Sleep Apnea in Heart Failure

Sleep apnea in patients with exacerbated heart failure and overweight

Sleep disorders are a common concomitant comorbidity in patients with heart failure. The aims of our study are to determine the incidence and phenotypic characteristics of sleep apnea in overweight patients with exacerbated heart failure and to assess the degree of involvement of systolic and diastolic function impairment in the individual group. From 100 screened patients with heart failure in our department from 2015 to 2017, 61 met the inclusion criteria and participated in the study. 82% (n = 50) of the patients had obstructive sleep apnea (OSA), and 18% (n = 11) had central sleep apnea (CSA). The CSA group had a significantly lower left ventricular ejection fraction (LVEF) than the OSA group (EF% 49.6 ± 8.5 vs 41.8 ± 11.4; p = 0.013). A negative correlation was found between LVEF and the number of central apnea events (r = -0.52; p < 0.001). More frequent hospitalizations for heart failure (HF) and higher mortality rate were found in the CSA group. Screening for sleep apnea in patients with exacerbated heart failure and obesity is necessary for the complex treatment of these patients.

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.

Obstructive sleep apnea: personalizing CPAP alternative therapies to individual physiology

Introduction The recent continuous positive airway pressure (CPAP) crisis has highlighted the need for alternative obstructive sleep apnea (OSA) therapies. This article serves to review OSA pathophysiology and how sleep apnea mechanisms may be utilized to individualize alternative treatment options.Areas covered: The research highlighted below focuses on 1) mechanisms of OSA pathogenesis and 2) CPAP alternative therapies based on mechanism of disease. We reviewed PubMed from inception to July 2022 for relevant articles pertaining to OSA pathogenesis, sleep apnea surgery, as well as sleep apnea alternative therapies.Expert opinion: Although the field of individualized OSA treatment is still in its infancy, much has been learned about OSA traits and how they may be targeted based on a patient's physiology and preferences. While CPAP remains the gold-standard for OSA management, several novel alternatives are emerging. CPAP is a universal treatment approach for all severities of OSA. We believe that a personalized approach to OSA treatment beyond CPAP lies ahead. Additional research is needed with respect to implementation and combination of therapies longitudinally, but we are enthusiastic about the future of OSA treatment based on the data presented here.

Obstructive sleep apnea and right ventricular function: A meta-analysis of speckle tracking echocardiographic studies

The authors investigated the association between obstructive sleep apnea (OSA) and right ventricular (RV) systolic dysfunction trough a meta‐analysis of echocardiographic studies providing data on RV mechanics as assessed by longitudinal strain (LS). A systematic search was conducted using PubMed, OVID‐MEDLINE, and Cochrane library databases to search English‐language review papers published from inception to March 31, 2022. Only studies reporting data on RV free‐wall or global LS in patients with OSA of different severity and non‐OSA controls were reviewed. Data of interest were pooled to obtain standard means difference (SMD) with 95% confidence interval (CI). The meta‐analysis included 628 participants (436 with OSA and 192 controls) from eight studies. Compared to controls, RV free wall LS was significantly reduced in the pooled OSA group (SMD 1.02 ± .33, CI:.17/1.24, P < .002); this was also the case for RV global LS (SMD: .72 ± .11, CI: .50/.93, P < .0001). Notably, compared to patients with mild‐OSA those with moderate and severe OSA exhibited significantly lower RV free‐wall LS and global LS values; this was not the case for tricuspid annular plane excursion. In conclusions, both RV free‐wall and global LS are impaired in patients with OSA; deterioration of these indices, unlike TAPSE, was already evident in the early stages and was related to the severity of the syndrome. Thus, RV myocardial strain should be considered to be included in echocardiographic evaluation of OSA patients in order to detect subclinical cardiac damage in these patients regardless of its degree of severity.

Dynamic models of obstructive sleep apnea provide robust prediction of respiratory event timing and a statistical framework for phenotype exploration

Obstructive sleep apnea (OSA), in which breathing is reduced or ceased during sleep, affects at least 10% of the population and is associated with numerous comorbidities. Current clinical diagnostic approaches characterize severity and treatment eligibility using the average respiratory event rate over total sleep time (apnea-hypopnea index). This approach, however, does not characterize the time-varying and dynamic properties of respiratory events that can change as a function of body position, sleep stage, and previous respiratory event activity. Here, we develop a statistical model framework based on point process theory that characterizes the relative influences of all these factors on the moment-to-moment rate of event occurrence. Our results provide new insights into the temporal dynamics of respiratory events, suggesting that most adults have a characteristic event pattern that involves a period of normal breathing followed by a period of increased probability of respiratory event occurrence, while significant differences in event patterns are observed among gender, age, and race/ethnicity groups. Statistical goodness-of-fit analysis suggests consistent and substantial improvements in our ability to capture the timing of individual respiratory events using our modeling framework. Overall, we demonstrate a more statistically robust approach to characterizing sleep disordered breathing that can also serve as a basis for identifying future patient-specific respiratory phenotypes, providing an improved pathway towards developing individualized treatments.

