Beneficial Effects of Positive Airway Pressure Therapy for Sleep-Disordered Breathing in Heart Failure Patients With Preserved Left Ventricular Ejection Fraction

Heart Failure with Preserved Ejection Fraction: How to Deal with This Chameleon

Heart failure with preserved ejection fraction (HFpEF) is characterized by a notable heterogeneity in both phenotypic and pathophysiological features, with a growing incidence due to the increase in median age and comorbidities such as obesity, arterial hypertension, and cardiometabolic disease. In recent decades, the development of new pharmacological and non-pharmacological options has significantly impacted outcomes, improving clinical status and reducing mortality. Moreover, a more personalized and accurate therapeutic management has been demonstrated to enhance the quality of life, diminish hospitalizations, and improve overall survival. Therefore, assessing the peculiarities of patients with HFpEF is crucial in order to obtain a better understanding of this disorder. Importantly, comorbidities have been shown to influence symptoms and prognosis, and, consequently, they should be carefully addressed. In this sense, it is mandatory to join forces with a multidisciplinary team in order to achieve high-quality care. However, HFpEF remains largely under-recognized and under-treated in clinical practice, and the diagnostic and therapeutic management of these patients remains challenging. The aim of this paper is to articulate a pragmatic approach for patients with HFpEF focusing on the etiology, diagnosis, and treatment of HFpEF.

Prognostic Effects of Changes in Right Ventricular Fractional Area Change in Patients With Heart Failure

BACKGROUND

It is still unclear whether changes in right ventricular function are associated with prognosis in heart failure (HF) patients. This study aimed to examine the prognostic effect of changes in right ventricular fractional area change (RVFAC).

METHODS AND RESULTS

This study enrolled 480 hospitalized patients with decompensated HF, and measured RVFAC with echocardiography at discharge (first examination) and post-discharge in the outpatient setting (second examination). RVFAC was divided into 3 categories: >35% in 314 patients, 25-35% in 108 patients, and <25% in 58 patients. Next, based on changes in RVFAC from the first to the second examination, the patients were further classed into 4 groups: (1) Preserved/Unchanged (preserved and unchanged RVFAC, n=235); (2) Reduced/Improved (improved RVFAC in at least 1 category, n=106); (3) Reduced/Unchanged (reduced and unchanged RVFAC, n=47); and (4) Preserved or Reduced/Worsened (deteriorated RVAFC in at least 1 category, n=92). Multivariate logistic regression analysis revealed that chronic kidney disease and anemia were the predictors of the preserved or reduced/worsened RVFAC. In the Kaplan-Meier analysis, changes in RVFAC were associated with the cardiac event rate and all-cause mortality. In the multivariable Cox proportional hazard analysis, the preserved or reduced/worsened RVFAC was an independent predictor of cardiac events and all-cause mortality.

CONCLUSIONS

Changes in RVFAC were associated with post-discharge prognosis in hospitalized heart failure patients.

Temporal Trends in the Practice Pattern for Sleep-Disordered Breathing in Patients With Cardiovascular Diseases in Japan - Insights From the Japanese Registry of All Cardiac and Vascular Diseases - Diagnosis Procedure Combination

BACKGROUND

After the publication of the Japanese Circulation Society guideline of sleep-disordered breathing (SDB) in 2010, with new evidence and changes to the health insurance system, trends in the practice pattern for SDB in patients with cardiovascular disease (CVD) might have changed.

METHODS AND RESULTS

This study evaluated the temporal changes in the practice pattern for SDB by using a nationwide claim database, the Japanese Registry of All Cardiac and Vascular Diseases - Diagnosis Procedure Combination (JROAD-DPC), from 2012 to 2019. The main findings were: (1) the number of CVD patients diagnosed with SDB increased (especially those with atrial fibrillation [AF] and heart failure [HF]); (2) the number of diagnostic tests for SDB performed during hospitalization increased for AF patients (from 1.3% in 2012 to 1.8% in 2019), whereas it decreased for other CVD patients; (3) the number of patients diagnosed with SDB increased in each type of CVD, except for patients with acute myocardial infarction (AMI); (4) continuous positive airway pressure (CPAP) treatment increased for AF patients (from 15.2% to 17.5%); (5) CPAP treatment decreased for patients with angina pectoris (AP) and AMI, and any treatment decreased for HF patients (from 46.1% to 39.7%); and (6) SDB was treated more often in HF patients than in AF, AP, and AMI patients (41.7% vs. 17.2%, 19.1% and 20.4%, respectively).

