Cardiovascular physiology is the study of the cardiovascular system, specifically addressing the physiology of the heart ("cardio") and blood vessels ("vascular").
These subjects are sometimes addressed separately, under the names cardiac physiology and circulatory physiology.
Although the different aspects of cardiovascular physiology are closely interrelated, the subject is still usually divided into several subtopics.
Main article: Cardiac physiology
Under most circumstances, the body attempts to maintain a steady mean arterial pressure.
When there is a major and immediate decrease (such as that due to hemorrhage or standing up), the body can increase the following:
In turn, this can have a significant impact upon several other variables:
|Name of circulation||% of cardiac output||Autoregulation||Perfusion||Comments|
|pulmonary circulation||100% (deoxygenated)||Vasoconstriction in response to hypoxia|
|cerebral circulation||15%||high||under-perfused||Fixed volume means intolerance of high pressure. Minimal ability to use anaerobic respiration|
|coronary circulation||5%||high||under-perfused||Minimal ability to use anaerobic respiration. Blood flow through the left coronary artery is at a maximum during diastole (in contrast to the rest of systemic circulation, which has a maximum blood flow during systole.)|
|splanchnic circulation||15%||low||Flow increases during digestion.|
|hepatic circulation||15%||Part of portal venous system, so oncotic pressure is very low|
|renal circulation||25%||high||over-perfused||Maintains glomerular filtration rate|
|skeletal muscular circulation||17%||Perfusion increases dramatically during exercise.|
|cutaneous circulation||2%||over-perfused||Crucial in thermoregulation. Significant ability to use anaerobic respiration|