Prospective, follow-up registry of heart failure patients with or without sleep-disordered breathing (SDB). To test the hypothesis that treatment of nocturnal central sleep apnea with Cheyne-Stokes respiration by adaptive servoventilation (ASV) improves symptoms, cardiac performance and event-free survival.

The study is intended to investigate therapeutic effects of adaptive servoventilation in patients with sleep-disordered breathing and chronic heart failure. These effects include short-/long-term effects on

• symptoms and quality of life
• physical and cardiac performance (6min walking test, cardiopulmonary exercise testing)
• echocardiographic parameters
• arrhythmias
• NT-proBNP
• Respiratory stability (blood gases, rebreathing test, VE/VCO2-slope in cardiopulmonary exercise testing)
• Compliance with ASV therapy
• Event free survival (death, heart transplantation, assist device implantation)

All of these data are also obtained in patients who basically meet the inclusion criteria but in whom sleep-disordered breathing was excluded by means of cardiorespiratory polygraphy or polysomnography and in patients with sleep-disordered breathing who do not undergo adaptive servoventilation for various reasons.

Inclusion Criteria:

• Stable heart failure NYHA ≥ II
• EF ≤ 45%
• without sleep-disordered breathing (apnea-hypopnea-index <5/h) and those with moderate to severe central sleep apnea (apnea-hypopnea index ≥ 15/h) with or without adaptive servoventilation therapy

Exclusion Criteria:

• Cardiac resynchronization or pacemaker implantation within the last 6 months
• Significant COPD with an forced expiratory one-second capacity relative to vital capacity (FEV1/VC)< 70% (GOLD III)
• Respiratory insufficiency requiring long-term oxygen therapy
• Daytime hypercapnia at rest (pCO2 > 45 mmHg)
• Current ventilation therapy
• Cardiac surgery, PCI, myocardial infarction, unstable angina, TIA or stroke within 12 weeks prior to randomization
• Acute myocarditis within 6 months prior to randomization
• Pregnancy

Patients of a university hospital