Efficacy of adaptive servoventilation in patients with congestive heart failure and Cheyne-Stokes respiration:

Auto-trilevel versus bilevel positive airway pressure ventilation for hypercapnic overlap syndrome patients

PURPOSE

Although bilevel positive airway pressure (Bilevel PAP) therapy is usually used for overlap syndrome (OS), there is still a portion of OS patients in whom Bilevel PAP therapy could not simultaneously eliminate residual apnea events and hypercapnia. The current study was expected to explore whether auto-trilevel positive airway pressure (auto-trilevel PAP) therapy with auto-adjusting end expiratory positive airway pressure (EEPAP) can serve as a better alternative for these patients.

METHODS

From January of 2014 to June of 2016, 32 hypercapnic OS patients with stable chronic obstructive pulmonary diseases (COPD) and moderate-to-severe obstructive sleep apnea syndrome (OSAS) were recruited. Three variable modes of positive airway pressure (PAP) from the ventilator (Prisma25ST, Weinmann Inc., Germany) were applicated for 8 h per night. We performed the design of each mode at each night with an interval of two nights with no PAP treatment as a washout period among different modes. In Bilevel-1 mode (Bilevel-1), the expiratory positive airway pressure (EPAP) delivered from Bilevel PAP was always set as the lowest PAP for abolishment of snoring. For each patient, the inspiratory positive airway pressure (IPAP) was constantly set the same as the minimal pressure for keeping end-tidal CO₂ (ETCO₂) ≤45 mmHg for all three modes. However, the EPAP issued by Bilevel PAP in Bilevel-2 mode (Bilevel-2) was kept 3 cmH₂O higher than that in Bilevel-1. In auto-trilevel mode (auto-trilevel) with auto-trilevel PAP, the initial part of EPAP was fixed at the same PAP as that in Bilevel-1 while the EEPAP was automatically regulated to rise at a range of ≤4 cmH₂O based on nasal airflow wave changes. Comparisons were made for parameters before and during or following treatment as well as among different PAP therapy modes. The following parameters were compared such as nocturnal apnea hypopnea index (AHI), minimal SpO₂ (minSpO₂), arousal index, sleep structure and efficiency, morning PaCO₂, and daytime Epworth Sleepiness Scale (ESS).

RESULTS

Compared with the parameters before PAP therapies, during each mode of PAP treatment, significant reduction was detected in nocturnal AHI, arousal index, morning PaCO₂, and daytime ESS while significant elevation was revealed in nocturnal minSpO₂ and sleep efficiency (all P < 0.01). Comparison among three PAP modes indicated that under the same IPAP, the auto-trilevel PAP mode could result in the lowest arousal index, daytime ESS, and the highest sleep efficiency. Compared with Bilevel-1, it was detected that (a) AHI was lower but minSpO₂ was higher in both Bilevel-2 and auto-trilevel (all P < 0.05) and (b) morning PaCO₂ showed no statistical difference from that in auto-trilevel but displayed higher in Bilevel-2 (P < 0.05). Compared with Bilevel-2, in auto-trilevel, both AHI and minSpO₂ showed no obvious changes (all P > 0.05) except with a lower morning PaCO₂ (P < 0.05).

CONCLUSION

Auto-trilevel PAP therapy was superior over conventional Bilevel PAP therapy for hypercapnic OS patients with their OSAS moderate to severe, since auto-trilevel PAP was more efficacious in synchronous elimination of residual obstructive apnea events and CO₂ retention as well as in obtaining a better sleep quality and milder daytime drowsiness.

