Cardiovascular physiology
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.)
o
Stroke volume (= end-diastolic volume - end-systolic volume)
o
Ejection fraction (= stroke volume / end-diastolic volume)
o
((Cardiac Output)) is mathematically ` to ((Systole))
·
o
Inotropic, chronotropic, and dromotropic states
·
o
Cardiac input (= heart rate * suction volume Can be calculated by inverting terms in
Fick principle
•
o
Suction volume (= end-systolic volume + end-diastolic volume)
o
Injection fraction (=suction volume / end-systolic volume)
o
Cardiac input is mathematically ` to (Diastole))
Electrical conduction system of the heart
o
Electrocardiogram
o
Cardiac marker
o
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
o
Renin
o
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
o
Pulse pressure (systolic pressure - diastolic pressure)
o
Mean arterial pressure (usually approximated with diastolic pressure + 1/3 pulse
pressure)
o
Central venous pressure
Regional circulation
Name of
% of cardiac
circulation
output
Autoregulation Perfusion
Comments
pulmonary
100%
Vasoconstriction in response to
circulation
(deoxygenated)
hypoxia
cerebral
circulation
Fixed volume means intolerance of
[2]
15%
high
under-perfused high pressure. Minimal ability to use
anaerobic respiration
Minimal ability to use anaerobic
respiration. Blood flow through the left
coronary
circulation
5%
high
under-perfused
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
hepatic
circulation
renal
circulation
15%
low
Flow increases during digestion.
Part of portal venous system, so
15%
25%
oncotic pressure is very low
high
over-perfused
skeletal
muscular
Perfusion increases dramatically
17%[3]
during exercise.
circulation
cutaneous
circulation
Maintains glomerular filtration rate
Crucial in thermoregulation.
[4]
2%
over-perfused
Significant ability to use anaerobic
respiration
v?d?e
Cardiovascular system, physiology: cardiovascular physiology
Heart
Volumes Stroke volume = End-diastolic volume - End-systolic
volume
Cardiac output = Heart rate * Stroke volume
Afterload · Preload
Frank-Starling law of the heart · Cardiac function
curve · Venous return curve
Aortic valve area calculation · Ejection
fraction · Cardiac index
Interaction diagrams
Cardiac cycle · Wiggers diagram · Pressure volume
diagram
Chronotropic (Heart rate) · Dromotropic (Conduction
Tropism velocity) · Inotropic (Contractility) · Batmotropic
(Excitability) · Lusitropic (Relaxation)
Conduction system /
Cardiac electrophysiology
Cardiac action potential (Atrial action potential,
Ventricular action potential) · Effective refractory
period · Pacemaker potential · QT interval
Other Ventricular remodeling
Blood flow
Compliance · Vascular resistance (Total peripheral
resistance) · Pulse · Perfusion
Pulse pressure (Systolic - Diastolic) · Mean arterial pressure
Central venous pressure/right atrial pressure → Right
ventricular pressure → Pulmonary artery pressure →
Hemodynamics
Blood pressure
Pulmonary wedge pressure/left atrial pressure → Left
ventricular pressure → Aortic pressure
Jugular venous pressure
Portal venous pressure
Baroreflex · Kinin-kallikrein system · Renin-angiotensin
Regulation of BP system · Vasoconstrictors/Vasodilators · Autoregulation
(Myogenic mechanism, Tubuloglomerular feedback)
(From: http://en.wikipedia.org/wiki/Cardiovascular_physiology)