Effects of auto-servo ventilation on patients with sleep-disordered breathing, stable systolic heart failure and concomitant diastolic dysfunction: subanalysis of a randomized controlled trial

The efficacy and safety of adaptive servo-ventilation therapy for heart failure with preserved ejection fraction

It is unclear whether adaptive servo-ventilation (ASV) therapy for heart failure with preserved ejection fraction (HFpEF) is effective. The aim of this study was to investigate the details of ASV use, and to evaluate the effectiveness and safety of ASV in real-world HFpEF patients. We retrospectively enrolled 36 HFpEF patients at nine cardiovascular centers who initiated ASV therapy during hospitalization or on outpatient basis and were able to continue using it at home from 2012 to 2017 and survived for at least one year thereafter. The number of hospitalizations for heart failure (HF) during the 12 months before and 12 months after introduction of ASV at home was compared. The median number of HF hospitalizations for each patient was significantly reduced from 1 [interquartile range: 1-2] in the 12 months before introduction of ASV to 0 [0-0] in the 12 months after introduction of ASV (p < 0.001). In subgroup analysis, reduction in heart failure hospitalization was significantly greater in female patients, patients with a body mass index < 25, and those with moderate or severe tricuspid valve regurgitation. In patients with HFpEF, the number of HF hospitalizations was significantly decreased after the introduction of ASV. HFpEF patients with female sex, BMI < 25, or moderate to severe tricuspid valve regurgitation are potential candidates who might benefit from ASV therapy.

Non-invasive positive pressure ventilation for central sleep apnoea in adults

BACKGROUND

Central sleep apnoea (CSA) is characterised by abnormal patterns of ventilation during sleep due to a dysfunctional drive to breathe. Consequently, people with CSA may present poor sleep quality, sleep fragmentation, inattention, fatigue, daytime sleepiness, and reduced quality of life.

OBJECTIVES

To assess the effectiveness and safety of non-invasive positive pressure ventilation (NIPV) for the treatment of adults with CSA.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and Scopus on 6 September 2021. We applied no restrictions on language of publication. We also searched clinical trials registries for ongoing and unpublished studies, and scanned the reference lists of included studies to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) reported in full text, those published as abstract only, and unpublished data.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, extracted data, and assessed risk of bias of the included studies using the Cochrane risk of bias tool version 1.0, and the certainty of the evidence using the GRADE approach. In the case of disagreement, a third review author was consulted.

MAIN RESULTS

We included 15 RCTs with a total of 1936 participants, ranging from 10 to 1325 participants. All studies had important methodological limitations. We assessed most studies (11 studies) as at high risk of bias for at least one domain, and all studies as at unclear risk of bias for at least two domains. The trials included participants aged > 18 years old, of which 70% to 100% were men, who were followed from one week to 60 months. The included studies assessed the effects of different modes of NIPV and CSA. Most participants had CSA associated with chronic heart failure. Because CSA encompasses a variety of causes and underlying clinical conditions, data were carefully analysed, and different conditions and populations were not pooled. The findings for the primary outcomes for the seven evaluated comparisons are presented below.  Continuous positive airway pressure (CPAP) plus best supportive care versus best supportive care in CSA associated with chronic heart failure In the short term, CPAP plus best supportive care may reduce central apnoea hypopnoea index (AHI) (mean difference (MD) -14.60, 95% confidence interval (CI) -20.11 to -9.09; 1 study; 205 participants). However, CPAP plus best supportive care may result in little to no difference in cardiovascular mortality compared to best supportive care alone. The evidence for the effect of CPAP plus best supportive care on all-cause mortality is very uncertain. No adverse effects were observed with CPAP, and the results for adverse events in the best supportive care group were not reported. Adaptive servo ventilation (ASV) versus CPAP in CSA associated with chronic heart failure The evidence is very uncertain about the effect of ASV versus CPAP on quality of life evaluated in both the short and medium term. Data on adverse events were not reported, and it is not clear whether data were sought but not found. ASV versus bilevel ventilation in CSA associated with chronic heart failure In the short term, ASV may result in little to no difference in central AHI. No adverse events were detected with ASV, and the results for adverse events in the bilevel ventilation group were not reported. ASV plus best supportive care versus best supportive care in CSA associated with chronic heart failure In the medium term, ASV plus best supportive care may reduce AHI compared to best supportive care alone (MD -20.30, 95% CI -28.75 to -11.85; 1 study; 30 participants). In the long term, ASV plus best supportive care likely increases cardiovascular mortality compared to best supportive care (risk ratio (RR) 1.25, 95% CI 1.04, 1.49; 1 study; 1325 participants). The evidence suggests that ASV plus best supportive care may result in little to no difference in quality of life in the short, medium, and long term, and in all-cause mortality in the medium and long term. Data on adverse events were evaluated but not reported. ASV plus best supportive care versus best supportive care in CSA with acute heart failure with preserved ejection fraction Only adverse events were reported for this comparison, and no adverse events were recorded in either group. ASV versus CPAP maintenance in CPAP-induced CSA In the short term, ASV may slightly reduce central AHI (MD -4.10, 95% CI -6.67 to -1.53; 1 study; 60 participants), but may result in little to no difference in quality of life. Data on adverse events were not reported, and it is not clear whether data were sought but not found. ASV versus bilevel ventilation in CPAP-induced CSA In the short term, ASV may slightly reduce central AHI (MD -8.70, 95% CI -11.42 to -5.98; 1 study; 30 participants) compared to bilevel ventilation. Data on adverse events were not reported, and it is not clear whether data were sought but not found.

