Transcript Introduction: Basic Anatomy of the Heart

Neat Fact – Your heart beats about 100,000 times in one day and about 35 million times in a
year. During an average lifetime, the human heart will beat more than 2.5 billion times.
Introduction: Basic
Anatomy of the Heart
Chapter Learning Objectives:
1) Describe the location, approximate size, and
function of the heart
2) Describe the protective coverings of the heart
3) Identify the major anatomical structures of the
heart and explain how they function
4) Trace the pathway of blood through the heart
5) Describe cardiac muscle
6) Explain the heart’s pacemaker and the electrical
conductivity of the heart
7) Explain the waves of an ECG
Developed by Stephanie Lanoue for L.I.T. 5/14/2007
Where is Your Heart Located?
Try this:
1)Stand up.
2)Put your hand on your heart (keep it there).
Neat Fact: The heart pumps about 1 million barrels of blood during an
average lifetime--that's enough to fill more than 3 super tankers.
PREDICT
How big is your heart?
Neat Fact: On average, your body has about 5 liters of blood
continually traveling through it by way of the circulatory system.
How Would You Describe
the Heart? What Do You
Already Know About It?
Class Activity: Appreciating Your Heart as a
Pump.
The Heart’s Protective
Coverings
▪ Do you know that the heart
has 2 protective membranes
around it?
Heart enclosed in double-walled sac called
the ________________.
Superficial – fibrous pericardium
Deep – serous pericardium
*between the 2 layers is some fluid
Remember the number…
Next, we are going to learn basic heart anatomy:
▪ 4 chambers
▪ 4 valves
▪ 4 main blood vessels coming into/ exiting the
heart
Orientation of the Heart in
the Body
Right
Right
LeftLeft
Remember, you are looking at someone else’s chest!
(Speaking of someone else’s chest…heart surgery photos)
Photos from Open Heart Surgery Observations –
Methodist Hospital, Houston, TX
Basic Heart Anatomy
NOTE TO STUDENTS: Label the structures of the heart on your
diagram as I explain them.
Heart Chambers
NOTE: Atria = plural form of atrium
Heart Anatomy Continued
Blood Vessels
Valves
1
2
3
semilunar valve image
(3 cusps are open)
Valves, flaps of connective tissue between
the atria and ventricles, allow blood to flow
one-way
mitral valve image
( 2 cusps)
Neat Fact: Heart sounds (“lub, dub”) are caused by the closing of the
heart valves. The mitral & tricuspid valves make the 1st sound, and the
Valves continued
Chordae tendineae (“heart strings”) attached to ______ and _____ valves.
They anchor valve cusps to the papillary muscles (which play a role in valv
function). Papillary muscles protrude from the ventricle walls.
REVIEW
12
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2
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3
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5
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6
What is a Heart Attack?
http://www.healthscout.com/animation/68/
13/main.html
Additional Important Arteries
Coronary circulation is blood provided by the right and left coronary arteries.
Left coronary
anterior interventricular artery (also
known as the left anterior descending
which supplies to the interventricular
septum and anterior walls of both
ventricles)
circumflex artery (supplies left atrium
and posterior walls of left ventricle).
Right coronary
marginal artery (supplies myocardium of
the lateral right side)
posterior interventricular artery
Cardiac Veins
After passing through capillary beds of the myocardium, the blood flows into the
coronary sinus (which empties blood into right atrium). Has 3 tributaries:
______ cardiac vein
______ cardiac vein
_______ cardiac vein
Also, several anterior cardiac veins.
Partner Activity: Blood Flow
Through the Heart
Instructions: Working with a partner, can you describe the
flow of blood through the heart? Start with the right atrium.
List all the major structures along the way (chambers,
valves, and vessels). Refer to the diagram on page 602.
Example: Rt. atrium > ? valve> ?
(chamber) > ? valve up the
pulmonary trunk which divides into
the > ? arteries (which send the
deoxygenated blood into the ? for
O2.) From the lungs back to the
heart along the ? Veins > ?
(chamber) through the ? Valve >?
(chamber) > ? Valve > Aorta > Body
> Venae cavae.
Cardiac Muscle
Cardiac muscle – _______, short (fat/ _______)
cells that are interconnected for quicker
communication & conduction of electrical current.
Video footage: http://video.aol.com/video-detail/beating-humanheart-cells-from-embryonic-stem-cells/4230805508
Conduction System
Know Sequence of Excitation:
1. Sinoatrial node (SAN) or __________ >
2. _______ventricular node (AVN) >
See animation:
http://www.jdaross.cwc.
net/cardiac_cycle.htm
3. Atrioventricular bundle (bundle of ___) >
4. Right and Left bundle branches >
5. Purkinje fibers (directly supply the papillary muscles)
Electrocardiogram (ECG)
http://www.cardioconnection.org/frameWork.aspx?cnt=cad/diagnosis/ecg#
3 Distinguishable
Waves:
___ – initiation of the
heartbeat in the atria
___ – movement of
the electrical current
through the ventricles
__ – recovery phase;
electrical current
spreads back over the
ventricles in the
Electrocardiogram (ECG) continued
Electrocardiogram (ECG)
Findings
Healthy heart – _____, ______, and timing of waves tend
to be _____________
Unhealthy heart – waves are ______
Examples: an enlarged R wave hints of enlarged
ventricles or a prolonged Q-T interval may reveal
ventricular arrhythmias
Normal and Abnormal
ECG Readings
(a) _______– steady sinus
rhythm
(b) Non-functional _____
(c) Heart _____ – damage to
the AVN (interferes with the
ventricles receiving pacing
impulses)
(d) __________ fibrillation
(acute heart attack or
electrical shock)
Normal and Abnormal ECG Readings
continued
Arrhythmias – ________ heartbeats caused by
uncoordinated atrial and ventricular contractions
Example: atrial flutter
http://www.youtube.com/watch?v=3q4TJUmMztY
___________ – rapid and irregular contractions; SAN
looses control of setting the pace; fatal condition
Other Heart Abnormalities
Heart ________ – blood back flowing through a
heart valve
___________ –abnormally fast heart rate
__________ – heart rate slower than 60 beats per
minute
Congestive heart failure – progressively worsening
condition in which the heart can no longer pump
blood efficiently (heart weakens and enlarges)