Transcript heart - Images

Heart Dissection
Internal Examination
Objectives
1. Complete an internal dissection of the heart.
A. Label different parts of the heart
B. Review the parts with a partner
2. Clean after the dissection
What do you need???
• Red dots and Green dots…
– Get APRONS and GOGGLES for everyone at your
table
• Blue dots and Yellow dots…
– Get a DISSECTION PAN
– Get a HEART
• You have 5 minutes to get the materials.
First Thing…
• You need to remove the percardium from the
heart.
– Remember, the pericardium is a mucous
membrane that surrounds the heart.
• Cut the top layer (pericardium) at the apex
• Peel the pericardium from the heart.
Second Thing…
• You need to trim the fat from the aorta,
pulmonary vein, pulmonary artery, and
superior vena cava.
• Do this carefully using the scalpel and scissors.
First Cut
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Locate the pulmonary artery
Put the scissors inside of it.
Cut through the front side of this vessel.
Continue cutting down the artery and down through
the muscular wall of the right ventricle.
– This line should be above and parallel to the
coronary artery.
• Stop cutting when you reach the end of the cavity of
the right ventricle.
Now you can see…
• At the beginning of the pulmonary artery…
– You can see the pulmonary semilunar valve
• Look inside of the right atrium
– In the upper left of the right ventricle
– Notice a flap of tissue made of 3 leaflets
• This is the tricuspid valve
• This is connected by a bunch of tendons called chordae
tendinaea
• The thicker portion attaching the tendons to the wall
are papillary muscles
Second Cut
• Find the superior vena cava…
– Cut from the superior vena cava straight down
about 3 centimeters
– This will cut into the right atrium, but DO NOT cut
into the right ventricle.
• Look through the right ventricle.
– This is the tricuspid valve.
Third Cut
• Find the aorta…
– Cut straight down through the aorta
– Slowly cut until you can see the aortic semilunar
valve
First Incision
• Locate the right atrium
– Feel the right side (remember this is the side with the
superior vena cava)
– Find the chamber of the right atrium (heart will depress
here)
– Slide your finger until you cannot feel the chamber
• Move away from the middle of the heart
– Cut just through the atrial wall
• DO NOT cut too far, just through the wall.
– Continue the cut through the right ventricle and into the
apex”
Second Incision
• Continue the first incision…
– Start at the apex
– Cut up the left side of the heart
– Cut through the wall, but DO NOT cut past the
wall
Identification
• Now you can identify…
– Myocardium
– Septum
– Chordae Tendinaea
– Papillary Muscle
– 4 chambers: Right Atrium, Left Atrium, Right
Ventricle, Left Ventricle
– 4 valves: Aortic semilunar, Pulmonary semilunar,
Mitral bicuspid, Tricuspid
Measurements
• Measure the thickness of the wall of the right
ventricle in centimeters.
– Write this measurement down on a sheet of paper
• Measure the thickness of the wall of the left
ventricle in centimeters.
– Write this measurement down on a sheet of paper
Blood Flow
• Can you track the blood through the
heart??????
– Test your partner to see if she/he knows the blood
flow pattern.
Clean-up
• Clean the scalpel, scissors, and any other tools
used in the soapy water.
• Dry the tools
• Place the tools back where they should be.
• You will lose half of the lab points if this is not
done.