AUTHORS' CONCLUSIONS

CPAP plus best supportive care may reduce central AHI in people with CSA associated with chronic heart failure compared to best supportive care alone. Although ASV plus best supportive care may reduce AHI in people with CSA associated with chronic heart failure, it likely increases cardiovascular mortality in these individuals. In people with CPAP-induced CSA, ASV may slightly reduce central AHI compared to bilevel ventilation and to CPAP. In the absence of data showing a favourable impact on meaningful patient-centred outcomes and defining clinically important differences in outcomes in CSA patients, these findings need to be interpreted with caution. Considering the level of certainty of the available evidence and the heterogeneity of participants with CSA, we could draw no definitive conclusions, and further high-quality trials focusing on patient-centred outcomes, such as quality of life, quality of sleep, and longer-term survival, are needed to determine whether one mode of NIPV is better than another or than best supportive care for any particular CSA patient group.

Treatment of Sleep Apnea with Positive Airway Pressure and Its Association with Diastolic Dysfunction: A Systematic Review and Meta-Analysis

BACKGROUND

This meta-analysis assessed the effect of long-term (>6 weeks) noninvasive positive airway pressure (PAP) on diastolic function in patients with obstructive sleep apnea (OSA).

METHODS

We searched the databases for randomized clinical trials including Ovid MEDLINE, Ovid Embase Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 20, 2019. The search was not restricted to time, publication status, or language. Two independent investigators screened the studies and extracted the data, in duplicate. Risk of bias was assessed using Cochrane collaboration tools.

RESULTS

A total of 2,753 abstracts were resulted from literature search. A total of 9 randomized clinical trials assessing the effect of long-term (>6 weeks) PAP on diastolic function in patients with OSA including 833 participants were included. The following echo parameters were found in treated patients: a decrease in deceleration time (-39.49 ms CI [-57.24, -21.74]; p = 0.000), isovolumic relaxation time (-9.32 ms CI [-17.08, -1.57]; p = 0.02), and the ratio of early mitral inflow velocity to mitral annular early diastolic velocity (-1.38 CI [-2.6, -0.16]; p = 0.03). However, changes in left-atrial volume index and the ratio of early to late mitral inflow velocities were not statistically different. The risk of bias was mild to moderate among the studies.

CONCLUSION

Our results suggest that chronic treatment of moderate to severe OSA with noninvasive PAP is associated with improvement in echocardiographic findings of diastolic dysfunction.

