Several factors contribute to Cheyne-Stokes
respiration, including hyperventilation from pulmonary
congestion and hypoxia; hyperventilation leads to
a low arterial co2 level, which triggers a central apnea
once the apneic threshold is reached. This cycle further
stresses the failing heart.14 In addition, patients with
heart failure have a prolonged circulation time, leading
to delays in transmitting changes in arterial blood gas
measurements to the carotid body chemoreceptors.
This circulatory delay influences the length of hyperpnea.
14 Cheyne-Stokes respiration is a marker of poor
prognosis in patients with heart failure, especially if it
occurs during the daytime.15
Fatigue and weakness are common but nonspecific
symptoms of heart failure. Severe heart failure may lead