Download The Heart - Blair Community Schools

4/25/16 Chapter 18 – The Heart
“Do
What do we already know?
you love me with all your
heart?”
“My heart doesn’t love you at
all. It’s a chunk of muscle that
pumps blood”
What is the heart?
•  If you had only one word to describe the
heart?
–  Pump
•  Two words?
–  Pumping Muscle
•  Three words?
–  Chambered Pumping Muscle
Big Idea: Function
•  Why does your heart pump??
Transport!
• 
• 
• 
• 
• 
• 
Nutrients
O2, CO2
Waste
Heat
Hormones
Immune Cells
But more on that LATER…
BI: Size & Shape (Gross Anatomy)
•  Size:
–  Double fist (adult) , fist (child)
BI: Location (Gross Anatomy)
•  Location:
–  Not where you put your hand
•  Mass:
–  250-350 grams (<1#)
•  Shape:
–  Cone shaped (heart shaped!)
1 4/25/16 Location
• 
• 
• 
• 
• 
• 
• 
• 
• 
Medial anterior portion of chest
5 in long
Between 2nd-5th ribs
Behind the sternum
Between the lungs
Base à R shoulder
Apex à L Hip
Sits on diaphragm
Point of Maximal Intensity
–  Apex contacts chest wall
–  Can best feel heartbeat
–  Around left nipple
Location
• 
• 
• 
• 
• 
• 
• 
• 
• 
Medial anterior portion of chest
5 in long
Between 2nd-5th ribs
Behind the sternum
Between the lungs
Base à R shoulder
Apex à L Hip
Sits on diaphragm
Point of Maximal Intensity
–  Apex contacts chest wall
–  Can best feel heartbeat
–  Around left nipple
Location
•  Mediastinum Cavity
BI: Coverings (Gross Anatomy)
Pericardium
•  Think back!!
•  Peri=
•  Cardi =
•  Double-walled sac
•  Keeps things
friction-free
Coverings
Pericardium
•  Double-walled sac
•  Keeps things friction -free
Ø  Fibrous Pericardium
attaches & anchors
Ø  Serous Pericardium
slippery liner
Coverings
Pericardium
•  Double-walled sac
•  Keeps things friction -free
Ø  Fibrous Pericardium
attaches & anchors
Ø  Serous Pericardium
slippery liner
•  Parietal Layer (Serous)
lines fibrous pericardium
•  Parietal Layer (Serous)
lines fibrous pericardium
•  Pericardial Cavity
serous fluid
•  Pericardial Cavity
serous fluid
•  Visceral Layer (Serous)
lines outside of heart
= pericardium
•  Visceral Layer (Serous)
lines outside of heart
= pericardium
Peri = around Cardi = heart
2 4/25/16 BI: Heart Wall (Gross Anatomy)
Ø  Epicardium Epi = upon; Cardi = heart
•  = visceral pericardium!
Ø  Myocardium Myo = muscle
•  What kind of muscle??
•  Bulk of heart
•  Bundles of muscle are
arranged in spiral and
circular patterns
Review / Draw It
Pericardium Ø  Fibrous Pericardium
Ø  Serous Pericardium •  Parietal Layer
Ø  Epicardium
Heart Wall Ø  Myocardium
Ø  Endocardium
•  Pericardial Cavity
•  Visceral Layer
Ø  Endocardium Endo = inside
•  Squamous Epithelial & Connective Tissue
•  Lines
•  All heart chambers
•  Continuous with lining of all veins/arteries coming
in and out of the heart
…Review…
•  What cavity is the heart located in?
–  Mediastinum
•  What is the covering of the heart called?
–  Pericardium
•  What are the three layers/components of
the visceral serous pericardium?
…Review…
•  What layer of the pericardium functions
to attach and anchor?
–  Fibrous Pericardium
•  What is the point of maximal intensity
and where is it located?
–  Parietal Layer, Pericardial Cavity, Visceral
Layer
What is the heart?
