Treatment Of Central Sleep Apnea Research Articles

Central sleep apnea in chronic heart failure with hypoxemia - treatment efficacy and hemodynamic effects of three different treatment modalities: a case report

BackgroundThe optimal treatment for central sleep apnea (CSA) depends on the underlying pathophysiology and should consider the potential for hemodynamic impairment when using positive airway pressure devices. While the long-term effects on overall cardiovascular outcome have been investigated for different device settings, the immediate hemodynamic consequences are not well understood. This is mainly due to a lack of hemodynamic monitoring during routine polysomnographic assessment. The application of most monitoring devices is either restricted by their invasiveness, e.g. in thermodilution, or cannot be used continuously like in echocardiography. Impedance cardiography (ICG), however, enables physicians to implement a continuous non-invasive monitoring of different hemodynamic parameters which can be useful in various clinical scenarios. In sleep medicine, the hemodynamic effect of initiating positive airway pressure treatment in patients with pre-existing heart failure should be of special concern.Case presentationIn this case report, we compare the efficacy of three different treatment modalities in a patient with CSA related to chronic heart failure considering the resolution of respiratory events on polysomnography (PSG). In addition, we outline the hemodynamic effects of each treatment device using ICG for non-invasive hemodynamic monitoring. Regarding the reduction of respiratory central events, long-term oxygen treatment (LTOT) and adaptive servoventilation (ASV) proved to be more efficient compared with automatic positive airway pressure (APAP). Hemodynamically, substantial differences of the cardiac performance were observed between the treatment devices. This especially applied to ASV which led to a pronounced drop in cardiac output.ConclusionOur case report indicates that treatment of CSA may induce significant changes of hemodynamic parameters which would remain undetected during routine polysomnographic assessment. We conclude that non-invasive hemodynamic monitoring may be considered when positive airway pressure treatment is initiated in patients at risk of hemodynamic impairment.

Diagnostic and therapeutic process of respiratory disorders during sleep

Introduction and purpose Sleep apnea is a disturbance of sleep that affects about 10% of adult population and is not easily detected due to unspecific symptoms. The aim of this literature review is to present, respectively, obstructive sleep apnea and central sleep apnea symptoms and integrate the available data in the literature regarding the pathogenesis and treatment methods. Materials and methods A review of literature was performed using PubMed and Google Scholar database. The search criteria included keywords such as sleep apnea, obstructive sleep apnea treatment, central sleep apnea treatment. State of knowledge Sleep disturbances that involve breathing can be categorized as obstructive sleep apnea (OSA) and central sleep apnea. First one is associated with the obstruction of the upper airways and the second one – with malfunctioning breathing generator in the pontomedullary breathing pacemaker. Symptoms are unspecific which makes diagnostic process difficult. However, the right diagnosis and treatment may prevent patients from developing many cardiovascular diseases. Treatment options for OSA include: CPAP, reducing body weight, changing sleep position, braces and surgeries; for CSA: CPAP and acetazolamide. Conclusions OSA and CSA need to be further investigated in order to find more precise ways of diagnosis and treatment, as these diseases remain underreported. It is worth noting, that these conditions predispose to serious diseases, e.g. stroke. Therefore, developing new treatment techniques would beneficial for the health of population.

Phrenic nerve stimulation for the treatment of central sleep apnea in patients with heart failure

Phrenic nerve stimulation for the treatment of central sleep apnea in patients with heart failure