CONCLUSIONS

The practice pattern for SDB in CVD patients has changed from 2012 to 2019.

Cheyne-Stokes Breathing as a Predictive Indicator of Heart Failure in Patients With Obstructive Sleep Apnea; A Retrospective Case Control Study Using Continuous Positive Airway Pressure Remote Monitoring Data

Objective

We conducted a retrospective case control study to examine whether remote monitoring of Cheyne-Stokes breathing (CSB) was useful for predicting the onset of heart failure (HF) in patients with obstructive sleep apnea (OSA) on continuous positive airway pressure (CPAP).

Methods

Among patients with OSA treated at our hospital, 33 patients with HF that occurred between July 2014 and May 2021 [11 patients with acute HF (AHF); 22 patients with chronic HF (CHF) exacerbation] were included in the HF group. Of the 618 stable patients, 149 patients with a 30-days average CSB rate (CSB%) ≧1% were included in the non-HF control group. The chronologic change of CSB% were compared among the AHF, CHF and Control groups. Furthermore, of the 149 patients in the non-HF control group, 44 patients were matched for CSB%, body mass index, and sex in a ratio of 1:2 to 22 patients with CHF. The average cycle length (CL) of CSB was compared among three groups: CHF in stable period (CHF-stable group), CHF in exacerbation period (CHF-exacerbation group), and control group. In addition, according to the status of HF, receiver operating characteristic (ROC) curves were generated to determine the optimal cut-off points for variation of CSB% and CL.

Results

Chronological change in CSB% among the three groups was significantly different. Standard deviation of CSB% (SD CSB%) before onset HF was significantly higher in both the AHF and CHF groups than in the control group. The CL of CSB was significantly longer in the CHF group than in the control group and was longer during the exacerbation period than during the stable period. The optimal cut-off value of CL that could differentiate patients with and without the onset of HF was 68.9 s.

Conclusion

The HF group demonstrated greater CSB variations and longer CL than the non-HF control group. Furthermore, the CL was longer during the exacerbation period of HF even in the same patient. These results suggest that remote monitoring of CPAP device data for CSB variations and CL might allow early prediction of the onset and exacerbation of HF.

Continuous positive airway pressure treatment in sleep apnea: patient compliance and impact on the right heart

Obstructive sleep apnea syndrome (OSAS) is considered to be an important predisposing factor for cardiovascular diseases. The main objective of this study was to investigate the impact of CPAP treatment on cardiac structure and function and to assess patient compliance over a long-term course of CPAP treatment. A total of 50 patients diagnosed with moderate-to-severe OSAS based on overnight study, without relevant concomitant diseases were enrolled. Patient compliance, along with echocardiographic and CPAP parameters, was assessed. The average time to follow-up was 38 ± 4.2 months. An increase in tricuspid annular plane systolic excursion (TAPSE) (22.1 ± 4.3-25.5 ± 4.6 mm, p = 0.005) and peak early systolic tricuspid annular velocity (S') (14 ± 3.2-17.2 ± 5.2 cm/s, p = 0.005) after CPAP treatment was noted. In patients without CPAP, no significant change in right ventricular (RV) contractility was found. There were no significant differences regarding right atrial (RA) and RV diameters, as well as tricuspid regurgitant peak gradient (TRPG) in both groups; however, a predisposition to increased RA size along with RV and tricuspid annulus diameters was revealed. The mean duration of nightly CPAP use was 3 ± 2.3 h/night in all-day analysis and 4.7 ± 2.1 h/night on days with device usage. The non-adherence rate was 57%. The use of effective CPAP therapy may lead to increased RV systolic function in patients with OSAS in long-term observation. However, long-term patient compliance is generally poor. Regardless of CPAP therapy, a gradual increase in heart size is observed.

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.

