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Cardiovascular System Diseases and Disorders 147
■ Triglycerides (tri-GLISS-er-ides—stored energy
in the cells): should be under 200.
4. ECG to test the action of the heart.
Several other blood tests can be used to check
kidney dysfunction, which can also cause high blood
pressure.
■ Treatment. Treatment of hypertension depends on the
degree of hypertension and the number of risk factors
involved. If blood pressure is extremely high, antihyper
tensive medications might be prescribed immediately.
If hypertension is discovered in a milder form, lifestyle
changes or reduction of risk factors might be the initial
treatment. A low-salt, low-fat diet; stress-reducing exer
cise; and smoking cessation might solve the problem
(see Healthy Highlight feature “Prevention of Hyper
tension and Cardiovascular Disease”).
If this treatment is ineffective or inadequate, the
individual might be placed on diuretic medications.
Diuretics increase urine output, thus lowering blood
pressure. If further control is needed, other antihyper
tensive medications can be prescribed. Patient compli
ance with hypertension treatment is often a factor in
addressing this chronic disease. Lifestyle changes and
following the medication regimen for the rest of one’s
life are often difficult for the individual to manage.
■ Prevention. The CDC (2020) suggests that lifestyle
changes, such as those listed in the following Healthy
Highlight, can aid in preventing high blood pressure.
Healthy Highlight
Prevent High
Blood Pressure
T
o help reduce the risk of developing hypertension, CVD, and stroke, practice the
following lifestyle behaviors:
1. Eat a Healthy Diet
Choose healthy meal and snack options. Eat plenty of fresh fruits and vegetables.
2. Keep Yourself at a Healthy Weight
Being overweight or obese increases your risk for high blood pressure. To deter
mine if your weight is in a healthy range, you can calculate your body mass index
(BMI) at the CDC’s Assessing Your Weight website. In general, men are at risk
if their waist measurement is greater than 40 inches, and women are at risk if
their waist measurement is greater than 35 inches.
3. Be Physically Active
Physical activity can help keep you at a healthy weight and lower your blood
pressure. Adults should get at least 2 hours 30 minutes of moderate-intensity
exercise, such as brisk walking or bicycling, every week. That’s about 30 minutes
a day, five days a week. Children and adolescents should get 1 hour of physical
activity every day.
4. Do Not Smoke
■ Smoking raises your blood pressure and puts you at higher risk for heart attack
and stroke. If you do not smoke, do not start. If you do smoke, quitting will lower
your risk for heart disease.
5. Limit How Much Alcohol You Drink
Do not drink too much alcohol, which can raise your blood pressure. Men
should have no more than two alcoholic drinks per day and women should have
no more than one alcoholic drink per day.
6. Get Enough Sleep
Getting enough sleep is important to your overall health, and enough sleep is
part of keeping your heart and blood vessels healthy. Not getting enough sleep
on a regular basis is linked to an increased risk of heart disease, high blood
pressure, and stroke.
148 Chapter 8
Arteriosclerosis and Atherosclerosis
■ Description. Arteriosclerosis is a group of diseases
that are characterized by a loss of elasticity and a thick
ening of the artery wall. Atherosclerosis is the most
common form of arteriosclerosis. For this reason, these
terms are often used interchangeably; hardening of the
arteries is a lay term describing this condition. The com
mon result of arteriosclerosis is the gradual narrowing
of the vessel lumen (Figure 8-9). This narrowing leads
to a slowing or complete stoppage of blood flow to the
organs supplied by those vessels. Without proper blood
supply, these organs become ischemic and eventually
might die if blood supply is not restored.
An artery has a very smooth endothelium (inner lin
ing), like a nonstick finish. As with nonstick cookware,
food particles normally do not stick to the surface. If
the endothelium is damaged, however, blood material
begins sticking to the inner lining of the artery just as
food particles begin sticking to scratched cookware. The
artery wall surrounds this endothelium. Atherosclerosis
is a condition characterized by deposits of fatty or lipid
material in the wall of the artery (see Figure 8-9). These
fatty, cholesterol-containing deposits, called plaque,
damage the artery and interrupt blood flow by
■ pushing into the endothelium, thus damaging the
inner lining. Damage to this lining allows blood
material to stick to the inner lining and occlude the
lumen.
■ causing the artery wall to harden or lose elasticity.
