Transcript The Heart - TeacherWeb

The Heart
Let’s Get to the Heart of the Matter…
The Heart
Test your knowledge…What makes you tick?
Heart Facts:
http://www.webmd.com/heart-disease/rmquiz-know-heart
Pumping Heart Animation: How the Heart
Works 3D Video
https://www.youtube.com/watch?v=oHMmtq
Kgs50
A Most Unusual Story!!!
1.
2.
3.
4.
5.
6.
7.
8.
Inferior vena cava
Right atrium
Superior vena cava
Coronary sinus
Fossa ovalis
Right ventricle
Tricuspid valve
Chordae tendineae
A Most Unusual Story!!!
9. Papillary muscles
10. Pulmonary semilunar valves
11. Pulmonary trunk aka pulmonary artery
12. Lungs
13. Aorta
14. Ligamentum arteriosum
15. Blood capillaries
16. Biconcave
A Most Unusual Story!!!
17. Hemoglobin
18. Oxygen
19. Pulmonary veins
20. Left atrium
21. bicuspid/ mitral valve
22. Left ventricle
23. Thicker
24. Aortic semilunar valve
A Most Unusual Story!!!
25. Aorta
26. Arterioles
27. Oxygen
28. Carbon dioxide
29. Metabolic waste
30. Venule
31. Vein
32. Valves
A Most Unusual Story!!!
33. Massaging
34. 60s (1 min)
35. 119 or 120
Path: aorta
arteries
arterioles
capillary bed (O2
& nutrients in, CO2 & wastes out)
capillaries
Arteries Supplying the Heart
The heart is also
surrounded by
some fat.
Sometimes a
person’s heart is
so covered that
you can barely
see the muscle.
If the coronary arteries become
occluded, doctors will coat the area with
an anticoagulant and an antibiotic and
insert a stent (metal tube). It keeps the
artery open. If they have to perform a
bypass, they will use a leg vein and a
plastic coated staple.
Veins Draining the Heart
Internal Anatomy of the Heart
• Add the parts that are not on your diagram
• Make a note as to where the veins and arteries are coming from and
where they are going to
• Underline the parts with oxygenated blood in red
• Underline the parts with deoxygenated blood in blue
• Remember, the pulmonary artery is carrying deoxygenated blood, so
underline it in blue and the pulmonary vein is carrying oxygenated blood,
so underline it in red
As soon as a baby’s 4chambered heart is
formed at 4 weeks in the
womb, beating begins
Ligamentum arteriosum
-remnant of ductus
arteriosus; fetal bypass
#2
Coronary Sinus
-veins that collect
blood from the
myocardium
Fossa Ovalis
-remnant of
the foramen
ovale; fetal
bypass #1
Valves ensure a
one-direction flow
of blood
Chordae Tendineae
Walls 2x
thicker
Another
View…
A Dissected Pig Heart
Electrical Conduction System of the Heart
• Remember the nerve anatomy?
Electrical Conduction System of the Heart
Sinoatrial Node;
Natural pacemaker;
creates action
potential on its own
Left bundle branch
Mass of connective tissue
Takes care of top half of left ventricle muscle
Takes care of bottom half of left ventricle muscle
Atrioventricular
Aka AV Bundle
Action potential reaches the very end of fibers all at
the same time = contraction
Page 6
Pacemakers
http://radiopaedia.org/articles/cardiac-conduction-devices
https://openi.nlm.nih.gov/detailedresult.php?img=PMC3232581_IPC-9-15-g001&req=4
Sinoatrail Node Action Potential
The Cardiac Cycle
• The cycle of mechanical events occurring within one heart beat
• 1 heart beat = 1 cycle = 2 atrial contractions with 2 ventricular contractions
• http://www.hybridmedicalanimation.com/work/animation/beating-heart-with-blood-flow/
• https://www.youtube.com/watch?v=jLTdgrhpDCg
• 1 Cycle lasts approximately 0.8 sec = HR 72 bpm
• Diastole = relaxation = 0.5 sec
• Systole = contraction = 0.3 sec
1. This the start
of ventricular
contractions
2. & 3.Both pulmonary
and aortic
2. & 3. Both
tricuspid and
bicuspid
5. Just a little
blood is left in the
atria that is then
forced down into
the ventricles as
the atria contract.
