Download Heart PPT

Cardiovascular system
Structure of heart…what do I know?
http://www.softschools.com/science/human_body/hea
rt_cross_section/
Cardiovascular system
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Heart, blood vessels, and blood
Transports O2 and nutrients to body
cells
Transports CO2 and waste materials
away from the body cells
Heart
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muscular, hollow organ: “pump”
size of your fist
located in mediastinal cavity,
between the lungs, behind the
sternum and above the diaphragm
3 layers of tissue form the
heart
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endocardium:
smooth, inner layer
of heart and blood
vessels
myocardium: thickest
part; middle layer;
muscular and allows
for contraction of
heart
Pericardium
(epicardium): double
layered membrane or
sac that covers the
outside of the heart
septum
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muscular wall that
divides the heart
into right and left
sides
prevents blood
from moving
between right and
left sides of heart
Heart chambers: 4 major
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atria: 2 upper
chambers
right atria receives
unoxygenated
blood from body
left atria receives
oxygenated blood
from the lungs
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ventricles: 2 lower
chambers
right ventricle: receives
blood from right atrium
pushes the blood into the
pulmonary artery, which
carries the blood to the
lungs for oxygen
left ventricle: receives
oxygenated blood from
left atrium
pushes blood into aorta so
it can be carried to body
cells
valves
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one way valves in
chambers of the
heart keep the
blood flowing in the
right direction and
prevent it from
backing up
tricuspid valve
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located between
right atrium and
right ventricle
-closes when right
ventricle contracts
and pushes blood
to the lungs
-prevents blood
backflow into
right atrium
pulmonary valve
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located between the right
ventricle and pulmonary
artery (this blood vessel
carries blood to the
lungs)
-closes when the right
ventricle has finished
contracting and pushing
blood into the pulmonary
artery
-prevents blood from
flowing back into the
right ventricle
mitral valve
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located between the
left atrium and left
ventricle
-closes when left
ventricle is
contracting and
pushing blood into
the aorta so it can be
carried to the body
-prevents blood from
flowing back into left
atrium
aortic valve
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located between the
left ventricle and the
aorta (largest artery
in the body)
-closes when left
ventricle is finished
contracting and
pushing blood into
the aorta
-prevents blood from
flowing back into left
ventricle
Blood flow through heart
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Unoxygenated blood
received from inferior &
superior vena cava and
coronary sinus
Right atrium
Tricuspid valve
Right ventricle
Pulmonary or pulmonic
valve
Pulmonary trunk/Pulmonary
arteries ® and (L)
Lungs for CO2 and O2
exchange
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Left atrium
Mitral valve
Left ventricle
Aortic valve
Aorta
Oxygenated blood carried
to entire body
http://www.youtube.com/w
atch?v=q0s1MC1hcE&feature=related
http://www.youtube.com/w
atch?v=mH0QTWzU-xI
http://www.youtube.com/w
atch?v=H04d3rJCLCE
Electrical Conduction
pathway of the heart:
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heart beat is regulated by electrical
impulses
SA node
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impulse begins in SA
(sinoatrial node; normal
rate 60 – 100 BPM)
group of nerve cells
located in right atrium
“pacemaker” of the heart
sends out electrical
impulses that spread out
over muscles in the atria
electrical impulse causes
atria to contract and
push blood into ventricles
electrical impulse then
travels to AV
(atrioventricular) node
AV node
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group of cells located
between atria and
ventricles (normal
rate 40 – 60 BPM)
AV node sends
electrical impulse
through nerve fibers
in the septum called
the Bundle of His
Bundle of His
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nerve fibers in the
septum
divides into right
and left bundle
branches
Right and left bundle
branches
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pathways that
carry the electrical
impulse down
through the
ventricles
bundles continue
to subdivide into
network of nerve
fibers throughout
ventricles called
Perkinje fibers
Perkinje fibers
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final fibers on electrical
conduction pathway
(normal rate 20 – 40
BPM)
spread electrical impulses
to all of the muscle tissue
in the ventricles
ventricles then contract
http://www.nhlbi.nih.gov
/health/healthtopics/topics/hhw/electric
al.html
EKG or ECG
(electrocardiogram)
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electrical conduction pattern occurs
about every 0.8 seconds
EKG or ECG (electrocardiogram):
machine that monitors and records
electrical impulses in the heart; used
to detect abnormal heart activity or
disease
EKG
p, qrs, t waves
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p wave: Atrial
depolarization or
contraction
qrs complex:
ventricular
depolarization or
contraction
t wave: ventricular
relaxation
Cardiac cycle
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Conists of mechanical and electrical
conduction
Both must function properly for normal
cardiac output
Helpful resources

http://highered.mcgrawhill.com/sites/0073520713/student_vie
w0/a_p_exercises.html#
http://www.gwc.maricopa.edu/class/bi
o202/cyberheart/hartint0.htm
http://www.heartpoint.com/theheart.h
tml