Effect of adaptive servo-ventilation for central sleep apnoea in systolic heart failure on muscle sympathetic nerve activity: a SERVE-HF randomised ancillary study

Clinical advantages of reduced expiratory positive airway pressure setting in adaptive servo-ventilation therapy

The clinical ramifications of adaptive servo-ventilation (ASV) therapy have stirred debate within the medical community. Given the potential detrimental effect of elevated expiratory positive airway pressure (EPAP) on cardiac output, we hypothesized that relatively lower EPAP may be recommended for successful ASV therapy. In-hospital patients with congestive heart failure refractory to medical therapy were included in the prospective cohort study of ASV therapy on prognosis in repeatedly hospitalized patients with chronic heart failure: longitudinal observational study of effects on readmission and mortality (SAVIOR-L) study. Assignment to either the ASV treatment group or the medical management group was at the discretion of the attending physicians. For the purposes of this retrospective study, our focus remained solely on the ASV cohort. We conducted an extensive analysis to elucidate the influence of lower EPAP settings on midterm mortality. A total of 108 patients were included. The median age was 74 years, and 83 (77%) patients were male. The median EPAP setting employed was 4 cmH2O, with 60 patients subjected to EPAP levels below 5 cmH2O. There were no significant differences in the baseline characteristics between the lower and higher EPAP groups, which were divided at the EPAP cutoff of 4.5 cmH2O (p > 0.05 for all). A trend toward reduced mortality emerged among patients with EPAP settings below 5 cmH2O, exhibiting a hazard ratio of 0.48 (95% confidence interval 0.22-1.07, p = 0.072) after adjusting for potential confounding factors: 2-year mortality 26% vs. 38%; p = 0.095. Heart failure readmission rates were not significantly different between the two groups (p = 0.61). The adoption of relatively lower EPAP settings during ASV therapy may be advisable. Such an approach has the potential to ameliorate mortality rates while concurrently maintaining heart failure recurrence rates at levels commensurate with those with default EPAP settings.

Comparative effectiveness of therapies for sleep-disordered breathing in heart failure patients: A comprehensive systematic review and network meta-analysis

BACKGROUND

The prevalence of sleep-disordered breathing (SDB) in patients with heart failure (HF) is a significant concern, leading to adverse outcomes. This network meta-analysis (NMA) is dedicated to evaluate the relative effectiveness of diverse therapeutic approaches for SDB treatments in the context of HF.

METHODS

An extensive search up to May 19, 2023, was implemented in PubMed, Cochrane, Embase, and Web of Science to identify randomized controlled trials (RCTs). These trials compared adaptive servo ventilation (ASV), automatic positive airway pressure (APAP), Bi-level positive pressure ventilation (Bi-level PPV), continuous positive airway pressure (CPAP), and oxygen therapy against placebo or standard treatment. Key outcomes included cardiac function indicators (left ventricular ejection fraction [LVEF], plasma B-type natriuretic peptide [BNP] levels), polysomnography data (apnea-hypopnea index [AHI], Mean and Minimum Oxygen Saturation), and patient-reported quality of life measures (Epworth sleepiness scale [ESS]). A random-effects Bayesian NMA was utilized to evaluate and compare the efficacy of these interventions.

RESULTS

The study revealed significant therapeutic effects of different interventions in sleep apnea patients. For patients with obstructive sleep apnea (OSA), CPAP demonstrated superior efficacy in enhancing average oxygen saturation (mean difference (MD) = 0.98; 95 % credible interval (CI) [0.07,2.09]), improving LVEF (MD = 5.66; 95 % CI [0.71, 10.08]), and reducing AHI (MD = -20.61; 95 % CI [-33.84, -9.9]). In the case of central sleep apnea (CSA), the therapeutic approaches showed varying degrees of effectiveness. CPAP proved most effective for enhancing average oxygen saturation(MD = 1.1; 95 % CI [0.26,1.98]). ASV was the most effective in lowering AHI (MD = -32.11; 95 % CI [-47.5, -17.16]), increasing lowest oxygen saturation (MD = 8.14; 95 % CI [1.72,14.92]), and enhancing LVEF (MD = 6.58; 95 % CI [0.06,12.49]).

CONCLUSION

No single SDB treatment uniformly benefits all clinical indicators in SDB and HF patients.

Sleep-disordered breathing and heart failure: a vicious cycle of cardiovascular risk

Sleep-disordered breathing (SDB) represents an important cardiovascular risk factor that is still often underestimated and not always optimally treated. Such breathing disorders can induce several harmful effects on the heart, also favoring the development of arrhythmias, ischemic heart disease, and left ventricular remodeling. Obstructive sleep apnea syndrome (OSA) is more frequent in heart failure patients than in the general population, promoting the worsening of left ventricular dysfunction. Both sleep apnea and heart failure have common clinical manifestations but also similar neurohormonal characteristics, contributing to the development and progression of heart failure and resulting in increased mortality. The pathophysiological mechanisms underlying left ventricular dysfunction associated with SDB will be analyzed, and the potential therapeutic effects of gliflozins on OSA in heart failure patients will be discussed.