- Figure 7
Effect of Central Apneas on Stroke Volume in a Patient with Heart Failure
FIG. 7: This Figure reports data in the same format from a patient in the same study[2] as the patient depicted in Figure 5, showing stroke volume, blood pressure, and Cheyne-Stokes respiration (CSR) in a patient with heart failure and CSA. In this case, stroke volume is rising, not falling during the CSA (the opposite of OSA), and during the ventilatory period the stroke volume falls.
The reason for that is probably because the negative intrathoracic pressure is being generated during the ventilatory period, not during the apnea, and so the result is exactly the opposite of that with an OSA. However the Figure also shows that blood pressure is falling during the central apnea and rising slightly during the ventilatory period, which does not synchronize with the stroke volume; the reason for that is not clear. Finally the lowest trace shows the recurrent falls in SaO2.
References
Yumino D, Kasai T, Kimmerly D, et al. Differing effects of obstructive and central sleep apneas on stroke volume in patients with heart failure. Am J Respir Crit Care Med. 2013;187:433–438.
