mechanism of cardiogenic PND
Last reviewed 09/2021
The blood volume is usually at its greatest at 2 am when the pulmonary venous pressure may build up to high levels.
The reduced level of consciousness during sleep permits the pulmonary venous pressure to stay above the 25 mm Hg without the patient being aware of the developing dyspnoea.
Eventually the worsening dyspnoea awakens the patient from sleep.