Positive airway pressure therapy for the treatment of central sleep apnoea associated with heart failure

BACKGROUND

Ischaemic heart disease including heart failure is the most common cause of death in the world, and the incidence of the condition is rapidly increasing. Heart failure is characterised by symptoms such as fatigue and breathlessness during light activity, as well as disordered breathing during sleep. In particular, sleep disordered breathing (SDB), including central sleep apnoea (CSA) and obstructive sleep apnoea (OSA), is highly prevalent in people with chronic heart failure. A previous meta-analysis demonstrated that positive airway pressure (PAP) therapy dramatically increased the survival rate of people with heart failure who had CSA, and thus could contribute to improving the prognosis of these individuals. However, recent trials found that adaptive servo-ventilation (ASV) including PAP therapy had a higher risk of all-cause mortality and cardiovascular mortality. A meta-analysis that included recent trials was therefore needed.

OBJECTIVES

To assess the effects of positive airway pressure therapy for people with heart failure who experience central sleep apnoea.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, and Web of Science Core Collection on 7 February 2019 with no limitations on date, language, or publication status. We also searched two clinical trials registers in July 2019 and checked the reference lists of primary studies.

SELECTION CRITERIA

We excluded cross-over trials and included individually randomised controlled trials, reported as full-texts, those published as abstract only, and unpublished data.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted outcome data from the included studies. We double-checked that data had been entered correctly by comparing the data presented in the systematic review with study reports. We analysed dichotomous data as risk ratios (RRs) with 95% confidence intervals (CIs) and continuous data as mean difference (MD) or standardised mean difference (SMD) with 95% CIs. Furthermore, we performed subgroup analysis in the ASV group or continuous PAP group separately. We used GRADEpro GDT software to assess the quality of evidence as it relates to those studies that contribute data to the meta-analyses for the prespecified outcomes.

MAIN RESULTS

We included 16 randomised controlled trials involving a total of 2125 participants. The trials evaluated PAP therapy consisting of ASV or continuous PAP therapy for 1 to 31 months. Many trials included participants with heart failure with reduced ejection fraction. Only one trial included participants with heart failure with preserved ejection fraction. We are uncertain about the effects of PAP therapy on all-cause mortality (RR 0.81, 95% CI 0.54 to 1.21; participants = 1804; studies = 6; I² = 47%; very low-quality evidence). We found moderate-quality evidence of no difference between PAP therapy and usual care on cardiac-related mortality (RR 0.97, 95% CI 0.77 to 1.24; participants = 1775; studies = 5; I² = 11%). We found low-quality evidence of no difference between PAP therapy and usual care on all-cause rehospitalisation (RR 0.95, 95% CI 0.70 to 1.30; participants = 1533; studies = 5; I² = 40%) and cardiac-related rehospitalisation (RR 0.97, 95% CI 0.70 to 1.35; participants = 1533; studies = 5; I² = 40%). In contrast, PAP therapy showed some indication of an improvement in quality of life scores assessed by all measurements (SMD -0.32, 95% CI -0.67 to 0.04; participants = 1617; studies = 6; I² = 76%; low-quality evidence) and by the Minnesota Living with Heart Failure Questionnaire (MD -0.51, 95% CI -0.78 to -0.24; participants = 1458; studies = 4; I² = 0%; low-quality evidence) compared with usual care. Death due to pneumonia (N = 1, 3% of PAP group); cardiac arrest (N = 18, 3% of PAP group); heart transplantation (N = 8, 1% of PAP group); cardiac worsening (N = 3, 9% of PAP group); deep vein thrombosis/pulmonary embolism (N = 1, 3% of PAP group); and foot ulcer (N = 1, 3% of PAP group) occurred in the PAP therapy group, whereas cardiac arrest (N = 16, 2% of usual care group); heart transplantation (N = 12, 2% of usual care group); cardiac worsening (N = 5, 14% of usual care group); and duodenal ulcer (N = 1, 3% of usual care group) occurred in the usual care group across three trials.

AUTHORS' CONCLUSIONS

The effect of PAP therapy on all-cause mortality was uncertain. In addition, although we found evidence that PAP therapy did not reduce the risk of cardiac-related mortality and rehospitalisation, there was some indication of an improvement in quality of life for heart failure patients with CSA. Furthermore, the evidence was insufficient to determine whether adverse events were more common with PAP than with usual care. These findings were limited by low- or very low-quality evidence. PAP therapy may be worth considering for individuals with heart failure to improve quality of life.