Only the atria are
contracting.
Ventricles are
relaxed.
3. Atria are relaxed
but are receiving
blood, ventricles are
also relaxed
4. As soon as AV valves open, blood flows down
into the ventricles without the atria contracting
Events Occurring During the Cardiac Cycle
4 Graphs in
one
True or False???
• False
• The portion of the brainstem which contains the cardiac control
center is the medulla.
• False
• In a single beat of the heart, the second is a dub type of sound.
• False
• Contraction of the ventricles forces blood into the aorta producing
the peak systolic blood pressure. (remember, systole = contraction)
• True
• Starling’s Law of the heart states that the heart rate will increase in
response to the stretching of the right atrial wall. (because it stretches
the SA node…mechanical stimulation)
True or False???
• True
• The second sound is caused by the closing of the semilunar valve. (1st sound
is the closing of the AV valves)
• True
• It is possible to increase the heart rate with increase flow of blood into the
right atrium because of stretching of the atrial wall which in turn stimulates
the SA node.
• False
• The neurotransmitter associated with the parasympathetic unit is
acetylcholine.
• False
• The neurotransmitter associated with the sympathetic unit is adrenaline.
True or False???
• True
• Sympathetic control of the heart rate is by way of cardiac nerves.
• True
• It is the sympathetic unit that increases heart rate and the force of
contraction.
• True
• Neural stimulation is the primary influence in the control of the heart rate.
(chemicals are secondary)
• True
• It is the parasympathetic unit by way of the vagus nerve that serves as the
cardiac inhibitor. (so you don’t have to think about breathing, heart beat)
True or False???
• False
• In the aortic arch and & carotid arteries are specialized receptors. They
are responsible for monitoring CO2 and blood pH. (That’s why if you push
too hard on the carotid arteries, you will pass out.)
• True
• In the above areas, it is the baroreceptors that are sensitive to extreme
changes in blood pressure.
• False
• The heart rate increases when body temperature decreases. This allows
the heart to “shiver” along with the skeletal muscles in order to generate
additional body heat. The heart does not “shiver” under normal
conditions. It may “shiver” under extreme conditions, ex. heart attacks
with 400 contractions/ minute of ventricular contractions.
Vocabulary (on your flashcards)
1. Angina pectoris- Chest pain due to coronary heart disease
2. Angioplasty- A procedure used to restore blood flow to an artery,
usually performed on people with coronary artery disease
3. Coronary bypass surgery- A surgical procedure that diverts blood
flow around a section of a blocked artery in the heart; It creates a new
pathway of blood flow to the heart
4. Myocardial infarction- The death of the myocardial muscle after
prolonged or repeated periods of diminished blood flow.