•  A blood-pumping muscle
–  How does a garden waterfall work?
•  A pump creates pressure to move the
water
–  How does a hair spray can work?
•  Fluids move from high pressure to low
pressure
The Heart
•  The heart creates and maintains a
pressure gradient
–  High hydrostatic pressure to move blood out
of the heart
–  Low hydrostatic pressure to allow blood into
the heart
•  Chambers, valves, veins and arteries
all work together to create and
maintain the pressure gradient
3 4/25/16 Big Idea: Internal Heart Structure
Internal Heart Structure
•  Heart chambers are
separated by 4 valves
•  Divided into 2 parts
by an inner septum
•  4 chambers
•  Atrium = top 2
–  Mitral (bicuspid)
•  L At / L Vt
–  Tricuspid
–  Low pressure
–  Thin walls
–  Receiving chambers
•  R At / R Vt
–  Pulmonary Semilunar
•  R Vt / Pulmonary Artery
•  Ventricle = bottom 2
–  Aortic semilunar
–  High pressure
–  Thick walls
–  Discharging chambers
Valves
•  Allow blood to enter but not exit chambers
Ø  Atrioventricular Valves
Mitral & Tricusupid
Ø  Semilunar Valves
Pulmonary & Aortic
Semilunar Valves
Ø  Aortic Semilunar & Pulmonary Semilunar
•  Guard bases of the aorta and pulmonary trunk
•  Prevent backflow
•  Three cusps that look like crescent moons
•  L Vt / Aorta
Atrioventricular Valves
Ø  Tricuspid Valve
•  Right side
•  Three cusps
Ø  Mitral (Bicuspid) Valve
•  Left side
•  Two cusps
Ø  Cusp
•  Flaps of endocardium
reinforced by connective
tissue
Ø  Chordae Tendineae
•  “heart strings”
•  Anchor cusps to the papillary
muscles
Valves
Ø “Lub” = closure of mitral & tricuspid valves
Ø “Dub” = closure of aortic & pulmonary
semilunar valves
4 4/25/16 Valves: All About the Pressure
•  “Lub” = closure of mitral & tricuspid valves
–  Close to build up pressure when ventricles contract
to pump blood out of the heart
–  Systole = high pressure caused by ventricle
contraction
Valves: All About the Pressure
•  “Dub” = closure of aortic & pulmonary semilunar
valves
–  Close at the start of diastole
–  Diastole = ventricles relaxing to receive next gush
of blood from the L & R atria
Valves
Ø  Note
•  No valves guard entrances from vena cava or
pulmonary veins
Which brings us to…
The Internal Heart
Internal Heart Structure: Details
•  Interatrial Septum
–  Fossa Ovalis Location of fetal
heart foramen
ovale
Internal Heart Structure: Details
•  Ventricles
–  Trabeculae Carneae: Irregular ridges of muscle
–  Papillary Muscles: Valve function, attach to chordae tendineae
–  Massive Myocardium
•  Right Atrium
Pectin = comb
–  Pectinate Muscles
•  Found on anterior
wall
•  Posterior wall is
smooth
•  No distinguishing
features in L At
5 4/25/16 Big Idea: Blood Movement
1.  Right Ventricle
2.  Pulmonary Semilunar
Valve
3.  Pulmonary Trunk
4.  R/L Pulmonary Arteries*
5.  R/L Lungs
6.  Lung Capillaries
7.  Pulmonary Veins*
8.  Left Atrium
<Contracts>
(creates pressure)
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
Right Ventricle
Pulmonary Semilunar Valve
Pulmonary Trunk
R/L Pulmonary Arteries*
R/L Lungs
Lung Capillaries
Pulmonary Veins*
Left Atrium
<Contracts>
(creates pressure)
Blood Movement: Systemic Circuit
1. 
Superior & Inferior
2. 
3. 
4. 
5. 
6. 
7. 
Aortic Semilunar Valve
Aorta*
Arteries
Capillaries
Veins
Vena Cava
8. 