Positionspapier „Schlafmedizin in der Kardiologie“, Update 2021

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

Feasibility of Transcatheter Caval Valve Implantation to Improve -Disordered Breathing in Patients With Severe Tricuspid Regurgitation-A Pilot Study

Transcatheter caval valve implantation (CAVI) has been evaluated as a treatment option for inoperable patients with severe symptomatic tricuspid regurgitation (TR). We studied the effect of CAVI on sleep disorder breathing (SDB) in patients with right heart failure and TR. Twenty right heart failure patients with severe symptomatic TR who underwent portable monitoring of SDB (ApneaLink), echocardiography, cardiopulmonary exercise (CPET), and laboratory testing were enrolled. This was a single-center, nonblinded study. There were no significant changes in sleep variables, echocardiographic parameters, laboratory results, lung function, and CPET after CAVI. In conclusion, these data suggest that CAVI may not have an effect on SDB; however, additional follow-up fully powered studies with appropriate statistical analyses are needed.

Novel technologies in the management of heart failure with preserved ejection fraction: a promise during the time of disappointment from pharmacological approaches?

PURPOSE OF REVIEW

Despite numerous attempts, none of a wide variety of tested drugs achieved meaningful improvement in the outcomes of heart failure with preserved ejection fraction (HFpEF), making new therapeutic strategies a major unmet medical need. The medical device industry embraced the challenge, developing novel technologies directed to face specific aspects of the pathophysiology of HFpEF. This review focuses on some of the most promising technologies attaining meaningful clinical progress recently in the field of HFpEF therapy.

RECENT FINDINGS

Implantable pulmonary artery pressure, monitoring for optimization of medical therapy, proved to be beneficial in heart failure admissions in a large postmarketing clinical study. Investigational devices, such as inter-atrial shunts and transvenous phrenic nerve stimulators for the treatment of central sleep apnea with Cheyne-Stokes breathing, are currently being evaluated in HFpEF cohorts in recent trials.

SUMMARY

Device-based therapies for HFpEF demonstrated encouraging safety and efficacy results in various stages of the disease. Further efforts are needed to ensure that these devices will reach clinical use and contribute to the management of HFpEF patients.

Hypertension as a Road to Treatment of Heart Failure with Preserved Ejection Fraction

PURPOSE OF REVIEW

Hypertension heralds the diagnosis of heart failure (HF) with preserved ejection fraction (HFpEF) in 75-85% of cases and shares many of its adverse outcomes as well as its acute and chronic symptoms. This review provides important new data about the pathophysiology and mechanisms that connect hypertension and HFpEF as well as therapy used in both conditions.

RECENT FINDINGS

The traditional model of HFpEF pathophysiology emphasizes the role of hypertension causing increased afterload on the left ventricle (LV), leading to LV hypertrophy (LVH) and subsequent LV diastolic dysfunction. Recent work has provided valuable insights into the mechanisms underlying the transition from hypertension to HFpEF, showing that the pathophysiology extends beyond LVH and diastolic dysfunction. An evolving paradigm suggests that HFpEF is inflammatory in nature with multifactorial pathophysiology, affected by age-related changes and comorbidities. Hypertension shares many of the proinflammatory mechanisms of HFpEF. Furthermore, hypertension precedes HFpEF in the majority of cases. Because of its clinically heterogeneous nature, development of standardized therapies for HFpEF has been challenging. As there are standardized approaches to hypertension, we suggest that similar approaches be used for the treatment of HFpEF, including medical and non-medical therapies. With medical therapies, a treat-to-target blood pressure (BP) strategy could be employed, such as systolic BP < 130 mmHg. With non-medical therapies, approaches to deal with physical inactivity, obesity, and sleep apnea could be used. Due to its heterogeneity, delineation of standardized therapies for HFpEF has been challenging. Focusing on the tremendous overlap of hypertensive heart disease with HFpEF, it is proposed that approaches currently used to guide therapies for hypertension be applied to the treatment of HFpEF.

Prognostic impacts of changes in left ventricular ejection fraction in heart failure patients with preserved left ventricular ejection fraction

Background

It has been reported that recovery of left ventricular ejection fraction (LVEF) is associated with better prognosis in heart failure (HF) patients with reduced EF (rEF). However, change of LVEF has not yet been investigated in cases of HF with preserved EF (HFpEF).