Use of adaptive servo ventilation therapy as treatment of sleep-disordered breathing and heart failure: a systematic review and meta-analysis

PURPOSE

Adaptive servoventilation (ASV) has been reported to show improvement in patients with sleep-disordered breathing (SDB) and heart failure (HF); however, its role as a second-line or adjunctive treatment is not clear. We conducted a systematic review and meta-analysis of new existing data including cardiac mechanistic factor, geometry, and cardiac biomarkers.

METHODS

We systematically searched for randomized controlled trials (RCTs) and cohort studies that assessed the efficacy or effectiveness of ASV compared to conventional treatments for SDB and HF in five research databases from their inception to November 2018. Random-effects meta-analyses using the inverse variance method and stratified by study design were performed.

RESULTS

We included 15 RCTs (n = 859) and 5 cohorts (n = 162) that met our inclusion criteria. ASV significantly improved left ventricular ejection fraction (LVEF) in cohorts (MD 6.96%, 95% CI 2.58, 11.34, p = 0.002), but not in RCTs. Also, the ASV group had significantly lower apnea-hypopnea index (AHI) in both cohorts (MD - 26.02, 95% CI - 36.94, - 15.10, p < 0.00001) and RCTs (MD - 21.83, 95% CI - 28.17, - 15.49, p < 0.00001). ASV did not significantly decrease the E/e' ratio in RCTs or in cohorts. Finally, ASV significantly decreased brain natriuretic peptide (BNP) in the cohorts (SMD - 121.99, CI 95% - 186.47, - 57.51, p = 0.0002) but not in RCTs. ASV did not have a significant effect on systolic blood pressure, diastolic blood pressure, and cardiac diameters.

CONCLUSIONS

ASV therapy is associated with improvements of AHI in comparison to alternative treatments in patients with SDB and HF. ASV did not improve LVEF or E/e' ratios in randomized trials; other intermediate outcomes did not improve significantly.

Noninvasive ventilation improves cardiac function in patients with chronic heart failure

Chronic heart failure (CHF) has been shown to be associated with an increased incidence of sleep-disordered breathing. Whether treatment with noninvasivepositive-pressure ventilation (NPPV), including continuous positive airway pressure, bi-level positive airway pressure and adaptive servo-ventilation, improves clinical outcomes of CHF patients is still debated. 2,832 CHF patients were enrolled in our analysis. NPPV was significantly associated with improvement in left ventricular ejection fraction (39.39% vs. 34.24%; WMD, 5.06; 95% CI, 3.30-6.81; P < 0.00001) and plasma brain natriuretic peptide level (268.23 pg/ml vs. 455.55 pg/ml; WMD, −105.66; 95% CI, [−169.19]-[−42.13]; P = 0.001). However, NPPV did not reduce all-cause mortality (0.26% vs. 0.24%; OR, 1.13; 95% CI, 0.93-1.37; P = 0.22) or re-hospitalization rate (57.86% vs. 59.38%; OR, 0.47; 95% CI, 0.19-1.19; P = 0.02) as compared with conventional therapy. Despite no benefits on hard endpoints, NPPV may improve cardiac function of CHF patients. These data highlight the important role of NPPV in the therapy of CHF.

Epidemiology of Sleep-Disordered Breathing and Heart Failure: What Drives What

PURPOSE OF REVIEW

The bidirectional relationships that have been demonstrated between heart failure (HF) and central sleep apnea (CSA) demand further exploration with respect to the implications that each condition has for the other. This review discusses the body of literature that has accumulated on these relationships and how CSA and its potential treatment may affect outcomes in patients with CSA.

