Simonds, Anita K.

Abstract Aims The Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnoea by Adaptive Servo Ventilation in Patients with Heart Failure trial investigated the effects of adaptive servo-ventilation (ASV) (vs. control) on outcomes of 1325 patients with heart failure and reduced ejection fraction (HFrEF) and central sleep apnoea (CSA). The primary outcome (a composite of all-cause death or unplanned HF hospitalization) did not differ between the two groups. However, all-cause and cardiovascular (CV) mortality were higher in the ASV group. Circulating biomarkers may help in better ascertain patients' risk, and this is the first study applying a large set of circulating biomarkers in patients with both HFrEF and CSA. Methods and results Circulating protein-biomarkers (n = 276) ontologically involved in CV pathways, were studied in 749 (57% of the trial population) patients (biomarker substudy), to investigate their association with the study outcomes (primary outcome, CV death and all-cause death). The mean age was 69 ± 10 years, and > 90% were male. The groups (ASV vs. control and biomarker substudy vs. no biomarker) were well balanced. The “best” clinical prognostic model included male sex, systolic blood pressure < 120 mmHg, diabetes, loop diuretic, cardiac device, 6-min walking test distance, and N-terminal pro BNP as the strongest prognosticators. On top of the “best” clinical prognostic model, the biomarkers that significantly improved both the discrimination (c-index) and the net reclassification index (NRI) of the model were soluble suppression of tumorigenicity 2 for the primary outcome; neurogenic locus notch homolog protein 3 (Notch-3) for CV-death and all-cause death; and growth differentiation factor 15 (GDF-15) for all-cause death only. Conclusions We studied 276 circulating biomarkers in patients with HFrEF and central sleep apnoea; of these biomarkers, three added significant prognostic information on top of the best clinical model: soluble suppression of tumorigenicity 2 (primary outcome), Notch-3 (CV and all-cause death), and GDF-15 (all-cause death).

Abstract Aims The SERVE-HF trial investigated the impact of treating central sleep apnoea (CSA) with adaptive servo-ventilation (ASV) in patients with systolic heart failure. A preplanned substudy was conducted to provide insight into mechanistic changes underlying the observed effects of ASV, including assessment of changes in left ventricular function, ventricular remodelling, and cardiac, renal and inflammatory biomarkers. Methods and results In a subset of the 1325 randomised patients, echocardiography, cardiac magnetic resonance imaging (cMRI) and biomarker analysis were performed at baseline, and 3 and 12 months. In secondary analyses, data for patients with baseline and 12-month values were evaluated; 312 patients participated in the substudy. The primary endpoint, change in echocardiographically determined left ventricular ejection fraction from baseline to 12 months, did not differ significantly between the ASV and the control groups. There were also no significant between-group differences for changes in left ventricular dimensions, wall thickness, diastolic function or right ventricular dimensions and ejection fraction (echocardiography), and on cMRI (in small patient numbers). Plasma N-terminal pro B-type natriuretic peptide concentration decreased in both groups, and values were similar at 12 months. There were no significant between-group differences in changes in cardiac, renal and systemic inflammation biomarkers. Conclusion In patients with systolic heart failure and CSA, addition of ASV to guideline-based medical management had no statistically significant effect on cardiac structure and function, or on cardiac biomarkers, renal function and systemic inflammation over 12 months. The increased cardiovascular mortality reported in SERVE-HF may not be related to adverse remodelling or worsening heart failure.