This loss of elasticity increases blood pressure and
Cross-sections through a coronary artery
undergoing progressive atherosclerosis
and arteriosclerosis
Normal artery with open
lumen
Small
Elevated cholesterol
and blood fats
Enlarging atheroma
(plaque deposit)
Moderate atherosclerotic
narrowing of lumen
Moderate
myocardial ischemia
Complete/almost complete
occlusion, with hardening
due to calcium deposition
Angina pectoris
Occlusion of
left coronary
artery
A myocardial infarction
(“heart attack”) on left
side of the heart
Severe acute
myocardial ischemia
and infarction
Figure 8-9 Atherosclerosis: narrowing of arterial lumen.
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Cardiovascular System Diseases and Disorders 149
increases the heart’s workload. A hardened vessel is
not able to expand and accommodate the surge of
blood caused by the beat of the heart.
■ thickening of the artery wall to the point that the
lumen is partially or completely occluded.
■ leading to the formation of plaque that often ulcer
ates or breaks loose, forming an embolus (EM-boh-
lus; material floating in the blood) that can stick in a
vessel and occlude or stop blood flow, leading to isch
emia or death of the organs supplied by that vessel.
Narrowing of the lumen of the artery in all the afore
mentioned ways increases blood pressure, increases the
workload of the heart, and decreases blood supply to
the organs. Increased blood pressure stretches the hard
ened arteries, causing further artery damage and further
increasing workload on the heart.
Atherosclerosis can affect all arteries in the body,
but four major areas are often affected by atheroscle
rosis, many times leading to disability or mortality
(Figure 8-10).
These major areas affected are the following:
1. Coronary arteries These arteries feed the muscle
tissue of the heart. Atherosclerosis of these arter
ies leads to coronary artery disease, also called
coronary heart disease. Consequences of coro
nary artery disease can include MI (heart attack).
Affected site
Carotid arteries
Aorta
Coronary arteries
Renal arteries
Iliac arteries
Femoral arteries
Tibial arteries
Cerebral arteries
Potential complication
Atherosclerotic
carotid artery
Stroke
Aneurysm
Angina, myocardial
infarction
Hypertension
Peripheral vascular disease
Peripheral vascular disease
Peripheral vascular disease
Figure 8-10 Atherosclerosis: major areas affected.
150 Chapter 8
2. Cerebral arteries These arteries feed brain tis
sue. Atherosclerosis of these arteries can lead
to a cerebrovascular accident (CVA), commonly
called a stroke.
3. Aorta This artery is the largest artery in the
body and is responsible for carrying blood to
the general circulatory system. Atherosclerosis
of this artery in any area can lead to aneurysms.
4. Peripheral arteries Peripheral arteries primar
ily feed the extremities (arms and legs). Athero
sclerosis of these arteries can lead to peripheral
vascular disease.
■ Etiology. The cause of atherosclerosis is unknown,
but it is thought to be the result of a combination of
factors, some of which are not controllable, but many
are and can be altered by a change in lifestyle. Important
risk factors include the following.
Non-controllable Factors
■ Heredity Atherosclerosis appears to run in families.
This might be related to common diet or, in some
instances, a clear genetic tendency to develop hyper
cholesterolemia (hyper = increased, cholesterol,
emia = blood).
■ Age Atherosclerosis is considered a degenerative dis
ease because all adults over the age of 30 have some
degree of plaque formation. In general, the older the
person, the more atherosclerosis is present.
■ Sex Men have more atherosclerosis present than
women until after female menopause, at which time,
the incidence becomes more equal.
■ Diabetes Individuals with diabetes have more exist
ing atherosclerosis than those who do not have dia
betes. However, if their diabetes is type 2 and related
to obesity, it is considered a controllable factor.
Controllable Factors
■ Diet Obese individuals have more atherosclerosis
present than individuals in the normal weight range.
The higher the diet in carbohydrates and fats, the
higher is the incidence of atherosclerosis.
■ Sedentary lifestyle A lack of exercise increases the
risk of developing atherosclerosis.
■ Cigarette smoking This is one of the most important
risk factors. Stopping smoking is 10 times more effec
tive in reducing risk than a combination of exercise
and diet control.
■ Stress Stress increases blood pressure, but research
does not support the idea that stress increases
atherosclerosis.