RECENT FINDINGS

Obstructive sleep apnea (OSA) can exacerbate hypertension, type 2 diabetes, obesity, and atherosclerosis, which are known predicates of HF. Conversely, patients with HF more frequently exhibit OSA partly due to respiratory control system instability. These same mechanisms are responsible for the frequent association of HF with CSA with or without a Hunter-Cheyne-Stokes breathing (HCSB) pattern. Just as is the case with OSA, patients with HF complicated by CSA exhibit more severe cardiac dysfunction leading to increased mortality; the increase in severity of HF can in turn worsen the degree of sleep disordered breathing (SDB). Thus, a bidirectional relationship exists between HF and both phenotypes of SDB; moreover, an individual patient may exhibit a combination of these phenotypes. Both types of SDB remain significantly underdiagnosed in patients with HF and hence undertreated. Appropriate screening for, and treatment of, OSA is clearly a significant factor in the comprehensive management of HF, while the relevance of CSA remains controversial. Given the unexpected results of the Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients with Heart Failure trial, it is now of paramount importance that additional analysis of these data be expeditiously reported. It is also critical that ongoing and proposed prospective studies of this issue proceed without delay.

Adaptive servo ventilation for central sleep apnoea in heart failure: SERVE-HF on-treatment analysis

This on-treatment analysis was conducted to facilitate understanding of mechanisms underlying the increased risk of all-cause and cardiovascular mortality in heart failure patients with reduced ejection fraction and predominant central sleep apnoea randomised to adaptive servo ventilation versus the control group in the SERVE-HF trial.Time-dependent on-treatment analyses were conducted (unadjusted and adjusted for predictive covariates). A comprehensive, time-dependent model was developed to correct for asymmetric selection effects (to minimise bias).The comprehensive model showed increased cardiovascular death hazard ratios during adaptive servo ventilation usage periods, slightly lower than those in the SERVE-HF intention-to-treat analysis. Self-selection bias was evident. Patients randomised to adaptive servo ventilation who crossed over to the control group were at higher risk of cardiovascular death than controls, while control patients with crossover to adaptive servo ventilation showed a trend towards lower risk of cardiovascular death than patients randomised to adaptive servo ventilation. Cardiovascular risk did not increase as nightly adaptive servo ventilation usage increased.On-treatment analysis showed similar results to the SERVE-HF intention-to-treat analysis, with an increased risk of cardiovascular death in heart failure with reduced ejection fraction patients with predominant central sleep apnoea treated with adaptive servo ventilation. Bias is inevitable and needs to be taken into account in any kind of on-treatment analysis in positive airway pressure studies.

Definition, discrimination, diagnosis and treatment of central breathing disturbances during sleep

The complexity of central breathing disturbances during sleep has become increasingly obvious. They present as central sleep apnoeas (CSAs) and hypopnoeas, periodic breathing with apnoeas, or irregular breathing in patients with cardiovascular, other internal or neurological disorders, and can emerge under positive airway pressure treatment or opioid use, or at high altitude. As yet, there is insufficient knowledge on the clinical features, pathophysiological background and consecutive algorithms for stepped-care treatment. Most recently, it has been discussed intensively if CSA in heart failure is a “marker” of disease severity or a “mediator” of disease progression, and if and which type of positive airway pressure therapy is indicated. In addition, disturbances of respiratory drive or the translation of central impulses may result in hypoventilation, associated with cerebral or neuromuscular diseases, or severe diseases of lung or thorax. These statements report the results of an European Respiratory Society Task Force addressing actual diagnostic and therapeutic standards. The statements are based on a systematic review of the literature and a systematic two-step decision process. Although the Task Force does not make recommendations, it describes its current practice of treatment of CSA in heart failure and hypoventilation.

Adaptive servoventilation improves cardiac dysfunction and prognosis in heart failure patients with sleep-disordered breathing: a meta-analysis

BACKGROUND

Adaptive servoventilation (ASV) is a new therapeutic modality to treat sleep-disordered breathing (SDB) especially for central sleep apnoea associated with Cheyne-Stokes respiration, whereas the role of ASV in SDB patients with heart failure (HF) is controversial. The purpose of this study was to evaluate the effects of ASV on these patients through a meta-analysis of published data.

