Open Access Open Badges Study protocol

Determining the prevalence and predictors of sleep disordered breathing in patients with chronic heart failure: rationale and design of the SCHLA-HF registry

Holger Woehrle12, Olaf Oldenburg3, Michael Arzt48*, Andrea Graml2, Erland Erdmann5, Helmut Teschler6, Karl Wegscheider7 and the SCHLA-HF Investigators

Author Affiliations

1 Sleep and Ventilation Center Blaubeuren, Respiratory Center Ulm, Ulm, Germany

2 ResMed Science Center, Martinsried, Germany

3 Department of Cardiology, Heart and Diabetes Center North Rhine-Westphalia, Bad Oeynhausen, Germany

4 Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany

5 Clinic III for Internal Medicine, Heart Center University Hospital Cologne, Cologne, Germany

6 Department of Pneumology, Respiratory and Sleep Medicine, Ruhrlandklinik, University Clinic Essen, Essen, Germany

7 Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

8 Schlafmedizinisches Zentrum, Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany

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BMC Cardiovascular Disorders 2014, 14:46  doi:10.1186/1471-2261-14-46

Published: 9 April 2014



The objective of the SCHLA-HF registry is to investigate the prevalence of sleep-disordered breathing (SDB) in patients with chronic heart failure with reduced left ventricular systolic function (HF-REF) and to determine predictors of SDB in such patients.


Cardiologists in private practices and in hospitals in Germany are asked to document patients with HF-REF into the prospective SCHLA-HF registry if they meet predefined inclusion and exclusion criteria. Screening was started in October 2007 and enrolment was completed at the end of May 2013. After enrolment in the registry, patients are screened for SDB. SDB screening is mainly undertaken using the validated 2-channel ApneaLink™ device (nasal flow and pulse oximetry; ResMed Ltd., Sydney, Australia). Patients with a significant number of apneas and hypopneas per hour recording time (AHI ≥15/h) and/or clinical symptoms suspicious of SDB will be referred to a cooperating sleep clinic for an attended in-lab polysomnography with certified scoring where the definite diagnosis and, if applicable, the differentiation between obstructive and central sleep apnea will be made. Suggested treatment will be documented.


Registries play an important role in facilitating advances in the understanding and management of cardiovascular disease. The SCHLA-HF registry will provide consistent data on a large group of patients with HF-REF that will help to answer questions on the prevalence, risk factors, gender differences and stability of SDB in these patients by cross-sectional analyses. Further insight into the development of SDB will be gained by extension of the registry to include longitudinal data.

Registry; Prevalence; Heart failure; Sleep-disordered breathing; Obstructive sleep apnea; Central sleep apnea; Cheyne-Stokes respiration; Predictors