5. Murmurs- A type of abnormal heart sound usually due to defective
heart valves
6. Incompetent heart valve- The result of a heart valve that leaks
7. Digitalis- This is given to people who suffer from heart failure as it
slows & strengthens the contractions of the heart muscle
8. Endocarditis- Inflammation of the lining of the heart caused by a
bacterial infection. This affects the valves more severely than other areas
of the heart & can lead to formation of scar tissue, causing valves to be
incompetent
9. Rheumatic heart disease- This is caused by a streptococcal infection
& may cause inflamed valves, particularly affecting the bicuspid (mitral)
valve, which can become narrow & stiff or incompetent
10.Heart failure- The result of a progressive weakening of the heart
muscle (ventricles) & the failure of the heart to pump blood effectively
11. Nitroglycerin- This works on arteries AND veins; It causes dilation of
the veins and arteries throughout the body, resulting in a decreased
venous return to the heart; This is frequently given to people who suffer
from coronary artery disease; This dilates coronary blood vessels &
increases blood flow to the cardiac muscle
12. Congenital heart disease- The result of abnormal heart development;
An example of this disease is a septal defect, which is a hole in the
interventricular septum (the wall between the right and left sides of the
heart)
13. Pericarditis- Inflammation of the outer layers of the heart
14.Calcium channel blockers- These work on arteries, not veins; Because
the action potentials that produce cardiac muscle contractions depend in
part on the flow of particular ions into the cardiac muscle cells, these can be
used to control the force of the heart contraction & reduce arrhythmia,
tachycardia & hypertension
15. Artificial pacemaker- This provides an electrical stimulus to the heart at
a set frequency
16.Myocarditis- Inflammation of the musculature of the heart
17. Patent ductus arteriosus- (open) Blood flows from the aorta into the
pulmonary trunk & into the lungs under high pressure, which damages them
as a consequence of this condition
18.Hypertension- Abnormally high blood pressure; Known as the “Silent
Killer”
19.Beta-adrenergic blocking agents- These bind to receptors for
epinephrine & norepinephrine & prevent these substances from having their
normal effect
20.Anticoagulants- An example of this is aspirin. One aspirin a day
may benefit those who are likely to experience a coronary thrombosis
(clot)
21.Coronary thrombosis- This is the formation of a blood clot in a
coronary vessel
22.Heart valve replacement/ repair- Synthetic materials, such as
plastic or Dacron, are used to manufacture a type of artificial heart
structure when surgical intervention is called for
Regulation of the Heart
Chemoreceptors signal the
glossopharyngeal nerve; this
nerve goes back to the
medulla oblongata
After working out,
cardiac (sympathetic)
nerves slow down, but
also get help from the
vagus nerve to slow
down the heart.
When the medulla of the adrenal glands is
stimulated, it produces adrenaline.
Chemoreceptors for CO2 and pH are in the
carotid sinus
Baroreceptors
are for blood
pressure
The Cardiac
(Sympathetic)
nerve affects heart
rate when working
out as well as
ventricular
contractions
Regulation of the Heart
• Neural stimulation (via cardiac nerves) is primary (1°)…about 90%
• Chemicals are a “booster” to cardiac rate and intensity, ex. Caffeine,
epinephrine (a respiratory dilator), norepinephrine…about 10%
Electrocardiogram
• Electrocardiogram = tracing
- An EKG shows the heart's electrical activity as line tracings on paper.
• Electrocardiograph = machine
- An instrument used in the detection and diagnosis of heart abnormalities
that measures electrical potentials on the body surface and generates a
record of the electrical currents associated with heart muscle activity.
P = atrial
contractions
Repolarization = return
to negative, resting
membrane potential
Depolarization =
positive ions flow into
the cell and cause
contraction
T = repolarization
of ventricles
QRS Complex = results from depolarization
of ventricles & signals ventricular
contraction… repolarization of atria also
occurs
Sources
•
http://images.slideplayer.com/16/5234307/slides/slide_21.jpg
•
http://image.slidesharecdn.com/biol121-chp20-pp-fall10-101123164449-phpapp02/95/biol-121-chp-20-the-cardiovascular-system-the-heart-46638.jpg?cb=1408445302
•
https://www.studyblue.com/notes/note/n/chapter-20-heart--physiology/deck/14100542
•
http://www.cvphysiology.com/Heart%20Disease/HD002.htm
•
http://gtaccir.deviantart.com/
•
http://www.netanimations.net/Heart-beating-lungs-breathing-body-organ-animations.htm
•
http://themissionlsc.com/wp-content/uploads/2015/09/heart-anatomy-quizlet.jpg
•
https://openi.nlm.nih.gov/detailedresult.php?img=PMC3232581_IPC-9-15-g001&req=4
•
http://www.dictionary.com/browse/electrocardiograph
•
classes.midlandstech.edu
•
https://www.studyblue.com/notes/note/n/phys20008-cardiovascular-system/deck/14720878
•
courses.lumenlearning.com