■ Hypertension The higher the blood pressure, the
greater is the risk of developing atherosclerosis. It is
difficult to determine which of these diseases occurs
first. Atherosclerosis causes an increase in blood
pressure, and hypertension leads to an increase in
atherosclerosis. Often, hypertension and atheroscle
rosis occur simultaneously, each complicating the
treatment of the other.
■ Symptoms. Symptoms of atherosclerosis appear late
in the disease process and vary, depending on the area
affected.
■ Diagnosis. Diagnosis of atherosclerosis is by blood
pressure measurement, arteriograms, and X-ray. Dop
pler studies to determine blood flow also can be used.
■ Treatment. Treatment is aimed at reducing symptoms
as they arise. Surgery to open the artery and remove
plaque may be used. This surgical treatment is called
endarterectomy (END-ar-ter-ECK-toh-me; endo =
inside, arter = artery, ectomy = excision). If the artery
is damaged, it might be surgically treated with the place
ment of stents or bypassed with a graft.
■ Prevention. Prevention of atherosclerosis includes
exercise, estrogen medication after menopause, and
changing lifestyle to reduce risk factors. Detailed
methods are discussed in the Healthy Highlight fea
ture “Prevention of Hypertension and Cardiovascular
Disease.”
Peripheral Vascular Disease
■ Description. Peripheral vascular disease (PVD) refers
to any disease of arteries or veins peripheral or outside
the heart and head. By far, the most common PVD is
PAD, not PVD. Both PVD and PAD are commonly
caused when vessels are partially or completely occluded
or stopped up by arteriosclerotic plaque. This common
connection between PVD and PAD often leads to an
interchangeable use of these two terms.
PAD affects millions of Americans. PAD becomes
more common with age, but the main risk factor is
smoking (National Institute of Health, 2020). While
PAD may affect the arteries of the arms, kidneys, and
stomach, it more commonly affects the legs.
■ Etiology. PVD and PAD are caused by atherosclerotic
plaque, primarily in the arteries supplying blood to the
legs. This occlusion by plaque can be chronic or acute.
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Cardiovascular System Diseases and Disorders 151
Chronic occlusion is generally related to a progressive
narrowing of the femoral and popliteal arteries. As these
arteries become occluded, the blood supply to the leg
muscles is decreased. Having PAD usually indicates
the potential for arterial disease involving the coronary
arteries within the brain.
■ Symptoms. Individuals with PVD have adequate
blood supply to leg muscles during minimal activity
such as sitting or slow walking. If activity is increased
to brisk walking or running, blood supply becomes
inadequate, causing leg muscle cramps. Resting the
legs will relieve the muscle cramps and allow the mus
cles once again to receive the needed amount of blood
flow. This condition of developing muscle cramps that
are relieved with rest and increase with activity is called
intermittent claudication (KLAW-dih-KAY-shun).
■ Diagnosis. Diagnosis is critical because people with
PVD are at high risk for heart attack and stroke. The
classic symptom of PAD is intermittent claudication.
Other tests include
■ Feeling for a pulse in the foot. A Doppler flow probe
can quickly pick up a pulse if one is present.
■ ABI (the measurement of the blood pressure in the
arm compared to the blood pressure in the leg).
■ A treadmill test to attempt to induce intermittent
claudication.
■ Angiography and magnetic resonance imaging
(MRI) to determine the location and thickness of the
atherosclerosis (plaque).
■ Treatment. Treatment for PAD includes management
of leg pain and stopping the progression of the athero
sclerosis. These goals may be accomplished with life
style changes. A physician-prescribed walking program
may not only increase the distance walked, but also
improve the body’s use of oxygen. These improvements
in general physical condition may decrease or eliminate
the associated leg pain. People who smoke may be able
to accomplish these goals by not smoking because this
is the single most important lifestyle change.
If further treatment is needed, it may include medi
cation to prevent blood clots, lower blood pressure and
cholesterol, and control pain. If these treatments are
ineffective, angioplasty or bypass surgery may be nec
essary. Chronic occlusion of the artery may be treated
with a femoral popliteal bypass graft.
■ Prevention. Risk can be reduced by following the
guidelines in the Healthy Highlight feature “Prevention
of Hypertension and Cardiovascular Disease.”
Acute occlusion of the peripheral arteries often
involves smaller arteries supplying blood to the feet and
toes. This decrease in blood supply may cause ulcers on
the feet and toes, sores that do not heal, gangrene, or
infections in the extremities. In some cases, amputation
may be necessary.