Methods and results

Consecutive 1082 HFpEF patients, who had been admitted to hospital due to decompensated HF (EF >50% at the first LVEF assessment at discharge), were enrolled, and LVEF was reassessed within 6 months in the outpatient setting (second LVEF assessment). Among the HFpEF patients, LVEF of 758 patients remained above 50% (pEF group), 138 patients had LVEF of 40%–49% (midrange EF, mrEF group) and 186 patients had LVEF of less than 40% (rEF group). In the multivariable logistic regression analysis, younger age and presence of higher levels of troponin I were predictors of rEF (worsened HFpEF). In the Kaplan-Meier analysis, the cardiac event rate of the groups progressively increased from pEF, mrEF to rEF (log-rank, p<0.001), whereas all-cause mortality did not significantly differ among the groups. In the multivariable Cox proportional hazard analysis, rEF (vs pEF) was not a predictor of all-cause mortality, but an independent predictor of increased cardiac event rates (HR 1.424, 95% CI 1.020 to 1.861, p=0.039).

Conclusion

An initial assessment of LVEF and LVEF changes are important for deciding treatment and predicting prognosis in HFpEF patients. In addition, several confounding factors are associated with LVEF changes in worsened HFpEF patients.

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.

Sleep Disordered Breathing and Cardiovascular Diseases

Sleep disordered breathing (SDB), which causes sleep deprivation, intermittent hypoxia, and negative intrathoracic pressure swings, can be accompanied by other harmful pathophysiologies relating to cardiovascular diseases (CVD), including sudden death, atrial fibrillation, stroke, and coronary artery disease leading to heart failure. Continuous positive airway pressure (CPAP) therapy for SDB has been reported to provide favorable effects such as lowered systemic blood pressure and improved endothelial function. However, in recent randomized controlled trials, CPAP has failed to demonstrate its beneficial prognostic impact on the primary or secondary setting of CVD. In this review article, we describe the characteristics of SDB complicated with CVD, the prognostic impacts of SDB in CVD, and the beneficial effects of CPAP on CVD.

Association between sleep-disordered breathing and arterial stiffness in heart failure patients with reduced or preserved ejection fraction

AIMS

Sleep-disordered breathing (SDB) is associated with arterial stiffness, which may be one of the factors that lead to heart failure (HF). We examined the relationship between pulse wave velocity (PWV) and SDB in patients who have HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF).

METHODS AND RESULTS

We measured the apnoea-hypopnoea index (AHI) by polysomnography, echocardiographic parameters, and PWV in 221 HF patients. Age, blood pressure, and PWV were higher in HFpEF (ejection fraction > 50%, n = 70) patients than in HFrEF (ejection fraction < 50%, n = 151) patients. All HF patients were divided into three groups according to AHI: none-to-mild SDB group (AHI < 15 times/h, n = 77), moderate SDB group (15 < AHI < 30 times/h, n = 59), and severe SDB group (AHI > 30 times/h, n = 85). Although blood pressure and echocardiographic parameters did not differ among the three groups, PWV was significantly higher in the severe SDB group than in the none-to-mild and moderate SDB groups (P = 0.002). When the HFrEF and HFpEF patients were analysed separately, PWV was significantly higher in the severe SDB group than in the none-to-mild and moderate SDB groups in patients with HFpEF (P = 0.002), but not in those with HFrEF (P = 0.068). In the multiple regression analysis to determine PWV, the presence of severe SDB was found to be an independent predictor of high PWV in HFpEF (β = 0.234, P = 0.005), but not in HFrEF patients.

CONCLUSIONS

Severe SDB is associated with elevated arterial stiffness and may be related to the pathophysiology of HF, especially in HFpEF patients.

Current Perspectives on Systemic Hypertension in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a prevalent but incompletely understood syndrome. Traditional models of HFpEF pathophysiology revolve around systemic HTN and other causes of increased left ventricular afterload leading to left ventricular hypertrophy (LVH) and diastolic dysfunction. However, emerging models attribute the development of HFpEF to systemic proinflammatory changes secondary to common comorbidities which include HTN. Alterations in passive ventricular stiffness, ventricular-arterial coupling, peripheral microvascular function, systolic reserve, and chronotropic response occur. As a result, HFpEF is heterogeneous in nature, making it difficult to prescribe uniform therapies to all patients. Nonetheless, treating systemic HTN remains a cornerstone of HFpEF management. Antihypertensive therapies have been linked to LVH regression and improvement in diastolic dysfunction. However, to date, no therapies have definitive mortality benefit in HFpEF. Non-pharmacologic management for HTN, including dietary modification, exercise, and treating sleep disordered breathing, may provide some morbidity benefit in the HFpEF population. Future research is need to identify effective treatments, perhaps in more specific subgroups, and focus may need to shift from reducing mortality to improving exercise capacity and symptoms. Tailoring antihypertensive therapies to specific phenotypes of HFpEF may be an important component of this strategy.