ДИХАЛЬНІ РОЗЛАДИ ПІД ЧАС СНУ У ДОРОСЛИХ: ТЕМИ ПОТОЧНИХ НАУКОВИХ ДОСЛІДЖЕНЬ ТА ОСНОВНІ ОНОВЛЕННЯ ПРАКТИЧНИХ РЕКОМЕНДАЦІЙ

Respiratory disorders during sleep are an urgent and multifaceted problem of clinical medicine, in which the insufficient practical implementation of medical care for patients does not correspond to fundamental scientific achievements. The aim of this review was to assess the significant updates of practical recommendations for the diagnosis and treatment of sleep-disordered breathing in adults. The global lack of practical success in the treatment of patients with sleep-related breathing disorders supports the high relevance of the problem and prompts new research in pathology (biomarkers, structural disorders, risk factors, etc.) and modification of devices for diagnosis and therapy. Today, the classification of sleep-related breathing disorders has been updated. The functional criteria of polysomnography in determining ventilation disorders have been clarified. Diagnostic criteria for disorders associated with obstructive and central sleep apnea have undergone minor changes. Updated practice guidelines for obstructive sleep apnea include failure of CPAP therapy, revised indications for positional therapy, and upper airway or bariatric surgery. Updates in the treatment of central sleep apnea relate to the functional state of the heart and the type of respiratory disorder. In heart failure with a reduced ejection fraction adaptive servo-ventilation is contraindicated, in hypercapnia and/or hypoventilation during the rapid phase of sleep non-invasive lung ventilation is required. Current updates recommend positive airway pressure therapy (CPAP-therapy for concomitant severe obstructive sleep apnea) in stable outpatients with obesity-hypoventilation syndrome, and noninvasive ventilation in hospitalized patients with respiratory failure. General approaches to treatment remain constant: ventilatory disorders require appropriate mechanical correction. Key words: sleep-related breathing disorders, obstructive sleep apnea, central sleep apnea.

Transvenous phrenic nerve stimulation for treating central sleep apnea may regulate sleep microstructure

Study objectivesTo assess the impact of transvenous phrenic nerve stimulation (TPNS) on non-rapid eye movement sleep microstructure quantified by cyclic alternating pattern (CAP) in individuals with central sleep apnea (CSA). MethodsWe analyzed baseline and 6-month follow-up overnight polysomnograms (PSG) in 134 CSA patients enrolled in the remedē System Pivotal Trial implanted with TPNS randomized (1:1) to neurostimulation (treatment group) or no stimulation (control group). Differences in CAP rate, A1 index, and A2+A3 index between study arms at follow-up were assessed using Analysis of Covariance adjusted for baseline values. ResultsOn follow-up PSG, the treatment group showed a decrease in the frequency of A2+A3 phases compared to controls (−5.86 ± 11.82 vs. 0.67 ± 15.25, p = 0.006), while the frequency of A1 phases increased more in the treatment group (2.57 ± 11.67 vs. −2.47 ± 10.60, p = 0.011). The change in CAP rate at follow-up was comparable between study arms. ConclusionsTPNS treatment for central sleep apnea may affect sleep microstructure. Brief phases of rapid cortical activity appear to be replaced by short phases of slower cortical activity, which may promote sleep continuity. Further investigations are warranted to elucidate the mechanisms underlying the effect of TPNS on CAP.

Central sleep apnea treated by a constant low-dose CO2 supplied by a novel device.

CO2 inhalation has been previously reported as a treatment for central sleep apnea both when associated with heart failure or where the cause is unknown. Here, we evaluated a novel CO2 supply system using a novel open mask capable of comfortably delivering a constantly inspired fraction of CO2 ([Formula: see text]) during sleep. We recruited 18 patients with central sleep apnea (13 patients with cardiac disease, and 5 patients idiopathic) diagnosed by diaphragm electromyogram (EMG) recordings made during overnight full polysomnography (PSG) (night 1). In each case, the optimal [Formula: see text] was determined by an overnight manual titration with PSG (night 2). Titration commenced at 1% CO2 and increased by 0.2% increments until central sleep apnea (CSA) disappeared. Patients were then treated on the third night (night 3) with the lowest therapeutically effective concentration of CO2 derived from night 2. Comparing night 1 and night 3, both apnea-hypopnea index (AHI; 31 ± 14 vs. 6 ± 3 events/h, P < 0.01) and arousal index (22 ± 8 vs. 15 ± 8 events/h, P < 0.01) were significantly improved during CO2 treatment. Sleep efficiency improved from 71 ± 18 to 80 ± 11%, P < 0.05, and sleep latency was shorter (23 ± 18 vs. 10 ± 10 min, P < 0.01). Heart rate was not different between night 1 and night 3. Our data confirm the feasibility of our CO2 delivery system and indicate that individually titrated CO2 supplementation with a novel device including a special open mask can reduce sleep disordered breathing severity and improve sleep quality. Randomized controlled studies should now be undertaken to assess therapeutic benefit for patients with CSA.NEW & NOTEWORTHY A novel device using a special mask was developed and proved that CO2 therapy using the device could eliminate central sleep apnea (CSA) events and improve sleep quality including reducing arousal index in patients with heart failure. The device would become a useful clinical treatment for heart failure patients with CSA.