Patients with Cheyne-Stokes respiration and heart failure: patient tolerance after three-month discontinuation of treatment with adaptive servo-ventilation

The recent SERVE HF study concluded that patients with chronic heart failure (CHF) and Cheyne-Stokes respiration (CSR) have increased mortality when treated with adaptive servo-ventilation (ASV). We, therefore, wanted to explore if these patients tolerated discontinuation of ASV treatment. The study was a prospective post-ASV treatment observational design with a 3-month follow-up period. 14 patients from our outpatient clinic, all male, were originally diagnosed with CHF and Cheyne-Stokes respiration, which is a clinical form of central sleep apnea. Left ventricular ejection fraction (LVEF) was ≤45% when ASV treatment was initiated. Median machine use was 68 (42-78) months when the patients were instructed to terminate ASV treatment. The patients were then followed during conventional CHF treatment for 3 months. Study baseline was set the last ASV treatment day. Sleep data were collected from the machine the last day of use. Apnea-hypopnea index (AHI), LVEF, 6-min walk test and 24-h ambulatory electrocardiogram recordings were performed at baseline and at study end. Life quality data were obtained using The Minnesota Living with Heart Failure Questionaire (MLHFQ). New York Heart Association Functional Classification (NYHA) was registered. An ambulatory sleep screening was performed at study end. AHI increased significantly after 3 months without ASV treatment [from 1.6 (0.8-3.2) to 39.2 (24.3-44.1, p = 0.001)]. Quality of life (QOL) decreased significantly: 30 (13-54) at discontinuation of ASV vs. 46 (24-67) (MLHFQ) at study end, p = 0.04. Though there was no significant change in NYHA functional class, patients especially reported increased shortness of breath, reduced concentration and reduced memory after discontinuation of ASV treatment. There were no significant differences in LVEF, heart rhythm data and physical capacity. Left ventricular function was preserved indicating that discontinuation of ASV in heart failure patients does not affect cardiac capacity. There was a significant decrement in QOL that must be considered in further treatment of these patients.

Quality of life improves in patients with chronic heart failure and Cheyne-Stokes respiration treated with adaptive servo-ventilation in a nurse-led heart failure clinic

AIMS AND OBJECTIVES

The aim of this study was to investigate if quality of life improved in chronic heart failure patients with Cheyne-Stokes respiration treated with adaptive servo-ventilation in nurse-led heart failure clinic.

BACKGROUND

Cheyne-Stokes respiration is associated with decreased quality of life in patients with chronic heart failure. Adaptive servo-ventilation is introduced to treat this sleep-disordered breathing.

DESIGN

Randomised, controlled design.

METHODS

Fifty-one patients (ranging from 53-84 years), New York Heart Association III-IV and/or left ventricular ejection fraction ≤40% and Cheyne-Stokes respiration were randomised to an intervention group who received adaptive servo-ventilation or a control group. Minnesota Living with Heart Failure Questionnaire was used to assess quality of life at randomisation and after three months. Both groups were followed in the nurse-led heart failure clinic.

RESULT

Adaptive servo ventilation improved quality of life-scores both in a per protocol analysis and in an intention to treat analysis. Twenty-one patients dropped out of the study, nine in the control and 12 in the intervention group.

CONCLUSION

Use of adaptive servo-ventilation improved quality of life in chronic heart failure patients with Cheyne-Stokes respiration. However, the drop-out rate was high.

RELEVANCE TO CLINICAL PRACTICE

Chronic heart failure patients come regularly to the nurse-led heart failure clinic. The heart failure nurses' competency has to include knowledge of equipment to provide support and continuity of care to the patients.

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.

Noninvasive Positive Pressure Ventilation in Chronic Heart Failure

Instruction and Objectives. Noninvasive positive pressure ventilation (NPPV) alleviates sleep-disordered breathing (SDB) and it may improve cardiac function in SDB patients. Because large randomized controlled trials directly evaluating the impact of NPPV on cardiac function are lacking, we conducted a meta-analysis of published data on effectiveness of NPPV in improving cardiac function in patients with chronic heart failure regardless of SDB presence. Methods. Controlled trials were identified in PubMed, OVID, and EMBASE databases. Both fixed and randomized models were used in meta-analysis with primary outcomes of left ventricular ejection fraction (LVEF). Results. Nineteen studies were included with a total of 843 patients. Compared to standard medical treatment (SMT) plus sham-NPPV or SMT only, NPPV plus SMT was associated with improvement in LVEF (weighted mean difference 5.34, 95% CI, [3.85,6.82]; P < 0.00001) and plasma brain natriuretic peptide (BNP) level (weighted mean difference -117.37, 95% CI, [-227.22, -7.52]; P = 0.04) and no influence on overall mortality (RR 1.00, 95% CI, [0.96,1.04]; P = 0.95). Conclusions. In the present meta-analysis, use of NPPV plus SMT improved LVEF and reduced plasma BNP level but did not improve overall mortality in patients with chronic heart failure.

