Cardiovascular physiology

You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-525-6884

Cardiovascular physiology is the study of the circulatory system. More specifically, it addresses 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

See Heart#Physiology for more details

• Cardiac output (= heart rate * stroke volume. Can also be calculated with Fick principle.)
  • Stroke volume (= end-diastolic volume - end-systolic volume)
  • Ejection fraction (= stroke volume / end-diastolic volume)
  • Inotropic, chronotropic, and dromotropic states

• Electrical conduction system of the heart
  • Electrocardiogram
  • Cardiac pacemaker
  • Cardiac action potential

• Frank-Starling law of the heart
• Wiggers diagram
• Pressure volume diagram

Blood vessels

See Blood vessel#Physiology for more details

• Compliance
• Microcirculation
• Starling equation
• Fick's law of diffusion
• Poiseuille's law
• Skeletal-muscle pump

Regulation of blood pressure

• Baroreceptor
• Baroreflex
• Renin-angiotensin system
  • Renin
  • Angiotensin
• Juxtaglomerular apparatus
• Aortic body and carotid body
• Autoregulation

Hemodynamics

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:

• Heart rate
• Total peripheral resistance (primarily due to vasoconstriction of arteries)
• Inotropic state

In turn, this can have a significant impact upon several other variables:

• Stroke volume
• Cardiac output
• Pressure
  • Pulse pressure (systolic pressure - diastolic pressure)
  • Mean arterial pressure (usually approximated with diastolic pressure + 1/3 pulse pressure)
  • Central venous pressure

Regional circulation

Name of circulation	% of cardiac output	Autoregulation	Perfusion	Comments
pulmonary circulation	100% (deoxygenated)			Vasoconstriction in response to hypoxia
cerebral circulation	15%[2]	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 muscle circulation	17%[3]			Perfusion increases dramatically during exercise.
cutaneous circulation	2%[4]		over-perfused	Crucial in thermoregulation. Significant ability to use anaerobic respiration

v • d • e Cardiovascular system, physiology: cardiovascular physiology
Volumes	Preload - Afterload - End-systolic volume - End-diastolic volume - Frank-Starling law of the heart
Interactions	Cardiac output - Wiggers diagram - Pressure volume diagram
Tropism	Chronotropic - Dromotropic - Inotropic
Hemodynamics	Baroreflex - Kinin-kallikrein system - Renin-angiotensin system - Vasoconstrictors - Vasodilators - Compliance - Vascular resistance
Other	Electrical conduction system of the heart (Cardiac action potential)

References

1. ↑ Overview at Medical College of Georgia
2. ↑ Physiology at MCG 3/3ch11/s3c11_13
3. ↑ Physiology at MCG 3/3ch11/s3c11_2
4. ↑ Physiology at MCG 3/3ch11/s3c11_10

External links

• MeSH Cardiovascular+physiology
• www.cvphsysiology.com - Comprehensive explanation of basic cardiovascular concepts.

WikiDoc Help Menu Quick Start.. Get Started Here! How to Login How to Search Pages How to Start a New Page How to Edit a Page Cheat Sheet Editing basics Learning Basic Formatting How to make Links in WikiDoc & to External Sites How to Make Lists How to Ignoring Formatting Adding References or Footnotes to Articles Tracking Changes You Have Made How to Put an Article Into a Category When Multiple Topics Should Go To The Same Page (MI, Acute MI, AMI) Using Redirection Advanced editing How to Make Tables How to Insert Images and Other Media How to Add Video Help:How to Make Columns Web Colors How To Make Templates How to Move Pages Inserting Dynamic Dates and Times Inserting WikiDoc Statistics Editing the Table of Contents Communicating your edits Let others know what you changed: The importance of Edit Summaries Minor Edits Edit Conflicts Help Videos You Can Watch Getting Started Video

Acknowledgement and Attribution Regarding Sources of Content

Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .