Download Angina - Philadelphia College of Osteopathic Medicine

CASE 1
Group C
A 50-year-old football coach visited the doctor complaining
of chest pain. The patient said he has been experiencing chest pain
for the past three months with the intensity of pain increasing over
the past two weeks. The pain is located in his left shoulder,
radiating from there to the sternum and to the pit of the stomach.
The patient tells the doctor that the pain usually comes while he is
coaching football practice, or other similar physical activity. He
finds that if he takes a 5 to 10 minute break the chest pains go
away. Upon physical examination, the doctor finds no abnormality
in movement of the shoulder joint. There is an absence of pain
while abducting and laterally rotating the arm, thus ruling out the
possibility of inflammation of the pectoralis major muscle.
An echocardiogram (EKG), which examines the size and
functioning of the heart, reveals that the patient’s heart is slightly
enlarged. When the doctor palpates two arteries that run
superficially in the arm, the radial and brachial arteries, he notes
that they are thickened. The physician presupposes that this is due
to the buildup of plaque within the arteries.
What is the Function of the Heart?
• Pumps blood throughout the
entire body
• Beats approximately 72 beats
per minute supplying cells of
the body with nutrients they
need to survive
• When looking at an
image, the right and left
are defined as the right
and left of the patient.
• This means right and left
are reversed when
looking at an image.
• In this image of the
heart, “right” is to the
left of the image and
“left” is to the right of
the image.
RIGHT
LEFT
The Heart Contains
Four Compartments:
2 Atrial
and
2 Ventricular
Compartments
See video of the heart and lungs in the thoracic cavity
Atrial Compartments of the Heart
The atria of the heart are
receiving chambers. The right
atrium receives blood from
the body via the superior and
inferior vena cava and the left
atrium receives blood from
the lungs via the pulmonary
veins. The SA node is also
contained within the right
atrium and is the site at which
electrical impulse to the heart
originates.
Pectinate
Muscle
Right
Atrium
Fossa Ovalis
The atrial chambers contain pectinate
muscles within the walls of the chamber.
Blood passes from the atria to the
ventricles through a one-way opening
called the atrioventricular valve.
Atrial
Compartments
Ventricular Compartments of the Heart
The ventricles are the discharging
chambers. The right ventricle pumps
blood away from the heart to the
lungs via the pulmonary arteries and
the left ventricle pumps blood away
from the heart to the body through
the aorta.
The ventricular chambers contain
trabeculae carneae muscle.
Ventricular chambers are more
muscular and larger in size because
they must pump blood away from the
heart into a system under higher
pressure, the pulmonary arteries or
Trabeculae
aorta. The left ventricle is the most
muscular since it functions to pump
Carneae
blood to the entire body via the aorta. Muscle
See video of the heart chambers
Ventricular
Compartments
Right
Ventricle
Papillary
Muscle
As blood fills the atria, the
pressure rises and forces the blood
into the ventricle through the oneway atrioventricular valve. The
period of ventricular filling is
called diastole in the cardiac
cycle. When a physician listens
with a stethoscope, the ventricle
filling with blood sounds like a
“lub”.
When the ventricles fill, an
electrical impulse signals them to
contract to push the blood into the
pulmonary artery (right ventricle)
or into the aorta (left ventricle).
This period of ventricular
contraction is called systole in the
cardiac cycle. When a physician
listens with a stethoscope, the
ventricle squeezing blood out of
the heard sounds like a “dub”.
What is the direction of blood
flow in the heart?
How Does Blood
Flow in the
Heart?
1
The right atrium receives
deoxygenated blood from the
body
1
2
Blood then flows to the
right ventricle and is
pumped to the lungs to
become oxygenated
2
How Does Blood
Flow in the
Heart?
3
Oxygenated blood from the
lungs is brought back into the
heart and deposited into the
left atrium
4
Blood then flows into the left
ventricle
5
Oxygenated blood is then
distributed to the body via
the aorta
To The Body
5
3
4
See video of the heart and its great vessels
Interatrial Septum
Interventricular Septum
What would happen if either the
tricuspid or mitral valves were
damaged ?