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.

Adaptive servo-ventilation therapy of central sleep apnoea and its effect on sleep quality

OBJECTIVES

Poor sleep quality is common in patients with chronic heart failure (CHF). This study tested the hypothesis that adaptive servo-ventilation (ASV) therapy in CHF patients whose central sleep apnoea (CSA) was not suppressed by continuous positive airway pressure (CPAP) (CPAP-non-responders) would improve sleep quality compared to CPAP-responders receiving ongoing CPAP therapy.

METHODS

Eighty-two patients with CHF (65 ± 9 years, left ventricular ejection fraction 35 ± 16 %) and CSA [apnoea-hypopnoea index (AHI) ≥15/h] were retrospectively studied. Within an average of 47 days, patients were reevaluated on CPAP therapy and stratified according to their suppression of CSA: 34 were CPAP-non-responders switched to ASV therapy the following day and 48 were CPAP-responders who continued on CPAP therapy. Polysomnographic parameters were assessed in the diagnostic night and on the last night of PAP therapy (CPAP or ASV) before the patient was discharged with the final pressure settings.

RESULTS

Compared with the CPAP group, the ASV group had significantly greater reductions from baseline in AHI (-37 ± 15/h vs -28 ± 18/h, p = 0.02), arousal index (-12.7 ± 13.6/h vs -6.8 ± 12.5/h, p = 0.04) and sleep stage N1 (-9 ± 14 % vs -2 ± 12 %, p = 0.03). In addition, the ASV group gained significantly more rapid eye movement (REM) sleep compared with the CPAP group (+5 ± 9 % vs +1 ± 9 %, p = 0.02).

CONCLUSIONS

CPAP therapy is effective in reducing AHI in a significant proportion of CHF patients with reduced ejection fraction and CSA. Treatment of CSA with ASV in CHF patients reduces sleep fragmentation and improves sleep structure to a significantly greater extent than changes seen in responders to CPAP therapy.

Sleep-disordered breathing in patients with heart failure: new trends in therapy

Heart failure (HF) is a growing health problem which paradoxically results from the advances in the treatment of etiologically related diseases (especially coronary artery disease). HF is commonly accompanied by sleep-disordered breathing (SDB), which may directly exacerbate the clinical manifestations of cardiovascular disease and confers a poorer prognosis. Obstructive sleep apnoea predominates in mild forms while central sleep apnoea in more severe forms of heart failure. Identification of SDB in patients with HF is important, as its effective treatment may result in notable clinical benefits to the patients. Continuous positive airway pressure (CPAP) is the gold standard in the management of SDB. The treatments for central breathing disorders include CPAP, bilevel positive airway pressure (BPAP), and adaptive servoventilation (ASV), with the latter being the most modern method of treatment for the Cheyne-Stokes respiration and involving ventilation support with a variable synchronisation dependent on changes in airflow through the respiratory tract and on the patient's respiratory rate. ASV exerts the most favourable effect on long-term prognosis. In this paper, we review the current state of knowledge on the diagnosis and treatment of SDB with a particular emphasis on the latest methods of treatment.

Adaptive servoventilation for treatment of sleep-disordered breathing in heart failure: a systematic review and meta-analysis

BACKGROUND

Adaptive servoventilation (ASV) has demonstrated efficacy in treating sleep-disordered breathing (SDB) in patients with heart failure (HF), but large randomized trials are lacking. We, therefore, sought to perform a systematic review and meta-analysis of existing data.