Phrenic nerve stimulation for treatment of central sleep apnea

The prevalence of central sleep apnea (CSA) is rare in general population. However, CSA is prevalent in those with cardiovascular and cerebrovascular disorders. CSA may persist or even worsen with positive airway pressure therapy in some patients and phrenic nerve stimulation (PNS) offers an alternative treatment for patients with CSA. The device is implanted similar to a cardiac pacemaker and typically followed in the sleep clinic. Multiple studies have described the efficacy and safety of PNS. Improvements were seen in apnea hypopnea events, central events, arousals, and daytime sleepiness and maintained through 5 years. Safety demonstrated a 91% freedom from serious adverse events through 1 year. The physiologic approach and improvement in sleep metrics and quality of life with a strong safety profile make this therapy a good option for many patients with central sleep apnea.

Analysis by sex of safety and effectiveness of transvenous phrenic nerve stimulation

PurposeLittle is known about sex differences in the treatment of central sleep apnea (CSA). Our post hoc analysis of the remedē System Pivotal Trial aimed to determine sex-specific differences in the safety and effectiveness of treating moderate to severe CSA in adults with transvenous phrenic nerve stimulation (TPNS).MethodsMen and women enrolled in the remedē System Pivotal Trial were included in this post hoc analysis of the effect of TPNS on polysomnographic measures, Epworth Sleepiness Scale, and patient global assessment for quality of life.ResultsWomen (n = 16) experienced improvement in CSA metrics that were comparable to the benefits experienced by men (n = 135), with central apneas being practically eliminated post TPNS. Women experienced improvement in sleep quality and architecture that was comparable to men post TPNS. While women had lower baseline apnea hypopnea index than men, their quality of life was worse at baseline. Additionally, women reported a 25-percentage point greater improvement in quality of life compared to men after 12 months of TPNS therapy. TPNS was found to be safe in women, with no related serious adverse events through 12 months post-implant, while men had a low rate of 10%.ConclusionAlthough women had less prevalent and less severe CSA than men, they were more likely to report reduced quality of life. Transvenous phrenic nerve stimulation may be a safe and effective tool in the treatment of moderate to severe CSA in women. Larger studies of women with CSA are needed to confirm our findings.Clinical trial registrationClinicalTrials.gov NCT01816776; March 22, 2013.

PO-04-076 PHRENIC NERVE STIMULATOR LEAD MIGRATION RESULTING IN ATRIAL DYSRHYTHMIA

The phrenic nerve stimulator (PNS) is a novel treatment for central sleep apnea (CSA). The device (Remede, Respicardia Inc) consists of a pulse generator and a lead positioned in the left pericardiophrenic or right brachiocephalic vein. This stimulates the phrenic nerve during sleep resulting in diaphragmatic contraction to restore normal breathing. We report a case of PNS lead migration into the right atrium resulting in atrial dysrhythmias during device stimulation. N/A An 83 year old female with history of ischemic cardiomyopathy status post primary prevention ICD, and severe CSA underwent PNS placement two years ago with the pacing lead in the right brachiocephalic vein. Due to ongoing dyspnea and LBBB she had an upgrade to CRT-D using an epicardial LV lead. Post operatively she developed palpitations with several recorded episodes of wide complex tachycardia (image 1a). Interrogation of her CRT showed nocturnal atrial arrhythmias with aberrancy seemingly triggered by rhythmic electrical interference on her atrial marker channels (image 1b). There were no recorded daytime episodes. When interrogating the CRT-D with the PNS turned on, atrial arrhythmias were reproduced by periods of phrenic nerve stimulation, and ceased with the PNS turned off. A chest X-ray obtained showed migration of the PNS lead below the superior vena cava (SVC)-right atrial junction, possibly stimulating myocardial tissue (image 1c). She was treated by reprogramming the PNS device to pace from the proximal poles of the lead still within the SVC, thereby preventing future atrial arrhythmias. This is the first reported case of PNS lead migration into the right atrium causing atrial dysrhythmias.