METHODS

A comprehensive literature search was performed to identify studies focused on ASV through databases, including PubMed, Medline, Embase, Cochrane Library and Web of science from 1950 to 2014. Parallel randomised controlled trials which compared ASV to other controls in HF and SDB patients with extractable data were meet our inclusion criteria. Random effects meta-analysis models were applied using RevMan 5.2.

RESULTS

Seven studies involving 301 patients were recruited in the meta-analysis. The weighted mean difference in apnoea hyponea index (-17.73 events/h, 95% CI, -21.85 to -2.94) and left ventricular ejection fraction (MD: 4.68, 95% CI, 2.74-6.63) both favored ASV compared to control conditions. The urinary noradrenaline level (MD: -32.18, 95%CI: -44.07 to -20.09) was decreased, while the exercise capacity measured by 6-min walk distance (MD: 41.26, 95% CI, 17.06-65.45) was improved after ASV treatment. Whereas neither left ventricular end-diastolic diameter (LVEDD) nor Epworth sleepiness-scale score (ESS) significantly changed after ASV therapy.

CONCLUSIONS

ASV is superior to other therapy, as it can result in good consequences for patients with SDB and improve their prognosis in cardiac function. Further studies will still be needed to assess the benefit of it.

New developments in the use of positive airway pressure for obstructive sleep apnea

Obstructive sleep apnea (OSA) is a disorder which afflicts a large number of individuals around the world. OSA causes sleepiness and is a major cardiovascular risk factor. Since its inception in the early 1980's, continuous positive airway pressure (CPAP) has emerged as the major treatment of OSA, and it has been shown to improve sleepiness, hypertension, and a number of cardiovascular indices. Despite its successes, adherence with treatment remains a major limitation. Herein we will review the evidence behind the use of positive airway pressure (PAP) therapy, its various modes, and the methods employed to improve adherence. We will also discuss the future of PAP therapy in OSA and personalization of care.

Effectiveness of adaptive servo-ventilation

Adaptive servo-ventilation (ASV) has been developed as a specific treatment for sleep-disordered breathing, in particular Cheyne-Stokes respiration with central sleep apnea (CSA). Heart failure patients often have sleep-disordered breathing, which consists of either obstructive sleep apnea (OSA) or CSA. Other medical conditions, such as stroke, acromegaly, renal failure, and opioid use may be associated with CSA. Continuous positive airway pressure (CPAP) therapy is widely used for patients with OSA, but some of these patients develop CSA on CPAP, which is called treatment-emergent CSA. CPAP can be useful as a treatment for these various forms of CSA, but it is insufficient to eliminate respiratory events in approximately half of patients with CSA. As compared to CPAP, ASV may be a better option to treat CSA, with sufficient alleviation of respiratory events as well as improvement of cardiac function in heart failure patients. In patients without heart failure, ASV can also alleviate CSA and relieve their symptom. Recently, ASV has been widely used for patients with various forms of CSA. ASV may be also used in the setting without CSA, but it should be assessed more carefully. Clinicians should have a better understanding of the indications for ASV in each setting.

Sleep-disordered Breathing in Heart Failure - Current State of the Art

Sleep-disordered breathing (SDB), either obstructive sleep apnoea (OSA) or central sleep apnoea (CSA)/Cheyne-Stokes respiration (CSR) and often a combination of the two, is highly prevalent in patients with heart failure (HF), is associated with reduced functional capacity and quality of life, and has a negative prognostic impact. European HF guidelines identify that sleep apnoea is of concern in patients with HF. Continuous positive airway pressure is the treatment of choice for OSA, and adaptive servoventilation (ASV) appears to be the most consistently effective therapy for CSA/CSR while also being able to treat concomitant obstructive events. There is a growing body of evidence that treating SDB in patients with HF, particularly using ASV for CSA/CSR, improves functional outcomes such as HF symptoms, cardiac function, cardiac disease markers, exercise tolerance and quality of life. However, conflicting results have been reported on 'hard' outcomes such as mortality and healthcare utilisation, and the influence of effectively treating SDB, including CSA/CSR, remains to be determined in randomised clinical trials. Two such trials (SERVE-HF and ADVENT-HF) in chronic stable HF and another in post-acute decompensated HF (CAT-HF) are currently underway.