were retrospectively reviewed. Baseline characteristics and time from ordering of sleep study to prescription of continuous positive airway pressure were recorded. Data were categorized into two groups by type of diagnostic sleep study, PSG, and WatchPAT. The time to treatment and cost for diagnosis of OSA were compared between groups with the Paired T test/Wilcoxon signed-rank test.

RESULTS

Of 1898 patients who had diagnostic sleep studies over a 4-year period, 1660 patients (88%) underwent PSG and 238 patients (12%) underwent WatchPAT. Patients in the WatchPAT group had a shorter time to diagnosis (21 days versus 79.8 days, p < 0.001) and treatment (46.3 days versus 118.4 days, p < 0.001) compared to the PSG group. Cost-benefit calculation showed that this earlier treatment led to cost-saving of US $1179.50 per patient.

CONCLUSION

An ambulatory sleep study is an option for earlier access to diagnosis and treatment of OSA with the potential of considerable cost savings.

The Association Between Obstructive Sleep Apnea and Arrhythmias

Obstructive sleep apnea (OSA) is caused by intermittent episodes of partial or complete closure of the upper airway, leading to apneic episodes while the patient is asleep. Atrial fibrillation (AF) leads to more than 750,000 hospitalizations per year and accounts for an estimated 130,000 deaths each year. The death rate from AF as the primary or a contributing cause of death has been rising for more than two decades. The material reviewed in this paper focuses on the association between OSA and arrhythmias. It goes into the details of the epidemiology, pathophysiology, and types of arrhythmias and the therapies seen in association with OSA.

Ventricular Arrhythmias in Patients with Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) is a prevalent condition thought to increase in the future. Being mostly undiagnosed, the most serious complications are cardiovascular diseases, among which are arrhythmias. Controversy remains as to whether OSA is a primary etiologic factor for ventricular arrhythmias, because of the high incidence of cardiovascular comorbidities in OSA patients. Howev-er, there is mostly a strong evidence of a relation between OSA and ventricular arrhythmias. A few mechanisms have been proposed to be responsible for this association and some electrocardiographic changes have also been demonstrated to be more frequent in OSA patients. Treatment of OSA with Continuous Positive Airway Pressure (CPAP) has the potential to reduce arrhythmias and confer a mortality benefit.

Cardiovascular outcomes of continuous positive airway pressure therapy for obstructive sleep apnea

Obstructive sleep apnea is a common disorder with increased risk for cardiovascular morbidity and mortality. The first choice of treatment of obstructive sleep apnea is continuous positive airway pressure, which reduces excessive daytime sleepiness and improves quality of life in sleep clinic cohorts. Nevertheless, the majority of patients with cardiovascular disease and concomitant obstructive sleep apnea do not report daytime sleepiness, and adherence to treatment is insufficient particularly in this group. The current article aims to give an updated overview of the impact of continuous positive airway pressure therapy on cardiovascular outcomes mainly based on the observational studies and the recent randomized controlled trials.

Cardiac effects of CPAP treatment in patients with obstructive sleep apnea and atrial fibrillation

PURPOSE

Obstructive sleep apnea (OSA) has been recognized as an independent risk factor for the development and progression of atrial fibrillation (AF). We aimed to investigate the changes in heart rate and atrial and ventricular ectopy after continuous positive airway pressure (CPAP) treatment in patients with OSA and AF.

METHODS

Consecutive patients with AF underwent ambulatory sleep monitoring, and OSA was defined as an Apnea-Hypopnea-Index (AHI) ≥ 5/h. Treated patients completed in-laboratory CPAP titration study. A 24-h ECG Holter was performed at baseline and at 3 and 6 months after CPAP treatment.

RESULTS

One hundred patients (70% males) with AF were included in the final analysis. OSA was diagnosed in 85% of patients. There were no significant changes in mean 24-h heart rate in patients with paroxysmal or permanent AF at 3 and 6 months of treatment compared to baseline. In patients with paroxysmal AF (n = 29), atrial and ventricular ectopy counts/24 h significantly decreased at 3 months compared to baseline (median (IQR) 351 (2049) to 57 (182), P = 0.002; 68 (105) to 16 (133), P = 0.01 respectively). At 6 months follow-up, the atrial ectopy count/24 h significantly decreased in patients with paroxysmal AF compared to baseline (median (IQR) 351 (2049) to 31 (113), P = 0.016, n = 14). In patients with permanent AF (n = 15), there was a significant reduction in ventricular ectopy count/24 h at 3 months compared to baseline (median (IQR) 100 (1116) to 33 (418), P = 0.02).

