Cardiovascular physiology

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.[1]

Although the different aspects of cardiovascular physiology are closely interrelated, the subject is still usually divided into several subtopics.

Heart

Regulation of blood pressure

Hemodynamics

Under most circumstances, the body attempts to maintain a steady mean arterial pressure.[2]

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:

Regional circulation

Name of circulation% of cardiac outputAutoregulationPerfusionComments
pulmonary circulation100% (deoxygenated)Vasoconstriction in response to hypoxia
cerebral circulation15%[3]highunder-perfusedFixed volume means intolerance of high pressure. Minimal ability to use anaerobic respiration
coronary circulation5%highunder-perfusedMinimal 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 circulation15%lowFlow increases during digestion.
hepatic circulation15%Part of portal venous system, so oncotic pressure is very low
renal circulation25%highover-perfusedMaintains glomerular filtration rate
skeletal muscular circulation17%[4]Perfusion increases dramatically during exercise.
cutaneous circulation2%[5]over-perfusedCrucial in thermoregulation. Significant ability to use anaerobic respiration

See also

References

  1. Overview Archived January 17, 2007, at the Wayback Machine at Medical College of Georgia
  2. "Regulation of Increased Blood Flow (Hyperemia) to Muscles During Exercise: A Hierarchy of Competing Physiological Needs".
  3. Nosek, Thomas M. Essentials of Human Physiology. Section 3/3ch11/s3c11_13
  4. Nosek, Thomas M. Essentials of Human Physiology. Section 3/3ch11/s3c11_2
  5. Nosek, Thomas M. Essentials of Human Physiology. Section 3/3ch11/s3c11_10
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