Transvenous phrenic nerve stimulation for the treatment of central sleep apnea reduces episodic hypoxemic burden

Study objectivesTo determine the effect of transvenous phrenic nerve stimulation (TPNS) on the composition of the nocturnal hypoxemic burden in patients with CSA. MethodsWe analysed oximetry data from baseline and follow-up overnight polysomnograms (PSG) in 134 CSA patients with implanted TPNS randomised (1:1) to neurostimulation (treatment group; TPNS on) or no stimulation (control group; TPNS off) from the remedē System Pivotal Trial. The hypoxemic burden was quantified using a battery of metrics, including the oxygen desaturation index (ODI), the relative sleep time spent below 90% SpO2 (T90) due to acute episodic desaturations (T90desat) and due to non-specific and non-cyclic drifts of SpO2 (T90non-specific). Mean change from baseline is provided. ResultsTPNS titrated to reduce respiratory events significantly reduced the ODI in the treatment group by −15.85 h−1 ± 1.99 compared to the control group, which increased 1.32 h−1 ± 1.85 (p 〈0001) and shortened the relative T90 duration by −3.81 percentage points ± 1.23 vs. 0.49 percentage points ± 1.14 increase (p = 0.012). This shortening of T90 was primarily accomplished by reducing the brief cyclic desaturations (T90desaturation: −4.32 percentage points ± 0.98 vs. 0.52 percentage points ± 0.91, p = 0.0004) while notable non-specific drifts in SpO2 remained unchanged (T90non-specific: 0.18 percentage points ± 0.62 vs. -0.13 percentage points ± 0.57, p = 0.72). ConclusionsTPNS appears to significantly reduce the nocturnal hypoxemic burden due to sleep-disordered breathing, but a considerable nocturnal hypoxemic burden from other sources remains. Further investigations are warranted to identify the best strategy to reduce the nocturnal hypoxemic burden beyond preventing respiratory events.

Design of the remedē System Therapy (rēST) study: A prospective non-randomized post-market study collecting clinical data on safety and effectiveness of the remedē system for the treatment of central sleep apnea

BackgroundCentral sleep apnea (CSA) is a disorder defined by lack of respiratory drive from the brain stem on breathing efforts. There is a lack of established therapies for CSA and most available therapies are limited by poor patient adherence, limited randomized controlled studies, and potentially adverse cardiovascular effects. The remedē System (ZOLL Respicardia, Inc., Minnetonka, Minnesota) uses transvenous phrenic nerve stimulation to stimulate the diaphragm, thereby restoring a more normal breathing pattern throughout the sleep period. MethodsThe remedē System Therapy (rēST) Study is a prospective non-randomized multicenter international study evaluating long-term safety and effectiveness of the remedē System in the post-market setting. Up to 500 adult patients with moderate to severe CSA will be enrolled and followed up to 5 years at approximately 50 sites in the United States and Europe. Safety objectives include evaluation of adverse events related to the implant procedure, device or delivered therapy, death, and hospitalizations. Effectiveness endpoints include assessment of changes in sleep-disordered breathing metrics from polysomnograms and home sleep tests, changes in daytime sleepiness using the Epworth Sleepiness Scale, and changes in QoL using the PROMIS-29 and Patient Global Assessment questionnaires. The subgroup of patients with heart failure will undergo additional assessments including echocardiography to assess cardiac reverse remodeling, 6-min walk distance, QoL assessment by Kansas City Cardiomyopathy Questionnaire and measurement of biomarkers. ConclusionThis will be the largest prospective study evaluating long-term safety and effectiveness of transvenous phrenic nerve stimulation for the treatment of moderate to severe CSA in adult patients.

Phrenic nerve stimulation for the treatment of central sleep apnea in patients with heart failure

ObjectiveCentral sleep apnea (CSA) is associated with increased morbidity and mortality in patients with heart failure (HF). We aimed to explore the effectiveness of phrenic nerve stimulation (PNS) on CSA in patients with HF.MethodsThis was a prospective and non-randomized study. The stimulation lead was inserted into the right brachiocephalic vein and attached to a proprietary neurostimulator. Monitoring was conducted during the implantation process, and all individuals underwent two-night polysomnography.ResultsA total of nine subjects with HF and CSA were enrolled in our center. There was a significant decrease in the apnea–hypopnea index (41 ± 18 vs 29 ± 25, p = 0.02) and an increase in mean arterial oxygen saturation (SaO2) (93% ± 1% vs 95% ± 2%, p = 0.03) after PNS treatment. We did not observe any significant differences of oxygen desaturation index (ODI) and SaO2 < 90% (T90) following PNS. Unilateral phrenic nerve stimulation might also categorically improve the severity of sleep apnea.ConclusionIn our non-randomized study, PNS may serve as a therapeutic approach for CSA in patients with HF.