Aneurysm
■ Description. Aneurysm (AN-you-rizm) is a weaken
ing in the wall of an artery that allows the vessel to bulge
or rupture (Figure 8-11).
■ Etiology. This weakening is often due to atheroscle
rosis but also might be due to a congenital defect or
injury.
■ Symptoms. Aneurysms are usually asymptomatic
and are often discovered accidentally during phys
ical examinations or X-rays. The most common area
affected is the abdominal aorta. Rupture of an aneurysm
is a medical emergency, often causing death due to mas
sive hemorrhage and shock.
Dissecting
Figure 8-11 Three types of aneurysm.
152 Chapter 8
■ Diagnosis. A thorough physical examination can lead
to the discovery of an aortic aneurysm. Placing a stetho
scope on the abdomen allows a physician to hear the
abnormal blood flow through the artery. Smaller aneu
rysms and those located in other areas are more difficult
to hear and might be discovered by angiogram. Other
diagnostic tests include computerized tomography (CT)
and MRI scans.
■ Treatment. Treatment is aimed at repairing the aneu
rysm before rupture. Surgical resection and grafting are
commonly performed (Figure 8-12).
■ Prevention. Preventing atherosclerosis and hyperten
sion aids in preventing an aneurysm. Congenital aneu
rysms cannot be prevented.
Coronary Artery Disease
■ Description. Coronary artery disease (CAD), often
called coronary heart disease (CHD), is the narrow
ing of arteries that supply blood to the myocardium,
the heart muscle. It is the leading cause of death in the
United States today.
(A)
(C)
Figure 8-12 Abdominal aneurysm surgical resection (A) Abdominal aneurysm surgical resection. (B) Model of Stent graft
material and placement. (C) Synthetic graft in place.
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Cardiovascular System Diseases and Disorders 153
■ Etiology. This disease is commonly due to
atherosclerosis.
■ Symptoms. Progressive or slow narrowing of the
arteries leads to ischemia of the heart muscle and symp
toms of angina. Some muscle cells can actually die and
be replaced with scar tissue. This scar tissue cannot
function like muscle tissue, causing an increase in the
workload of the remaining heart muscle. Congestive
heart failure often results.
If a coronary artery becomes blocked to the point
that heart muscle oxygen demands cannot be met,
the heart muscle dies. Occlusion can progress slowly
as plaque builds up in the vessel, or it can develop
suddenly as the result of a thrombus (THROM-bus;
a blood clot attached to a vein or artery) or embolus
(traveling blood clot, free in the circulatory system,
more dangerous than a thrombus). This dead muscle is
called an infarct or myocardial infarct. The process of
the myocardium dying is called MI.
Slow, progressive occlusion of the arteries often
leads to the development of collateral arteries that
extend into ischemic tissue. Collateral circulation pro
vides some protection against ischemia and infarction.
For this reason, infarction caused by slow occlusion
often has a better outcome than infarction caused by
sudden occlusion of a vessel.
■ Diagnosis. Diagnosis of CAD is made from a history
of symptoms, ECG, and angiograms. Symptoms usually
do not develop until the vessels are severely occluded.
■ Treatment. The treatment of CAD is aimed at increas
ing blood flow or decreasing oxygen needs. Angina is
often treated with rest and vasodilators. A coronary
artery angioplasty (AN-jee-oh-PLAS-tee; angio =
vessel, plasty = surgical repair) might be attempted to
open the vessel by passing a catheter into the artery and
inflating a balloon on the catheter to push the plaque
against the vessel wall, thus widening the lumen of the
vessel (Figure 8-13). If a wire mesh is left in place to
hold the artery open, this is called a stent placement.
Another common surgical treatment for CAD is a
coronary artery bypass graft, commonly called a CABG
(pronounced cabbage). This procedure bypasses the
occlusion (Figure 8-14). Mammary vessels from the
breast area and saphenous vessels from the legs are
often used for the bypass.
■ Prevention. It is very important for individuals with
CAD to reduce atherosclerotic risk factors. Diet, exer
cise, and a no-smoking regimen are prescribed to slow
the progression of the disease.
Figure 8-13 Coronary artery angioplasty.
Diseases of the Heart
Diseases of the heart are frequently due to the atheroscle
rotic narrowing of the coronary arteries. The result of this
is usually angina, a heart attack (MI), or both. Decreasing
lifestyle behaviors that contribute to the development of
atherosclerosis decreases one’s risk for heart disease.