Noncancerous Genitourinary Conditions as a Public Health Priority: Conceptualizing the Hidden Burden

OBJECTIVE

To provide a conceptual framework to guide investigations into burdens of noncancerous genitourinary conditions (NCGUCs), which are extensive and poorly understood.

METHODS

The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop of diverse, interdisciplinary researchers and health professionals to identify known and hidden burdens of NCGUCs that must be measured to estimate the comprehensive burden. Following the meeting, a subgroup of attendees (authors of this article) continued to meet to conceptualize burden.

RESULTS

The Hidden Burden of Noncancerous Genitourinary Conditions Framework includes impacts across multiple levels of well-being and social ecology, including individual (ie, biologic factors, lived experience, behaviors), interpersonal (eg, romantic partners, family members), organizational/institutional (eg, schools, workplaces), community (eg, public restroom infrastructure), societal (eg, health care and insurance systems, national workforce/economic output), and ecosystem (eg, landfill waste) effects. The framework acknowledges that NCGUCs can be a manifestation of underlying biological dysfunction, while also leading to biological impacts (generation and exacerbation of health conditions, treatment side effects).

CONCLUSION

NCGUCs confer a large, poorly understood burden to individuals and society. An evidence-base to describe the comprehensive burden is needed. Measurement of NCGUC burdens should incorporate multiple levels of well-being and social ecology, a life course perspective, and potential interactions between NCGUCs and genetics, sex, race, and gender. This approach would elucidate accumulated impacts and potential health inequities in experienced burdens. Uncovering the hidden burden of NCGUCs may draw attention and resources (eg, new research and improved treatments) to this important domain of health.

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.

Temporal trends in outcome and patient characteristics in dilated cardiomyopathy, data from the Swedish Heart Failure Registry 2003-2015

Background

Temporal trends in clinical composition and outcome in dilated cardiomyopathy (DCM) are largely unknown, despite considerable advances in heart failure management. We set out to study clinical characteristics and prognosis over time in DCM in Sweden during 2003–2015.

Methods

DCM patients (n = 7873) from the Swedish Heart Failure Registry were divided into three calendar periods of inclusion, 2003–2007 (Period 1, n = 2029), 2008–2011 (Period 2, n = 3363), 2012–2015 (Period 3, n = 2481). The primary outcome was the composite of all-cause death, transplantation and hospitalization during 1 year after inclusion into the registry.

Results

Over the three calendar periods patients were older (p = 0.022), the proportion of females increased (mean 22.5%, 26.4%, 27.6%, p = 0.0001), left ventricular ejection fraction was higher (p = 0.0014), and symptoms by New York Heart Association less severe (p < 0.0001). Device (implantable cardioverter defibrillator and/or cardiac resynchronization) therapy increased by 30% over time (mean 11.6%, 12.3%, 15.1%, p < 0.0001). The event rates for mortality, and hospitalization were consistently decreasing over calendar periods (p < 0.0001 for all), whereas transplantation rate was stable. More advanced physical symptoms correlated with an increased risk of a composite outcome over time (p = 0.0043).

Conclusions

From 2003 until 2015, we observed declining mortality and hospitalizations in DCM, paralleled by a continuous change in both demographic profile and therapy in the DCM population in Sweden, towards a less affected phenotype.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02124-0.

Epicardial Adipose Tissue in Patients with Obstructive Sleep Apnea: A Systematic Review and Meta-analysis

Objective: Epicardial adipose tissue (EAT) is a potential risk factor for obstructive sleep apnea (OSA). We performed a meta-analysis to assess the association of EAT with OSA.Methods: The PubMed, EMBASE, Web of Science, Cochrane Library, and Wanfang databases were searched by two independent investigators for all observational studies assessing the association of EAT with OSA. Then we assessed the association of EAT thickness (EAT-t) and EAT volume (EAT-v) with OSA by a meta-analysis.Results: Ten studies were included in the final analysis. Compared with that in controls, EAT-t in OSA patients was significantly increased (standardized mean difference 0.88, 95% confidence interval 0.72‐1.05, P=0.000). Furthermore, EAT-t was greater in OSA patients than in controls with similar BMIs. However, we did not find significant differences in EAT-v between OSA patients and controls (standardized mean difference 2.46, 95% confidence interval −0.36 to 5.29, P=0.088). EAT-t in the mild, moderate, and severe OSA subgroups was greater than in the controls. In addition, there were significant differences in EAT-t among the mild, moderate, and severe OSA subgroups.Conclusions: EAT-t was greater in patients with OSA than in controls, and EAT-t was also associated with the severity of OSA. These findings may provide a new clue for the pathogenesis and treatment of OSA.