Transvenous Phrenic Nerve Stimulation for Central Sleep Apnea

RespiCardia remedē System (Minnetonka, MN 2017), a transvenous phrenic nerve stimulator, is indicated to treat central sleep apnea (CSA) by stimulating the phrenic nerve to cause diaphragmatic contraction to restore normal breathing during sleep. CSA is associated with decreased patient quality of life and worsens cardiovascular outcomes. Systematic review was conducted according to the Preferred Reporting of Systematic Reviews and Meta-Analysis guidelines. PubMed/MEDLINE, Cochrane, EBSCO CINAHL, and Ovid databases were queried by 2 independent reviewers for English-language studies published between 2000 and 2021. The initial search screened for all occurrences of "remedē" then was further refined to include studies evaluating use of the RespiCardia remedē System as a treatment for CSA in multiple patients. A total of 124 articles were identified from the initial search results. A total of 37 articles were identified through screening of title and abstracts from initial results. Full-text review of all the articles was then completed. Of the 13 articles included, a total of 232 patients underwent device implantation. We sought to summarize the available evidence regarding patient selection for implantation, immediate and delayed complications, adherence to therapy, and polysomnographic evidence of efficacy. All 13 articles detailed significant decreases in central apnea index and many patients reported significant mild to marked improvement in quality of life. In conclusion, the remedē System has been demonstrated to improve sleep and respiratory parameters, with few complications. This device demonstrates safe and effective treatment of moderate to severe CSA in adult patients, including those with heart failure.

Effects of Adaptive Servo-Ventilation on Nocturnal Ventricular Arrhythmia in Heart Failure Patients With Reduced Ejection Fraction and Central Sleep Apnea-An Analysis From the SERVE-HF Major Substudy.

BackgroundThe SERVE-HF trial investigated the effect of treating central sleep apnoea (CSA) with adaptive servo-ventilation (ASV) in patients with heart failure with reduced ejection fraction (HFrEF).ObjectiveThe aim of the present ancillary analysis of the SERVE-HF major substudy (NCT01164592) was to assess the effects of ASV on the burden of nocturnal ventricular arrhythmias as one possible mechanism for sudden cardiac death in ASV-treated patients with HFrEF and CSA.MethodsThree hundred twelve patients were randomized in the SERVE-HF major substudy [no treatment of CSA (control) vs. ASV]. Polysomnography including nocturnal ECG fulfilling technical requirements was performed at baseline, and at 3 and 12 months. Premature ventricular complexes (events/h of total recording time) and non-sustained ventricular tachycardia were assessed. Linear mixed models and generalized linear mixed models were used to analyse differences between the control and ASV groups, and changes over time.ResultsFrom baseline to 3- and 12-month follow-up, respectively, the number of premature ventricular complexes (control: median 19.7, 19.0 and 19.0; ASV: 29.1, 29.0 and 26.0 events/h; p = 0.800) and the occurrence of ≥1 non-sustained ventricular tachycardia/night (control: 18, 25, and 18% of patients; ASV: 24, 16, and 24% of patients; p = 0.095) were similar in the control and ASV groups.ConclusionAddition of ASV to guideline-based medical management had no significant effect on nocturnal ventricular ectopy or tachyarrhythmia over a period of 12 months in alive patients with HFrEF and CSA. Findings do not further support the hypothesis that ASV may lead to sudden cardiac death by triggering ventricular tachyarrhythmia.