CONCLUSIONS

There is a significant decrease in atrial and ventricular ectopy count/24 h in patients with AF and OSA at 3 and 6 months of CPAP treatment compared to baseline.

Obstructive sleep apnoea-hypopnoea and arrhythmias: new updates

AIMS

Obstructive sleep apnoea-hypopnoea (OSAH) is a prevalent condition characterized by repetitive pharyngeal collapse during sleep, leading to hypoxemia, hypercapnia, and persistent inspiratory efforts against an occluded airway until arousal. Several studies demonstrated that OSAH exerts acute and chronic effects on the cardiovascular system. Thus, although being a respiratory problem, the most important consequences of OSAH are cardiovascular, among which there are arrhythmias. The purpose of this review is to systematically analyse what has been recently published about the relationship between OSAH and every cardiac arrhythmia separately.

METHODS

We searched Pubmed, Scopus, Web of Science and Cochrane Collaboration databases for 'OSAHS arrhythmias', 'OSAH arrhythmias' and 'OSA arrhythmias'. We analyse 1298 articles and meta-analyses, excluding already edited reviews.

RESULTS

Arrhythmias, especially of ventricular origin, are frequent in OSAH. Ventricular premature beats, couplets and ventricular tachycardia runs are even more frequent in patients suffering from heart failure. They may be due to left heart remodelling, overwork and ischaemia and can explain at least some sudden deaths occurring between midnight and 6 a.m. Sinus pauses and atrioventricular blocks are increased according to the severity of the disturbance and may be reduced by continuous positive airway pressure therapy, preventing pace-maker implantation. Finally, atrial fibrillation, resistance against antiarrhythmic drugs and recurrences after surgical procedures are strongly related to OSAH.

CONCLUSION

Arrhythmias are frequent in OSAH. Treatment of OSAH may reduce some of them. An implantable cardioverter-defibrillator and continuous positive airway pressure should be considered in some patients.

Access to CPAP treatment in patients with moderate to severe sleep apnea in a Latin American City

Introduction:

The most effective treatment for moderate to severe obstructive sleep apnea (OSA) is continuous positive airway pressure (CPAP) but adherence may be a limiting factor. Most compliance studies often only include patients under CPAP treatment, neglecting the importance of access to treatment. The aim of this study was to evaluate CPAP access and compliance in OSA patients, after CPAP indication and titration.

Methods:

We included moderate to severe OSA patients, diagnosed by in-lab polysomnography (PSG), with CPAP indication and effective pressure titration. Between 12 to 18 months after treatment was indicated a telephone questionnaire was administered including questions about access to CPAP, reasons of no access, reported adherence and symptoms improvement.

Results:

A total of 213 patients responded to the survey (171 males, mean age 53.4±13.5 and BMI 34.02±8.8 kg/m²). Almost a third of the patients (28.2%) did not initiate CPAP treatment. Out of 213, 153 patients (71.8%) started treatment with CPAP and 120 (56.3%) reported still being under treatment a year after indication, additionally, 85.8% reported that they were using it =4hs/night. Those who accessed to CPAP were on average, older age, had full coverage of treatment by their medical insurance, required lower effective pressure and experienced more severe sleepiness compared to those individuals who did not accessed to CPAP.

Discussion:

A significant proportion of OSA patients with CPAP indication did not initiate and/or eventually abandoned CPAP. Approximately only 50% of the patients were still under treatment, with acceptable self-reported adherence rate and clinical response, one year after the initial treatment indication. Additional measures are necessary to increase access to CPAP and improve long-term compliance.

Screening and managing obstructive sleep apnoea in nocturnal heart block patients: an observational study

Background

Nocturnal heart block often occurs in patients with obstructive sleep apnoea (OSA). It is more likely to be undiagnosed in heart block patients who are ignorant of the symptoms of sleep disorder. Berlin Questionnaire (BQ) is a highly reliable way to discover the risk factors of OSA, whereas the validity in sleep-related heart block patients is uncertain. We performed an observational study to address these issues and confirmed the potential protective effect of continuous positive airway pressure (CPAP).