Right Atrium
Superior & Inferior
8.  Right Atrium
<Contracts>
(creates pressure)
9.  Tricuspid Valve
10.  Right Ventricle
Left Ventricle
<Contracts>
(creates pressure)
Aortic Semilunar Valve
Aorta*
Arteries
Capillaries
Veins
Vena Cava
<Contracts>
(creates pressure)
*Aorta is about the size of a garden hose!
Largest artery in the body
Systemic & Pulmonary Circuits
•  Removes CO2 from the
blood and replenishes
O2
Systemic Circuit
1.  Left Ventricle
2. 
3. 
4. 
5. 
6. 
7. 
Ø  Carbaminohemoglobin
becomes oxyhemoglobin
<Relaxed>
(lower pressure)
*Pulmonary
arteries
are the
the only
only place
place you
you
*Pulmonary
veins are
willwill
find
deoxygenated
blood in
in aanvein
artery
find
oxygenated blood
<Contracts>
(creates pressure)
Ø  Right side of heart is the
pump
Ø  O2 needs to get where?
9.  Mitral Valve
10.  Left Ventricle
9.  Mitral Valve
10.  Left Ventricle
<Relaxed>
(lower pressure)
Pulmonary Circuit
Ø  Left side of heart is the
pump
Ø  High pressure circulation
Ø  5x more friction/resistance
to blood flow than
pulmonary circuit
Ø  Left ventricle wall 3x
thicker than right and has
larger chamber
9.  Tricuspid Valve
10.  Right Ventricle
Blood Movement: Details
•  Right atrium receives
•  Left atrium receives
blood from three veins:
blood from four
1.  Superior vena cava
pulmonary arteries
2.  Inferior vena cava
3.  Coronary Sinus…
6 4/25/16 Congestive Heart Failure
1. 
2. 
3. 
Left Ventricle
Aortic Semilunar Valve
Aorta*
•  LV can’t pump blood
out to body
•  It backs up and leaks
into the lungs
•  Eventually backs up
into the lungs
•  Lungs are “congested”
Big Idea: Coronary Circulation
•  Myocardium is too thick for blood diffusion
–  Coronary Arteries
–  Cardiac Veins
BUT WAIT…
Where does the
heart get blood??
Coronary Arteries
•  Right and left coronary arteries
–  Come from the base of the aorta
–  Encircle heart
–  Lie in coronary sulcus
Cardiac Veins
•  Cardiac Veins
–  Join together at coronary sinus
–  Empty into right atrium
Which brings us to…
The External Heart
7 4/25/16 Big Idea: External Anatomy
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R/L Atria
R/L Ventricles
R/L Coronary Sulcus
R/L Coronary Arteries
Coronary Sinus posterior
Pulmonary Trunk
R/L Pulmonary Arteries
Aortic Arch
External Anatomy
• 
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R/L Atria
R/L Ventricles
R/L Coronary Sulcus
R/L Coronary Arteries
Coronary Sinus posterior
Pulmonary Trunk
R/L Pulmonary Arteries
Aortic Arch
–  Brachiocephalic
–  Left common carotid
–  Left subclavian
–  Brachiocephalic
–  Left common carotid
–  Left subclavian
•  Pulmonary Arteries
•  Sup/Inf Vena Cava
•  Pulmonary Arteries
•  Sup/Inf Vena Cava
Coronary Sinus
• 
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• 
R/L Atria
R/L Ventricles
R/L Coronary Sulcus
R/L Coronary Arteries
Coronary Sinus posterior
Pulmonary Trunk
R/L Pulmonary Arteries
Aortic Arch
External Anatomy
•  Auricles “Little Ears”
–  Small appendages that slightly increase atrial volume
–  Brachiocephalic
–  Left common carotid
–  Left subclavian
•  Pulmonary Arteries
•  Sup/Inf Vena Cava
That was all gross anatomy.
Now we move on to
Microscopic
Anatomy
Think
CELLULAR!
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