Fig. 1.

Direct mechanical effects and loss of neuromuscular control mechanisms together contribute to the pathophysiology of central sleep apnoea (CSA). Several risk factors associated with CSA are not explained by these pathways (e.g., male gender, age). Sympathetic activation seems to be the only mechanism that may contribute to CSA in patients with normal echocardiographic findings. It is also the only mechanism that is shared by the three different heart conditions. HFrEF heart failure with reduced ejection fraction, HFpEF heart failure with preserved ejection fraction