Methods

Patients who were previously diagnosed with nocturnal heart block with R-R pauses exceeding 2 seconds were retrospective screened from the ECG centre of Zhongshan hospital. These recruited participants completed Berlin Questionnaire and underwent polysomnography synchronously with 24-hour Holter monitoring. A cross-sectional analysis was performed to confirm the association between nocturnal arrhythmia and OSA, as well as to assess the diagnostic accuracy of the BQ. Subsequently, subjects diagnosed with OSA (apnoea-hypopnoea index > 5) underwent 3 consecutive days of CPAP therapy. On the third day, patients repeated 24-hour Holter monitoring within the institution of CPAP.

Results

The symptoms of disruptive snoring and hypersomnolence in 72 enrolled patients were more related to the occurrence of nocturnal heart block (r = 0.306, 0.226, respectively, p = 0.015, 0.019) than syncope (r = 0.134, p = 0.282) and palpitations (r = 0.106, p = 0.119), which were prominent trait of our study population. The sensitivity, specificity, positive and negative predictive value of the BQ at a cut-off point of 5 of AHI for detecting OSA in heart block patients was 81.0 %, 44.4 %, 91.07 % and 25 %. Nocturnal heart block does not appear to occur exclusively in severe sleep apnoea. The frequent occurrence of arrhythmias in prominent oxygen desaturation supports the correlation between them. CPAP therapy resulted in significant decrease in the average number of episodes of heart block, from 148.58 ± 379.44 to 16.07 ± 58.52 (p < 0.05), same to the change of the longest RR pausing time (from 4.38 ± 2.95 s to 0.57 ± 1.05 s, p = 0.169) in 51 patients. The optimal therapy pressure to make the observed arrhythmia disappeared is 12 cm H₂O.

Conclusion

Concerning high prevalence of OSA in heart block patients, BQ provided an economical and efficient screening method for OSA. For better management, CPAP therapy is feasible to prevent heart blocks avoiding unnecessary concomitant pacemaker implantation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-016-0333-8) contains supplementary material, which is available to authorized users.

Clinical manifestations of sleep apnea

Obstructive sleep apnea (OSA) may manifest in a number of ways from subtle intrusion into daily life to profound sleepiness, snoring, witnessed apneas and other classic symptoms. Although there is increasing evidence suggesting OSA can adversely affect health in a variety of ways, this disorder remains underdiagnosed. The most well-escribed health consequences of OSA relate to the cardiovascular system. Hypertension and arrhythmias have a strong association with OSA, and evidence suggests that treatment of OSA in patients with refractory hypertension and in patients planning cardioversion for atrial fibrillation may be of particularly importance. Significant associations between heart failure and OSA as well as complex sleep apnea have also been well-described. Cerebrovascular insult, impaired neurocognition, and poorly controlled mood disorder are also associated with in OSA. Therapy for OSA may ameliorate atherosclerotic progression and improve outcomes post-cerebrovascular accident (CVA). OSA should be considered in patients complaining of poor concentration at work, actual or near-miss motor vehicle accidents, and patients with severe sleepiness as a component of their co-morbid mood disorders. The metabolic impact of OSA has also been studied, particularly in relation to glucose homeostasis. Also of interest is the potential impact OSA has on lipid metabolism. The adverse effect untreated OSA has on glucose tolerance and lipid levels has led to the suggestion that OSA is yet another constituent of the metabolic syndrome. Some of these metabolic derangements may be related to the adverse effects untreated OSA has on hepatic health. The cardiovascular, neurocognitive, and metabolic manifestations of OSA can have a significant impact on patient health and quality of life. In many instances, evidence exists that therapy not only improves outcomes in general, but also modifies the severity of co-morbid disease. To mitigate the long-term sequela of this disease, providers should be aware of the subtle manifestations of OSA and order appropriate testing as necessary.

Trauma and syncope-evidence for further sleep study? A case report

We report on an 83-year-old male with traumatic brain injury after syncope with a fall in the morning. He had a history of seizures, coronary artery disease and paroxysmal atrial fibrillation (AF). No medical cause for seizures and syncope was determined. During rehabilitation, the patient still complained of seizures, and also reported sleepiness and snoring. Sleep apnea diagnostics revealed obstructive sleep apnea (SA) with an apnea-hypopnoea index of 35/h, and sudden onset of tachycardia with variations of heart rate based on paroxysmal atrial fibrillation. Additional tests showed nocturnal AF which spontaneously converted to sinus rhythm mid-morning with an arrest of 5 s (sick sinus syndrome) and seizures. A DDD-pacer was implanted and no further seizures occurred. SA therapy with nasal continuous positive airway pressure was refused by the patient. Our findings suggests that screening for SA may offer the possibility to reveal causes of syncope and may introduce additional therapeutic options as arrhythmia and SA often occur together which in turn might be responsible for trauma due to syncope episodes.