Consider This...
It is possible to die from a “broken heart”; it
is called stress cardiomyopathy.
154 Chapter 8
Aorta
Saphenous
vein grafts
Figure 8-14 Coronary artery bypass graft (CABG
).
Coronary Heart Disease
CHD, CAD, and arteriosclerotic heart disease are all
one and the same. This disease was previously discussed
as CAD. CHD is the most common type of heart disease
in the United States. The risk of this disease rises rapidly
with increased age.
Angina Pectoris
■ Description. Angina pectoris (an-JIGH-nah PECK-
toh-riss) is often abbreviated to angina. Angina is com
monly called chest pain.
■ Etiology. Angina pectoris is caused by lack of oxy
gen to the myocardium (heart muscle). Atherosclerosis
is the leading cause of angina, although in some cases,
it can be brought on by a spasm of the muscles in the
arteries that restricts blood flow to the heart. Angina is
commonly a symptom of impending MI.
■ Symptoms. During an attack, the individual might
complain of a suffocating tightness in the chest that radi
ates to the left arm, neck, and jaw (Figure 8-15). Angina
usually occurs during periods of increased workload on
the heart such as those experienced with physical exer
cise, emotional stress, or digestion of a large meal.
■ Diagnosis. A thorough physical exam, along with
blood test, electrocardiogram, and cardiac catheteriza
tion, assists in diagnosis. Blood tests include cholesterol
and triglyceride blood levels. An electrocardiogram can
assist in recognizing abnormal heart function. A cardiac
catheterization is the most definitive procedure to dis
cover the cause of angina.
■ Treatment. Treatment of angina is to decrease the
workload on the heart by stopping the aggravating
activity and increasing blood flow to the heart mus
cle. Vasodilatation of the coronary arteries or those
that supply the heart muscle will improve blood flow
and help relieve the oxygen deficit. Nitroglycerin is a
vasodilator that is commonly used. It is administered
sublingually (under the tongue) and usually provides
immediate relief. Individuals suffering with angina need
medical attention.
■ Prevention. Angina can be prevented or controlled
by making healthy lifestyle choices as previously listed.
Myocardial Infarction
■ Description. The term myocardial infarction
(MY-oh-KAR-dee-al in-FARK-shun) comes from the
meanings of the words myocardium (heart muscle)
and infarction (tissue death from lack of oxygen). It is
Low-Fat Diets: Are
They Necessary?
Complementary and Alternative Therapy
I
n the past, most major health organizations recommended low-fat diets to maintain
a healthy heart but that has changed in recent years. Most nutrition experts have
switched from telling consumers to limit the fats in their diet to focus on overall healthy
eating. This includes eating moderate portions, adding more vegetables and fruits to the
daily intake, selecting whole grains, eating more nuts, seeds, olives, avocados, and fish,
and choosing low-fat protein sources.
Source: Harvard Heart Letter (2020)
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Cardiovascular System Diseases and Disorders 155
Figure 8-15 Patterns of angina.
commonly called a heart attack and often leads to car
diac arrest—stopping of the heartbeat.
■ Etiology. MI occurs when the heart muscle does not
get adequate oxygen due to a decrease in blood supply,
an increase in oxygen need, or a combination of both.
The decrease in blood supply is most commonly caused
by the atherosclerotic plaque of CAD. Any activity that
increases the oxygen need of the heart beyond the sup
ply level can lead to a myocardial infarct. Such activi
ties can include shock, hemorrhage, stress, or excessive
physical exertion.
■ Symptoms. Classic symptoms of an MI include severe
chest pain with diaphoresis (sweating) and nausea.
Often, the symptoms are not as obvious and can include
referred pain in the left arm, neck, and jaw, along with
a discomfort similar to bad or unrelieved indigestion.
According to the American Heart Association
(AHA, 2021), women often experience different symp
toms than men. Women’s most common heart attack
symptom is also chest pain or discomfort. Often, how
ever, symptoms in women may be less severe and more
“flu-like” yet just as dangerous as the classic signs and
may include
■ pain or discomfort in one or both arms, the back,
or stomach.
■ shortness of breath with or without chest pain.
■ breaking out in a cold sweat, nausea, or
lightheadedness.