0828 Positional Central Sleep Apnea

Abstract Introduction Obstructive sleep apnea (OSA) is well known to often improve with non-supine positioning as opposed to supine positioning. The prevalence of OSA that may improve on proper positioning is 50-60% and the prevalence of OSA that appears when supine and disappears when non-supine is 25-30%. Sleeping in a lateral positioning is thought to reduce pressure on the airway, shift the directional effect of gravity on airway structures, and counteract physiologic genioglossus collapse that occurs when supine. On the other hand, the effect of positional changes on the severity of central sleep apnea (CSA) is not well documented aside from Cheyne-stokes breathing in congestive heart failure. Report of Cases: We present two cases of positional CSA. One patient is a 52-year-old male with a history of traumatic brain injury, hypogonadism, hypothyroidism and Parkinson’s Disease. He underwent split-polysomnography (PSG) for dream enactment behavior, was found to have severe CSA, which occurred almost exclusively supine (Supine Apnea-Hypopnea Index (AHI) 66/hr, Non-Supine 0.8/hr). A positional belt was recommended to the patient. The second patient is an 89-year-old male with history of chronic obstructive pulmonary disease and chronic kidney disease who underwent PSG for symptoms of sleep apnea. He was found to have severe obstructive and central sleep apnea with periods of Cheyne-stokes breathing. This also occurred almost exclusively supine (Supine AHI 69/hr, Non-Supine 0/hr) and improved on continuous positive airway pressure (CPAP) independent of position (AHI 6/hr). CPAP or positional belt was recommended to the patient. Conclusion Positional CSA unrelated to congestive heart failure is an uncommon phenomenon with poorly understood pathophysiology. Treatment of CSA is often challenging and based on elucidating and addressing the underlying cause such as optimizing treatment of heart failure. Positional therapy is characteristically thought of as a potential treatment option for OSA. However, our findings further support the presence of a phenotype of central sleep apnea that may respond to positional therapy. Support (If Any)

0819 Restless Sleep, Snoring, Excessive Daytime Sleepiness, And Ataxia: A Pediatric Quandary

Abstract Introduction Central sleep apnea in pediatrics is inherently complex, often going undiagnosed and untreated. Signs and symptoms of central nervous system dysfunction may be attributed to more common childhood conditions. We aim to educate on the diagnosis and treatment of central sleep apnea in this vulnerable patient population. Report of Cases: A 12-year-old girl presents for initial sleep visit with global developmental delay, borderline obesity, chronic headaches, early morning tremors, and insulin resistance. She has history of snoring and restless sleep for years with severe daytime sleepiness for the past three months with worsening over two to four weeks. She is unable to stay awake in school. Epworth sleepiness scale (ESS) score is twenty-one. There is history of recurrent Strep but no history of infectious mononucleosis or influenza infection. Primary sleep disorders or CNS hypersomnia are suspected, and polysomnogram with MSLT is ordered. MRI of the brain is pending. The patient presents to the emergency department ten days later with frontal headaches, ataxia, altered speech, and oral aversion. CT head is normal. Hematology, neurology, and neurosurgery are consulted. MRI of the brain shows thrombosis of the superior sagittal sinus, the right transverse sinus, the right sigmoid sinus, the right jugular bulb, as well as cortical veins overlying both cerebral hemispheres, and she is started on anticoagulation for suspected stroke. A polysomnogram shows a severe degree of central sleep apnea with a central apnea index of 49.9 events per hour. There is significant periodic breathing present. There is no nonapneic hypoxemia or sleep hypoventilation present, and the patient is scheduled for an oxygen titration study. Conclusion Central sleep apnea is more prevalent in older male individuals and may affect patients with heart failure1.Pediatricians and subspecialists must remain vigilant as children are also susceptible to medical conditions which result in central nervous system dysfunction. Support (If Any) 1.) Donovan LM, Kapur VK. Prevalence and Characteristics of Central Compared to Obstructive Sleep Apnea: Analyses from the Sleep Heart Health Study Cohort. Sleep. 2016;39(7):1353-1359. Published 2016 Jul 1.doi:10.5665/sleep.5962

Diagnostic and therapeutic approach of central sleep apnea in heart failure – the role of adaptive servo-ventilation. A statement of the Portuguese society of pulmonology and the Portuguese sleep association

It is known that patients with heart failure (HF) have an increased risk of developing central sleep apnoea (CSA), with Cheyne-Stokes respiration. The development of servo-ventilation aimed to treat CSA and improve the quality of life (QoL) of these patients. A large randomized clinical study, SERVE-HF, was conducted in order to test this theory in patients with HF and reduced ejection fraction (HFrEF). The results from this trial seemed to indicate that, in these patients, there was no beneficial effect of the assisted ventilation in CSA treatment. More surprisingly, an increased rate of all-cause or cardiovascular mortality was observed. This has led to dramatic changes in clinical practice, with decreased frequency of servo-ventilation prescription across Europe, including Portugal, due to changes in the guidelines. However, SERVE-HF was conducted only in severe systolic HF patients with CSA, and caution must be taken when extrapolating these results to HF patients with preserved ejection fraction or CSA patients without HF.The study also showed poor adherence, methodological and statistical gaps, including study design, patient selection, data collection and analysis, treatment adherence, and group crossovers, which have not been discussed in the trial as potential confounding factors and raise several concerns. Moreover, the adaptive servo-ventilation (ASV) device used in SERVE-HF was unable to lower the minimum support pressure below 3 mm H20, and this has been suggested as one of the probable contributing reasons to the excess mortality observed in this study. This limitation has since been solved, and this ASV device is no longer used.This paper describes the results of a Portuguese Task Force on the treatment of central sleep apnoea in patients with chronic HF.