Myotonic dystrophy and the heart: A systematic review of evaluation and management

Myotonic dystrophy (MD) is a multisystem, autosomal dominant disorder best known for its skeletal muscle manifestations. Cardiac manifestations arise as a result of myocardial fatty infiltration, degeneration and fibrosis and present most commonly as arrhythmias or conduction disturbances. Guidelines regarding the optimal cardiac management of patients with MD are lacking. The present article provides a summary of the pathophysiology of cardiac problems in patients with MD and provides a practical approach to contemporary cardiac monitoring and management of these patients with a focus on the prevention of complications related to conduction disturbances and arrhythmias.

METHODS

A literature search was performed using PubMed and Medline. The keywords used in the search included "myotonic dystrophy", "cardiac manifestations", "heart", "arrhythmia", "pacemaker" and "defibrillator", all terms were used in combination. In addition, "myotonic dystrophy" was searched in conjunction with "electrophysiology", "electrocardiogram", "echocardiograph", "signal averaged electrocardiograph", "magnetic resonance imaging" and "exercise stress testing". The titles of all the articles revealed by the search were screened for relevance. The abstracts of relevant titles were read and those articles which concerned the cardiac manifestations of myotonic dystrophy or the investigation and management of cardiac manifestations underwent a full manuscript review.

Effect of obstructive sleep apnoea on severity and short-term prognosis of acute coronary syndrome

The goal of this study was to evaluate the influence of obstructive sleep apnoea on the severity and short-term prognosis of patients admitted for acute coronary syndrome. Obstructive sleep apnoea was defined as an apnoea-hypopnoea index (AHI) >15 h(-1). We evaluated the acute coronary syndrome severity (ejection fraction, Killip class, number of diseased vessels, and plasma peak troponin) and short-term prognosis (length of hospitalisation, complications and mortality). We included 213 patients with obstructive sleep apnoea (mean±sd AHI 30±14 h(-1), 61±10 years, 80% males) and 218 controls (AHI 6±4 h(-1), 57±12 years, 82% males). Patients with obstructive sleep apnoea exhibited a higher prevalence of systemic hypertension (55% versus 37%, p<0.001), higher body mass index (29±4 kg·m(-2) versus 26±4 kg·m(-2), p<0.001), and lower percentage of smokers (61% versus 71%, p=0.04). After adjusting for smoking, age, body mass index and hypertension, the plasma peak troponin levels were significantly elevated in the obstructive sleep apnoea group (831±908 ng·L(-1) versus 987±884 ng·L(-1), p=0.03) and higher AHI severity was associated with an increased number of diseased vessels (p=0.04). The mean length of stay in the coronary care unit was higher in the obstructive sleep apnoea group (p=0.03). This study indicates that obstructive sleep apnoea is related to an increase in the peak plasma troponin levels, number of diseased vessels, and length of stay in the coronary care unit.

Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system. Results: A total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

A systematic review of the association between obstructive sleep apnea and ventricular arrhythmias

INTRODUCTION

Obstructive sleep apnea (OSA) is an independent risk factor for sudden cardiac death. The aim of this review was to study the relationship between OSA and ventricular arrhythmias.

METHODS

PubMed, Medline, and Cochrane databases were searched with MESH headings to find studies linking OSA and ventricular arrhythmias including ventricular ectopy, ventricular tachycardia (VT), and ventricular fibrillation (VF). Studies were graded by a scoring system, and an attempt was made to pool data.

RESULTS

There were no matched cohort or case control studies to study the association between OSA and ventricular arrhythmias. Given data heterogeneity, pooling and meta-analysis of data were not possible. An attempt was made to judge the quality of evidence and present a systematic review. Patients with OSA were noted to have higher odds of ventricular ectopy, and were at a higher risk for ventricular arrhythmias. Associations included higher QTc dispersion and HR variability. We did not, however, find any clear evidence for a direct correlation between increased apnea hypopnea index and increased VT or VF.

CONCLUSIONS

Pooling and meta-analysis of studies linking OSA and ventricular arrhythmias were not possible due to heterogeneity of data. In a systemic review of studies, patients with OSA were noted to have higher odds of ventricular ectopy and arrhythmias. A single study showed that CPAP may help lower arrhythmogenicity; however, it was unclear if CPAP lowered the risk of VT. Further research should focus on studying the association of OSA and causes of sudden cardiac death, including ventricular arrhythmias.