The septa of the heart divide
the left and right sides of the
heart. There are two types of
septa in the heart: the thin,
membranous septum
between the right and left
atria and the thick, muscular
septum between the right
and left ventricles. Both
septa help to maintain
deoxygenated blood on the
right side and oxygenated
blood on the left side of the
heart.
The atrial and ventricular
compartments remain
divided by valves known as
the tricuspid and mitral
valves.
Tricuspid Valve
Mitral Valve
The tricuspid valve is found in between the right
atrium and the right ventricle. It is called tricuspid
because it has three cusps. The mitral valve is found in
between the left atrium and the left ventricle and has
two cusps. Both valves prevent backflow of blood into
the preceding atrium. The papillary muscle within the
walls of the ventricles attach to either the tricuspid or
mitral valve and help to regulate the opening and
closing of the valves.
Pulmonary Valve
Pulmonary
• The pulmonary valve is
Valve
found in between the
right ventricle and the
pulmonary artery
leading to the lungs.
• The pulmonary valve
contains three cusps.
• The pulmonary valve
helps to regulate blood
flow into the lungs.
Aortic Valve
 The aorta is the largest
blood vessel in the body.
 Blood passing from the left
ventricle to the aorta must
pass through the aortic
valve.
 The aortic valve contains
three cusps including the
right, posterior and left
cusps
How does blood enter the
coronary arteries?
Aortic Valve
Opening to
Right
Coronary
Artery
Opening to
Left
Coronary
Artery
Aortic Cusp
 The right and left cusps of the
aortic valve contain sinuses
leading to the right and left
coronary arteries. The right
and left coronary arteries
provide oxygenated blood
supply to the muscle tissue of
the heart.
Right Coronary Artery
The coronary arteries provide blood supply to the heart. In particular,
the right coronary artery provides blood supply to the right side of the
heart which includes the right atrium and the right ventricle.
The right coronary artery branches into three main branches:
Sinoatrial(SA) nodal branch, the Right Marginal Branch, and the
Posterior Interventricular Branch.
Right
Marginal
Branch
Right
Coronary
Artery
Anterior View
Posterior View
Posterior
Interventricular
Branch
Left Coronary Artery
The left coronary artery
Left Coronary
Artery
provides blood supply to the
left side of the heart, which
includes the left atrium, the
left ventricle and the
muscular septum between
the ventricles. The left
coronary artery branches
into two main branches: the
Anterior Interventricular
Branch and the
Circumflex branch.
Circumflex Branch
Anterior Interventricular
Branch
See video of the blood vessels that supply the heart muscle
Blockage of Coronary Arteries
Plaque in
Coronary
Artery
The coronary arteries
may gradually become
occluded due to the build
up of plaque over a
period of time. Plaque is
composed of deposits of
fats, cholesterol, and
calcium within the
artery’s walls.
Atherosclerosis, the
build up of plague over a
long period of time, often
results in coronary
artery disease.
How would blockage of the coronary arteries cause a
problem during physical activity?
If the right coronary artery is blocked by a build-up of
plaque, the heart is unable to receive an adequate amount of
oxygen due to a shortage in the blood supply. During physical
activity, such as coaching football practice, the patient’s heart has
to contract more rapidly to supply blood to the body. This,
ultimately causes the patient to experience a sensation of pain
within the chest region.
An angiography, which tests for blockage of the coronary
arteries, confirms that the patient has coronary artery disease
causing approximately 85% of the right coronary artery to be
blocked and 70% of the anterior interventricular artery to be
blocked. Based on the clinical observations and tests, the
physician diagnoses the patient with angina, a pain originating
from the heart that is a result of low blood oxygen reaching the
heart muscle.
The doctor prescribes medication to dilate the coronary
arteries, thus allowing more blood oxygen to reach tissues of the
heart. The patient is also put on a low fat diet and regular
exercise program to promote cardiovascular wellness.