Sleep disordered breathing in older adults with heart failure with preserved ejection fraction

Heart failure in older adults is frequently accompanied by sleep disordered breathing (SDB). Treatment of SDB in persons with heart failure with preserved ejection fraction (HFpEF) is unclear because most data is on heart failure with reduced ejection fraction (HFrEF). The purpose of this paper was to evaluate studies that report on the effects of positive airway pressure on patient outcomes in older adults with HFpEF and comorbid SDB. A search of the literature found six data-based studies (N = 36 to 126). Treatment with positive airway pressure reduced nighttime SDB symptoms and improved daytime functional status in persons with HFPEF and SDB (New York Heart Association Functional Class: effect sizes = -0.67 to -1.60). Limitations (i.e. only two studies were randomized controlled trials, small sample sizes, and women were under-represented) suggest that additional evidence is needed to guide treatment of SDB in older adults with HFpEF.

Heart failure and sleep disordered breathing

Sleep-disordered breathing (SDB) is frequently observed in patients with heart failure (HF), and complex pathologic conditions exist between both conditions. In this review article, we describe the characteristics of SDB complicated with HF, the prognostic impact of SDB in HF patients, and the favorable effects of positive airway pressure in HF patients with SDB.

Cardiovascular Outcomes With Minute Ventilation-Targeted Adaptive Servo-Ventilation Therapy in Heart Failure: The CAT-HF Trial

BACKGROUND

Sleep apnea is common in hospitalized heart failure (HF) patients and is associated with increased morbidity and mortality.

OBJECTIVES

The CAT-HF (Cardiovascular Improvements With MV-ASV Therapy in Heart Failure) trial investigated whether minute ventilation (MV) adaptive servo-ventilation (ASV) improved cardiovascular outcomes in hospitalized HF patients with moderate-to-severe sleep apnea.

METHODS

Eligible patients hospitalized with HF and moderate-to-severe sleep apnea were randomized to ASV plus optimized medical therapy (OMT) or OMT alone (control). The primary endpoint was a composite global rank score (hierarchy of death, cardiovascular hospitalizations, and percent changes in 6-min walk distance) at 6 months.

RESULTS

126 of 215 planned patients were randomized; enrollment was stopped early following release of the SERVE-HF (Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure) trial results. Average device usage was 2.7 h/night. Mean number of events measured by the apnea-hypopnea index decreased from 35.7/h to 2.1/h at 6 months in the ASV group versus 35.1/h to 19.0/h in the control group (p < 0.0001). The primary endpoint did not differ significantly between the ASV and control groups (p = 0.92 Wilcoxon). Changes in composite endpoint components were not significantly different between ASV and control. There was no significant interaction between treatment and ejection fraction (p = 0.10 Cox model); however, pre-specified subgroup analysis suggested a positive effect of ASV in patients with HF with preserved ejection fraction (p = 0.036).

CONCLUSIONS

In hospitalized HF patients with moderate-to-severe sleep apnea, adding ASV to OMT did not improve 6-month cardiovascular outcomes. Study power was limited for detection of safety signals and identifying differential effects of ASV in patients with HF with preserved ejection fraction, but additional studies are warranted in this population. (Cardiovascular Improvements With MV ASV Therapy in Heart Failure [CAT-HF]; NCT01953874).

Management of Sleep Apnea Syndromes in Heart Failure

Central sleep apnea (CSA) and obstructive sleep apnea (OSA) are prevalent in heart failure (HF) and associated with a worse prognosis. Nocturnal oxygen therapy may decrease CSA events, sympathetic tone, and improve left ventricular ejection fraction, although mortality benefit is unknown. Although treatment of OSA in patients with HF is recommended, therapy for CSA remains controversial. Continuous positive airway pressure use in HF-CSA may improve respiratory events, hemodynamics, and exercise capacity, but not mortality. Adaptive servo ventilation is contraindicated in patients with symptomatic HF with predominant central sleep-disordered events. The role of phrenic nerve stimulation in CSA therapy is promising.