Obstructive sleep apnea versus central sleep apnea: prognosis in systolic heart failure

Background

In chronic heart failure (CHF), obstructive sleep apnea (OSA) and Cheyne-Stokes respiration (CSR) are associated with increased mortality. The present study aimed to evaluate the prognostic effect of CSR compared to OSA, in otherwise similar groups of CHF patients.

Methods

Screening for sleep-disordered breathing (SDB) was conducted among patients with CHF of New York Heart Association (NYHA) class II-IV, and left ventricular ejection fraction (LVEF) of ≤45%. The study included 43 patients (4 women) with >25% CSR during sleeping time, and 19 patients (2 women) with OSA and an apnea-hypopnea index (AHI) of ≥6. Patients were followed for a median of 1,371 days. The primary endpoint was mortality, and the secondary endpoint was combined mortality and hospital admissions.

Results

Baseline parameters did not significantly differ between groups, but CSR patients were older and had higher AHI values than OSA patients. Five OSA patients (26%) died, and 14 (74%) met the combined end-point of death or hospitalization. CSR patients had significantly higher risk for both end-points, with 23 (53%) deaths [log-rank P=0.040; HR, 2.70 (1.01-7.22); P=0.047] and 40 (93%) deaths or readmissions [log-rank P=0.029; HR, 1.96 (1.06-3.63); P=0.032]. After adjustment for confounding risk factors, the association between CSR and death remained significant [HR, 4.73 (1.10-20.28); P=0.037], hospital admission rates were not significantly different.

Conclusions

Among patients with CHF, CSR was associated with higher mortality than OSA independently of age and cardiac systolic function. CSR was also an age-independent predictor of unfavorable outcome, but hospital admission rates were not significantly different between the two groups after adjustment.

In-Hospital Management of Sleep Apnea During Heart Failure Hospitalization: A Randomized Controlled Trial

BACKGROUND

Obstructive sleep apnea (OSA) is associated with increased mortality and readmissions in patients with heart failure (HF). The effect of in-hospital diagnosis and treatment of OSA during decompensated HF episodes remains unknown.

METHODS AND RESULTS

A single-site, randomized, controlled trial of hospitalized patients with decompensated HF (n = 150) who were diagnosed with OSA during the hospitalization was undertaken. All participants received guideline-directed therapy for HF decompensation. Participants were randomized to an intervention arm which received positive airway pressure (PAP) therapy during the hospitalization (n = 75) and a control arm (n = 75). The primary outcome was discharge left ventricular ejection fraction (LVEF). The LVEF changed in the PAP arm from 25.5 ± 10.4 at baseline to 27.3 ± 11.9 at discharge. In the control group, LVEF was 27.3 ± 11.7 at baseline and 28.8 ± 10.5 at conclusion. There was no significant effect on LVEF of in-hospital PAP compared with controls (P = .84) in the intention-to-treat analysis. The on-treatment analysis in the intervention arm showed a significant increase in LVEF in participants who used PAP for ≥3 hours per night (n = 36, 48%) compared with those who used it less (P = .01). There was a dose effect with higher hours of use associated with more improvement in LVEF. Follow-up of readmissions at 6 months after discharge revealed a >60% decrease in readmissions for patients who used PAP ≥3 h/night compared with those who used it <3 h/night (P < .02) and compared with controls (P < .04).

CONCLUSIONS

In-hospital treatment with PAP was safe but did not significantly improve discharge LVEF in patients with decompensated HF and newly diagnosed OSA. An exploratory analysis showed that adequate use of PAP was associated with higher discharge LVEF and decreased 6 months readmissions.

Unilateral phrenic nerve stimulation in the therapeutical algorithm of central sleep apnoea in heart failure

PURPOSE OF REVIEW

Central sleep apnoea (CSA) is highly prevalent in patients with heart failure and substantially impairs survival. If optimal cardiac treatment fails, alternative therapeutical options, including positive airway pressure (PAP) therapies, drugs or application of oxygen and carbon dioxide are considered to suppress CSA which interfere with the complex underlying pathophysiology. Most recently, unilateral phrenic nerve stimulation (PNS) has been studied in these patients. Therefore, there is an urgent need to critically evaluate efficacy, potential harm and positioning of PNS in current treatment algorithms.