Management of Obstructive Sleep Apnea in Patients With Heart Failure.

Sleep apnea is traditionally classified as obstructive sleep apnea (OSA), which occurs when the upper airway collapses due to the relaxation of oropharyngeal musculature, and central sleep apnea occurs when the brainstem cannot stimulate breathing. Most sleep apnea in patients with heart failure (HF) results from coexisting OSA and central sleep apnea (CSA), or complex sleep apnea syndrome. OSA and CSA are common in HF and can be involved in its progression by exposure to the heart to intermittent hypoxia, increased preload and afterload, activating sympathetic, and decreased vascular endothelial function. A majority of treatments have been investigated in patients with CSA and HF; however, less or short-term randomized trials demonstrated whether treating OSA in patients with HF could improve morbidity and mortality. OSA could directly influence the patient's recovery. This review will focus on past and present studies on the various therapies for OSA in patients with HF and summarize CSA treatment options for reasons of reference and completeness. More specifically, the treatment covered include surgical and non-surgical treatments and reported the positive and negative consequences for these treatment options, highlighting possible implications for clinical practice and future research directions.

Sleep-related breathing disorders in patients with heart failure: current aspects of treatment. Part II

The second part of the review highlights treatments for different types of sleep apnea in patients with heart failure. In both obstructive and central sleep apnea, ventilatory support during sleep takes a special place in treatment. Therefore, the review details the role of different ventilation modes (in particular, CPAP therapy and adaptive servo-ventilation), analyzes available evidence-based medicine data. The role of low-flow oxygen therapy, surgical treatment, implantable devices, specific therapy (theophylline, acetazolamide) in the treatment of central sleep apnea is also shown, and a novel method of treating central sleep apnea is considered — phrenic nerve stimulation.

Central sleep apnea treatment in patients with heart failure with reduced ejection fraction: a network meta-analysis.

Adaptive servo-ventilation (ASV) is contraindicated for the treatment of central sleep apnea (CSA) in patients with heart failure with reduced ejection fraction (HFrEF), limiting treatment options. Though continuous positive airway pressure (CPAP), bi-level PAP with back-up rate (BPAP-BUR), and transvenous phrenic nerve stimulation (TPNS) are alternatives, not much is known about their comparative efficacies, which formed the basis of conducting this network meta-analysis. We sought to analyze their comparative effectiveness in reducing apnea hypopnea index (AHI). Additionally, we also studied their comparative effectiveness on subjective daytime sleepiness as assessed by Epworth sleepiness score (ESS). Randomized controlled trials (RCTs) from PubMed were analyzed in a network meta-analysis and relative superiority was computed based on P-score ranking and Hasse diagrams. Network meta-analysis based on 8 RCTs showed that when compared to guideline-directed medical therapy (GDMT-used as a common comparator across trials), reduction in AHI by ASV (- 26.05 [- 38.80; - 13.31]), TPNS (- 24.90 [- 42.88; - 6.92]), BPAP-BUR (- 20.36 [- 36.47; - 4.25]), and CPAP (- 16.01 [- 25.42; - 6.60]) were statistically significant but not between the interventions. Based on 6 RCTs of all the interventions, only TPNS showed a statistically significant decrease in ESS (- 3.70 (- 5.58; - 1.82)) when compared to GDMT, while also showing significant differences when compared with ASV (- 3.20 (- 5.86; - 0.54)), BPAP-BUR (- 4.00 (- 7.33; - 0.68)), and CPAP (- 4.45 (- 7.75; - 1.14)). Ranking of treatments based on Hasse diagram, accounting for both AHI and ESS as outcomes for relative hierarchy showed relative superiority of both ASV and TPNS over BPAP-BUR and CPAP. Results indicated relative superiority of TPNS and ASV to BPAP-BUR and CPAP in their effects on AHI and ESS.