The severity of symptoms can depend on the size
of the infarction. If the area is small, symptoms might
be mild, and the infarction can be labeled a silent MI. If
the infarcted area is large, symptoms can include car
diogenic shock and death. Myocardial infarction is the
number one killer of women.
■ Diagnosis. The diagnosis of MI is made by history
and physical examination along with an electrocardio
gram and blood testing. Two specific cardiac blood tests
indicative of MI are creatine phosphokinase (CPK) and
troponin.
■ Treatment. Treatment of an MI involves immediate
attention to prevent shock, relieve respiratory distress,
and decrease the workload on the heart. The individ
ual should be assisted into a lying position. Tight or
restrictive clothing should be loosened to improve
respiratory function. If cardiac arrest has occurred,
appropriate cardiopulmonary resuscitation (CPR)
should be administered immediately, and the individ
ual should be transported immediately to a medical
facility.
Medical treatment involves the administration of
oxygen and pain medication, and medication to treat
arrhythmias is often needed. Intravenous thrombo
lytic, or clot busting, therapy using a tissue plasmino
gen activator (TPA) or streptokinase might be used to
open the occlusion and restore blood flow. Education
following an MI is aimed at prevention by possible
changes in lifestyle to reduce risk factors. Smoking
cessation, dietary changes, and exercise are usually
recommended.
The main site involved in an MI is the left ven
tricle. This is the hardest working area of the heart
156 Chapter 8
and has the greatest need for oxygen. Tissue changes
that appear with an infarction depend on the degree
or extent of oxygen deprivation suffered by the cells.
Under microscopic examination, the infarcted area
might take on a bull’s-eye appearance (Figure 8-16).
The central core is made up of cells that are dead or
necrotic with severely damaged cells surrounding this
core. These cells might regain function within a few
weeks, or they might die, thus extending the infarcted
area. On the outer border of the bull’s-eye pattern are
cells that suffered from ischemia. These cells usually
live and can regain function.
Death of myocardial cells brings about a release of
certain enzymes and proteins (CPK and troponin) into
the general circulation. Blood tests to measure these lev
els assist in determining the amount of dead or necrotic
tissue and the severity and time of the attack. Blood lev
els, along with an ECG, history, and physical examina
tion, often confirm the diagnosis of MI.
Tissue infarction and injury naturally cause the
inflammatory response. With this response comes an
outpouring of polymorphonuclear cells (PMNs) and
macrophages. Within the first 5 to 7 days, macrophages
phagocytize the dead tissue, often leaving a thin, weak
myocardial layer. The possibility of rupture and sudden
death is greatest at this time. Any activity that increases
the workload of the heart or increases blood pressure
should be avoided. Rest is essential during this time.
Within 2 weeks, the infarcted area is healing with
granulation tissue. This tissue is not made of muscle tis
sue; it is scar tissue. This scar will not stretch or contract
like normal muscle and it will never function as normal
heart tissue. The inability of this scarred area to func
tion increases workload on the remaining heart muscle
cells for the rest of the individual’s life.
■ Prevention. Risk factors for MI are the same as for
CAD and primarily include hypertension, cigarette
smoking, a sedentary lifestyle, obesity, and a high-
cholesterol diet. Controlling risk factors is the primary
way to prevent MI.
Hypertensive Heart Disease
■ Description. Hypertensive heart disease is a group of
disorders caused by hypertension. It is the number one
cause of death associated with hypertension and is the
result of long-term hypertension.
■ Etiology. Any disease or disorder that causes a
chronic elevation in blood pressure can lead to hyper
tensive heart disease. Essential hypertension, arte
riosclerosis, atherosclerosis, and kidney diseases are
common causes.
■ Symptoms. As previously discussed, chronic hyper
tension leads to increased workload on the heart, caus
ing cardiac hypertrophy and, eventually, heart failure.
■ Diagnosis. Diagnosis is made by a thorough history
and physical examination. X-rays revealing enlarge
ment of the heart, along with abnormal heart function
as determined by an echocardiogram, are indicative
of this disease. Late in the course of the disease, there
Right pulmonary
veins
Left pulmonary veins
Occlusion
Necrosis (infarction)
Injury
Ischemia
Left ventricle
Vena cava
Auricle of
right atrium
Right coronary
artery
Pericardium
Right ventricle
Figure 8-16 Myocardial infarction: areas of ischemia.
Aorta
Pulmonary artery
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