RECENT FINDINGS

Data from case series and limited randomized controlled trials demonstrate the feasibility of the invasive approach and acceptable peri-interventional adverse events. PNS reduces CSA by 50%, a figure comparable with continuous PAP or oxygen. However, PNS cannot improve any comorbid upper airways obstruction. A number of fatalities due to malignant cardiac arrhythmias or other cardiac events have been reported, although the association with the therapy is unclear.

SUMMARY

PNS offers an additional option to the therapeutical portfolio. Intervention-related adverse events and noninvasive alternatives need clear discussion with the patient. The excess mortality in the SERVE-HF study has mainly been attributed to sudden cardiac death. Therefore, previous cardiac fatalities under PNS urge close observation in future studies as long-term data are missing.

Quantifying statistical uncertainty in metrics of sleep disordered breathing

BACKGROUND

The apnea-hypopnea index (AHI) (or one of its derivatives) is the primary clinical metric for characterizing sleep disordered breathing-the value of which with respect to a threshold determines severity of diagnosis and eligibility for treatment reimbursement. The index value, however, is taken as a perfect point estimate, with no measure of statistical uncertainty. Thus, current practice does not robustly account for variability in diagnosis/eligibility due to chance. In this paper, we quantify the statistical uncertainty associated with respiratory event indices for sleep disordered breathing and the effect of uncertainty on treatment eligibility.

METHODS

We develop an empirical estimate of uncertainty using a non-parametric bootstrap on the interevent times, as well as a theoretical Poisson estimate reflecting the current formulation of the AHI. We then apply these methods to estimate AHI uncertainty for 2049 subjects (954/1095 M/F, age: mean 69 ± 9.1) from the Multi-Ethnic Study of Atherosclerosis (MESA).

RESULTS AND CONCLUSIONS

The mean 95% empirical confidence interval width was 11.500 ± 6.208 events per hour and the mean 95% theoretical Poisson confidence interval width was 5.998 ± 2.897 events per hour, suggesting that uncertainty is likely a major confounding factor within the current diagnostic framework. Of the 278 subjects in the symptomatic population (ESS>10), 27% (76/278) had uncertain diagnoses given the 95% empirical confidence interval. Of the 2049 subjects in the full population, 43% (880/2049) had uncertain diagnoses given the 95% empirical confidence interval. The inclusion of subjects with uncertain diagnoses increases the number of eligible patients by 21.3% for the symptomatic population and by 84.8% for the full population. The exclusion of subjects with uncertain diagnoses given the 95% empirical confidence interval decreases the number of eligible patients by 12.4% for the symptomatic population and by 34.8% for full population. Additional analyses suggest that it is practically infeasible to gain diagnostic statistical significance through additional testing for a broad range of borderline cases. Overall, these results suggest that AHI uncertainty is a vital additional piece of information that would greatly benefit clinical practice, and that the inclusion of uncertainty in epidemiological analysis might help improve the ability for researchers to robustly link AHI with co-morbidities and long-term outcomes.

Sleepless nights and sleepy days: a qualitative study exploring the experiences of patients with chronic heart failure and newly verified sleep-disordered breathing

BACKGROUND

Sleep-disordered breathing, including obstructive sleep apnoea and central sleep apnoea, is a common disorder among patients with chronic heart failure. Obstructive sleep apnoea is often treated with continuous positive airway pressure, but central sleep apnoea lacks a clear treatment option. Knowledge of how sleep-disordered breathing is experienced (e.g. difficulties and care needs) and handled (e.g. self-care actions) by the patients is limited, but needed, to provide patient-centred care.

AIM

To explore how newly verified sleep-disordered breathing is experienced by patients with chronic heart failure.

METHODS

Data were collected through semi-structured interviews and analysed with qualitative content analysis. Seventeen participants (14 men, three women), mean age 60 years (range 41-80) diagnosed with chronic heart failure and objectively verified sleep-disordered breathing (nine obstructive, seven central and one mixed) were strategically selected from heart failure outpatient clinics at two Norwegian university hospitals.

RESULTS

Patients with chronic heart failure and newly verified sleep-disordered breathing (SDB) described experiences of poor sleep that had consequences for their daily life and their partners. Different self-care strategies were revealed, but they were based on 'common sense' and were not evidence-based. The awareness of having SDB was varied; for some, it gave an explanation to their trouble while others were surprised by the finding.

CONCLUSION

Patients with chronic heart failure and sleep-disordered breathing experienced reduced sleep quality, influencing their daily life. Possible underlying causes of disrupted sleep, such as sleep-disordered breathing, should be identified to establish proper patient-centred treatment strategies. There is a need for new strategies to approach patients with chronic heart failure (i.e. those with central sleep apnoea) who are not subject to continuous positive airway pressure treatment for their sleep-disordered breathing.