From the Guidelines
Central sleep apnea (CSA) is a sleep disorder characterized by pauses in breathing during sleep due to a lack of effort to breathe, rather than a physical blockage in the airways.
Definition and Causes
- CSA is often associated with underlying medical conditions, such as heart failure with reduced ejection fraction (HFrEF) 1.
- In the context of HFrEF, CSA can manifest as a compensatory mechanism to offset the adverse effects of the condition, similar to the effects of continuous positive airway pressure (CPAP) 1.
Clinical Significance
- Persistent CSA, despite optimal guideline-directed therapies, is a marker of persistent heart failure 1.
- The unique characteristics of CSA provide a natural compensatory mechanism, highlighting the complexity of the relationship between CSA and underlying medical conditions 1.
From the Research
Definition of Central Sleep Apnea (CSA)
- Central sleep apnea (CSA) is characterized by recurrent apnoeas during sleep with no associated respiratory effort 2, 3, 4, 5.
- It is defined as a group of conditions in which cessations in air flow occur without respiratory effort 5.
Pathophysiology of CSA
- CSA mostly results from withdrawal of the wakefulness drive in sleep leaving ventilation under metabolic control 2.
- The pathophysiology of CSA varies greatly, with unstable ventilatory control during sleep being the hallmark of CSA 3.
- Factors contributing to the cessation of air flow during sleep include the concept of the apnea threshold and the loss of the wakefulness drive to breathe 5.
Types and Causes of CSA
- CSA encompasses a diverse group of conditions with differing aetiologies and pathophysiology, including idiopathic (primary) CSA, Cheyne-Stokes breathing, and high altitude-induced periodic breathing 2, 3.
- CSA can be secondary to various medical conditions, high altitude, and medication exposure, and can also emerge during obstructive sleep apnea therapy 4.
Treatment of CSA
- Treatment of CSA varies according to underlying aetiology and can include positive airway pressure, adaptive servo ventilation, non-invasive ventilation, and optimization of medical therapy 2, 6, 5.
- The choice of treatment depends on the typology of respiratory disturbances observed by polysomnography, changes in blood gases, and ventilatory control 6.