CARDIAC OUTPUT (CO)

SUMMARY

1. CO = Heart Rate (HR) x Stroke Volume (SV).

2. BP = CO x Systemic Vascular Resistance (SVR).

3. SV determined by: preload, contractility, after-load, HR.

4. Preload determined by: venous return to the heart; venous return = systemic filling pressure: CVP.

5. Myocardial contractility determined by: intrinsic factors (cardiac sympathetic stimulation), extrinsic factors (circulating catecholamines).

6. Afterload (ventricular wall tension that has to be generated in order to eject blood out of the ventricle, analogous to arterial pressure) determined by: SVR.

Reference(s)

Barrett, K.E., Barman, S.M., Brooks, H.L., X, J. and Ganong, W.F. (2019). Ganong’s review of medical physiology. 26th ed. New York: Mcgraw-Hill Education