Heart Anatomy & ECG
KAAP 310
The Electrocardiogram (ECG)
• As we discussed last week, the electrical activity of
the heart is determined by pacemakers (SA, AV
node)
• By placing sensitive electrodes on certain parts of
the body, we can recognize and record the
“echoes” of the heart depolarizing and
repolarizing
• Heart rate, Axis deviation (heart position), cardiac
arrthymias and mechanical activity of heart can all
be seen on a standard ECG.
A normal ECG reading
T Wave:
QRS Complex:
Repolarization
R & L ventriular
of right and
depolarization,
left ventriclesAtrial repolarization
P Wave: Depolarization of the right and left atria (atrial depolarization)
masked by QRS complex
Reading & Interpreting an ECG
Segments:
Isoelectric
Interval:
Period
Line:
Periods
of
Point
electrical
of no
of departure
recorded
activityofwithin
the depolarizing
and
activity
between
in the heartbeats
heart
and repolarizing actions
of the heart.
ECG Leads
• Particular arrangement of the electrodes with
respect to one another is called a lead.
• We will be using a 3-lead model
– A positive, negative and ground
electrode will be placed on the subject
• + on left ankle
• - on right wrist
• Ground on right ankle
ECG Notes
• QRS complex generally dominant in any ECG
recording
– Affected by many factors: Body mass, fat mass,
height, cardiovascular health (large LV mass will
change the look of the complex)
Large & Small Block Calculations
BioPac Lab
• Four conditions will be recorded: Supine,
Seated, Breathing deeply, and After exercise.
Minimize EMG artifact and baseline drift:
• Subject’s arms and legs must be relaxed.
• Subject must remain still and should not talk
during any recordings.
• Make sure electrodes do not peel up and that
the leads do not pull on the electrodes.
BioPac Lab
• First condition: Supine, eyes closed, relaxed
• Second condition: Stand up quickly, settle back
down into seated position
• Third condition: Five (5) deep inhales/exhales with
recorder counting
• Fourth condition: Exercise – 15 pushups or 15
jumping jacks. Mind the cables – may unclip if
necessary…don’t forget to re-attach!
• Optional active learning portion not required
• Call your TA when you have collected all data
Data Review
• After your data file has been transferred to
your laptop, open it with your BioPac analysis
software and begin analyzing your data
• Data & questions can be completed on your
computer and emailed to your TA (due next
week)
Heart Models
• While your group is waiting to work with the
BioPac software please use this time to begin
reviewing the heart models
• These same models will be used for your first
long quiz
• Feel free to use online resources and this
presentation
• Models will be available next week during our
dissection lab as well
Cardiac Anatomy
Interatrial Septum
Interventricular
Septum
Brachiocephalic trunk
Superior vena cava
Right
pulmonary
artery
Ascending aorta
Pulmonary trunk
Right
pulmonary
veins
Right
atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac
vein
Right
ventricle
Right marginal artery
Small cardiac vein
Inferior vena
cava
(b) Anterior
view
Left common carotid
artery
Left subclavian artery
Aortic
arch
Ligamentum arteriosum
Left pulmonary
artery
Left pulmonary veins
Auricle of
left
atrium
Circumflex artery
Left coronary artery
(in coronary
sulcus)
Left
ventricle
Great cardiac vein
Anterior
interventricular
artery (in anterior
interventricular
sulcus)
Apex
Figure 18.4b
Aorta
Left
pulmonary
artery
Left
pulmonary
veins
Auricle of left
atrium
Left
atrium
Great cardiac
vein
Posterior vein
of left
ventricle
Left
ventricle
Ape
x
Superior vena
cava
Right pulmonary
artery
Right pulmonary
veins
Right atrium
Inferior vena cava
Coronary
sinus
Right coronary
artery
(in
coronary sulcus)
Posterior
interventricular
artery (in posterior
interventricular sulcus)
Middle cardiac vein
Right
ventricle
(d) Posterior surface
view
Figure 18.4d
Superior
vena
cava
Anastomosis
(junction of
vessels)
Aorta
Pulmonar
y
trunkLeft atrium
Right
atriu
m
Right
coronar
y
artery Right
ventricle
Right
marginal Posterior
artery
interventricula
r
artery
(a) The major coronary
arteries
Left
coronar
y
artery
Circumfle
x
artery
Left
ventricle
Anterior
interventricula
r
artery
Figure 18.7a
Superior
vena
cava
Anterio
r
cardiac
veins
Great
cardia
c
vein
Coronary
sinus
Small cardiac vein
(b) The major cardiac
veins
Middle cardiac
vein
Figure 18.7b
Aorta
Superior vena
cava
Right
pulmonary
artery
Pulmonary
trunk
Right atrium
Right
pulmonary
veins
Fossa
ovalis
Pectinate muscles
Tricuspid valve
Right
ventricle
Chordae tendineae
Trabeculae
carneae
Inferior vena cava
Left
pulmonary
Left
artery
atrium
Left
pulmonary
veins
Mitral
(bicuspid)
valve
Aortic valve
Pulmonary
Left
valve
ventricle
Papillary muscle
Interventricular
septum
Epicardiu
Myocardiu
m
Endocardium
m
(e) Frontal
section
Figure 18.4e
Myocardium Pulmonary valve
Aortic
Tricuspid
Area
valveof
(right atrioventricular)
cutaway
Mitral
valve
valve
Tricuspid
Mitral
valve
(left
atrioventricular)
valve
Aortic
valve
Pulmonary
valve
Fibrous
skeleto
n
(a
)
Pulmonary valve
Aortic
Area
valveof
cutaway
Mitral valve
Tricuspid
valve
Anterio
r
(b
)
Myocardiu
m
Tricuspid
(right
atrioventricular)
valve
Mitral
(left
atrioventricular)
Aortic
valve
valve
Pulmonary
valve
Figure 18.8a