METHODS

A systematic search of the PubMed database was undertaken in March 2012. Publications were independently assessed by two investigators to identify studies of ≥ 1-week duration that compared ASV to a control condition (ie, subtherapeutic ASV, continuous or bilevel pressure ventilation, oxygen therapy, or no treatment) in adult patients with SDB and HF. Mean, variability,and sample size data were extracted independently for the following outcomes: apneahypopnea index (AHI), left ventricular ejection fraction (LVEF), quality of life (SF-36 Health Survey; Medical Outcomes Trust), 6-min walk distance, peak oxygen consumption ( VO 2 ) % predicted, and ventilatory equivalent ratio for CO 2 ( VE / Vco 2 ) slope measured during exercise. Random effects meta-analysis models were applied.

RESULTS

Fourteen studies were identified (N = 538). Comparing ASV to control conditions, the weighted mean difference in AHI ( -14.64 events/h; 95% CI, -21.03 to - 8.25) and LVEF (0.40;95% CI, 0.08-0.71) both significantly favored ASV. ASV also improved the 6-min walk distance,but not peak O 2 % predicted, VE / VCO 2 slope, or quality of life, compared with control conditions.

CONCLUSIONS

In patients with HF and SDB, ASV was more effective than control conditions in reducing the AHI and improving cardiac function and exercise capacity. These data provide a compelling rationale for large-scale randomized controlled trials to assess the clinical impact of ASV on hard outcomes in these patients.

The treatment of central sleep apnea syndromes in adults: practice parameters with an evidence-based literature review and meta-analyses

The International Classification of Sleep Disorders, Second Edition (ICSD-2) distinguishes 5 subtypes of central sleep apnea syndromes (CSAS) in adults. Review of the literature suggests that there are two basic mechanisms that trigger central respiratory events: (1) post-hyperventilation central apnea, which may be triggered by a variety of clinical conditions, and (2) central apnea secondary to hypoventilation, which has been described with opioid use. The preponderance of evidence on the treatment of CSAS supports the use of continuous positive airway pressure (CPAP). Much of the evidence comes from investigations on CSAS related to congestive heart failure (CHF), but other subtypes of CSAS appear to respond to CPAP as well. Limited evidence is available to support alternative therapies in CSAS subtypes. The recommendations for treatment of CSAS are summarized as follows: CPAP therapy targeted to normalize the apnea-hypopnea index (AHI) is indicated for the initial treatment of CSAS related to CHF. (STANDARD)Nocturnal oxygen therapy is indicated for the treatment of CSAS related to CHF. (STANDARD)Adaptive Servo-Ventilation (ASV) targeted to normalize the apnea-hypopnea index (AHI) is indicated for the treatment of CSAS related to CHF. (STANDARD)BPAP therapy in a spontaneous timed (ST) mode targeted to normalize the apnea-hypopnea index (AHI) may be considered for the treatment of CSAS related to CHF only if there is no response to adequate trials of CPAP, ASV, and oxygen therapies. (OPTION)The following therapies have limited supporting evidence but may be considered for the treatment of CSAS related to CHF after optimization of standard medical therapy, if PAP therapy is not tolerated, and if accompanied by close clinical follow-up: acetazolamide and theophylline. (OPTION)Positive airway pressure therapy may be considered for the treatment of primary CSAS. (OPTION)Acetazolamide has limited supporting evidence but may be considered for the treatment of primary CSAS. (OPTION)The use of zolpidem and triazolam may be considered for the treatment of primary CSAS only if the patient does not have underlying risk factors for respiratory depression. (OPTION)The following possible treatment options for CSAS related to end-stage renal disease may be considered: CPAP, supplemental oxygen, bicarbonate buffer use during dialysis, and nocturnal dialysis. (OPTION) .

