Physiology, Cardiac Output

Excerpt

Cardiac output (CO) is the amount of blood pumped by the heart minute and is the mechanism whereby blood flows around the body, especially providing blood flow to the brain and other vital organs. The body’s demand for oxygen changes, such as during exercise, and the cardiac output is altered by modulating both heart rate (HR) and stroke volume (SV). As a result, the regulation of cardiac output is subject to a complex mechanism involving the autonomic nervous system, endocrine, and paracrine signaling pathways.

Because every tissue in the body relies on the heart pumping blood for nourishment, any cardiovascular dysfunction has the potential to result in significant morbidity and mortality. Heart disease affects nearly 30 million Americans annually and is the number one cause of death in the United States. The degree of functional impairment can be assessed by a variety of methods that guides diagnosis, prognosis, and treatment. As a clinician, one will come across heart disease in the course of practice and should be familiar with the basics of cardiac function.