Sleep disordered breathing in patients with heart failure: pathophysiology and management

OPINION STATEMENT

Sleep disordered breathing (SDB) is common in heart failure patients across the range of ejection fractions and is associated with adverse prognosis. Although effective pharmacologic and device-based treatment of heart failure may reduce the frequency or severity of SDB, heart failure treatment alone may not be adequate to restore normal breathing during sleep. Continuous positive airway pressure (CPAP) is the major treatment for SDB in heart failure, especially if obstructive rather than central sleep apnea (CSA) predominates. Adequate suppression of CSA by PAP is associated with a heart transplant-free survival benefit, although randomized trials are ongoing. Bilevel PAP (BPAP) may be as effective as CPAP in treating SDB and may be preferable over CPAP in patients who experience expiratory pressure discomfort. Adaptive (or auto) servo-ventilation (ASV), which adjusts the PAP depending on the patient's airflow or tidal volume, may be useful in congestive heart failure patients if CPAP is ineffective. Other therapies that have been proposed for SDB in congestive heart failure include nocturnal oxygen, CO(2) administration (by adding dead space), theophylline, and acetazolamide; most of which have not been systematically studied in outcome-based prospective randomized trials.

Adaptive servoventilation improves cardiac function and respiratory stability

Cheyne–Stokes respiration (CSR) in patients with chronic heart failure (CHF) is of major prognostic impact and expresses respiratory instability. Other parameters are daytime pCO₂, VE/VCO₂-slope during exercise, exertional oscillatory ventilation (EOV), and increased sensitivity of central CO₂ receptors. Adaptive servoventilation (ASV) was introduced to specifically treat CSR in CHF. Aim of this study was to investigate ASV effects on CSR, cardiac function, and respiratory stability. A total of 105 patients with CHF (NYHA ≥ II, left ventricular ejection fraction (EF) ≤ 40%) and CSR (apnoea–hypopnoea index ≥ 15/h) met inclusion criteria. According to adherence to ASV treatment (follow-up of 6.7 ± 3.2 months) this group was divided into controls (rejection of ASV treatment or usage <50% of nights possible and/or <4 h/night; n = 59) and ASV (n = 56) adhered patients. In the ASV group, ventilator therapy was able to effectively treat CSR. In contrast to controls, NYHA class, EF, oxygen uptake, 6-min walking distance, and NT-proBNP improved significantly. Moreover, exclusively in these patients pCO₂, VE/VCO₂-slope during exercise, EOV, and central CO₂ receptor sensitivity improved. In CHF patients with CSR, ASV might be able to improve parameters of SDB, cardiac function, and respiratory stability.

Adaptive servoventilation improves cardiac function in patients with chronic heart failure and Cheyne-Stokes respiration

BACKGROUND AND AIMS

Sleep disordered breathing (SDB), especially Cheyne-Stokes respiration (CSR) is common in patients with chronic heart failure (CHF). Adaptive servoventilation (ASV) was recently introduced to treat CSR in CHF. The aim of this study was to investigate the effects of ASV on CSR and CHF parameters.

METHODS

In 29 male patients (63.9+/-9 years, NYHA> or =II, left ventricular ejection fraction [LV-EF]< or =40%), cardiorespiratory polygraphy, cardiopulmonary exercise (CPX) testing, and echocardiography were performed and concentrations of NT-proBNP determined before and after 5.8+/-3.5 months (median 5.7 months) of ASV (AutoSet CS2, ResMed) treatment. All patients also received guideline-driven CHF therapy.

RESULTS

Apnoea-hypopnoea-index was reduced from 37.4+/-9.4/h to 3.9+/-4.1/h (p<0.001). Workload during CPX testing increased from 81+/-26 to 100+/-31 W (p=0.005), oxygen uptake (VO2) at the anaerobic threshold from 12.6+/-3 to 15.3+/-4 ml/kg/min (p=0.01) and predicted peak VO2 from 58+/-12% to 69+/-17% (p=0.007). LV-EF increased from 28.2+/-7% to 35.2+/-11% (p=0.001), and NT-proBNP levels decreased significantly (2285+/-2192 pg/ml to 1061+/-1293 pg/ml, p=0.01).

CONCLUSIONS

In selected patients with CHF and CSR, addition of ASV to standard heart failure therapy is able to improve SDB, CPX test results, LV-EF and NT-proBNP concentrations.