Peripheral
Vascular Disease (PVD) / Peripheral Arterial Disease
(PAD)
Peripheral
vascular disease (PVD) is a slow and progressive
circulation disorder. It may involve disease in
any of the blood vessels outside of the heart
and diseases of the lymph vessels - the arteries,
veins, or lymphatic vessels. Organs supplied by
these vessels such as the brain, heart, and legs,
may not receive adequate blood flow for ordinary
function. However, the legs and feet are most
commonly affected, thus the name peripheral vascular
disease.
Conditions
associated with PVD that affect the veins include
deep vein thrombosis (DVT), varicose veins, and
chronic venous insufficiency. Lymphedema is an
example of PVD that affects the lymphatic vessels.
When
PVD occurs in the arteries outside the heart,
it may be referred to as peripheral arterial disease
(PAD). However, the terms "peripheral vascular
disease" and "peripheral arterial disease"
are often used interchangeably. In the US, 10
million people have peripheral artery disease.
PAD occurs in 5 percent of adults older than 50
and in 20 percent of adults older than 70. It
is frequently found in people with coronary artery
disease, because atherosclerosis, which causes
coronary artery disease, is a widespread disease
of the arteries.
Conditions
associated with PAD may be occlusive (occurs because
the artery becomes blocked in some manner) or
functional (the artery either constricts due to
a spasm or expands). Examples of occlusive PAD
include peripheral arterial occlusion and Buerger's
disease (thromboangiitis obliterans). Examples
of functional PAD include Raynaud's disease
and phenomenon and acrocyanosis.
PVD
is often characterized by a narrowing of the vessels
that carry blood to the leg and arm muscles. The
most common cause is atherosclerosis (the buildup
of plaque inside the artery wall). Plaque reduces
the amount of blood flow to the limbs and decreases
the oxygen and nutrients available to the tissue.
Clots may form on the artery walls, further decreasing
the inner size of the vessel and potentially blocking
off major arteries.
Other
causes of peripheral vascular disease may include
trauma to the arms or legs, irregular anatomy
of muscles or ligaments, or infection. Persons
with coronary artery (arteries that supply blood
to the heart muscle) disease are frequently found
to also have peripheral vascular disease.
The
term "peripheral vascular disease" encompasses
several different conditions. Some of these conditions
include, but are not limited to, the following:
- atherosclerosis -
the build-up of plaque inside the artery wall.
Plaque is made up of deposits of fatty substances,
cholesterol, cellular waste products, calcium,
and fibrin. The artery wall then becomes thickened
and loses its elasticity. Symptoms may develop
gradually, and may be few, as the plaque builds
up in the artery. However, when a major artery
is blocked, a heart attack, stroke, aneurysm,
or blood clot may occur, depending on where
the blockage occurs.
- Buerger's disease
(thromboangiitis obliterans) - a
chronic inflammatory disease in the peripheral
arteries of the extremities leading to the development
of clots in the small- and medium-sized arteries
of the arms or legs and eventual blockage of
the arteries. Buerger's disease most commonly
occurs in men between the ages of 20 and 40
who smoke cigarettes. Symptoms include pain
in the legs or feet, clammy cool skin, and a
diminished sense of heat and cold.
- chronic venous insufficiency
- a prolonged condition in which one or
more veins do not adequately return blood from
the lower extremities back to the heart due
to damaged venous valves. Symptoms include discoloration
of the skin and ankles, swelling of the legs,
and feelings of dull aching pain, heaviness,
or cramping in the extremities.
- deep vein thrombosis
(DVT) - a clot that occurs in a
deep vein, and has the potential to dislodge,
travel to the lungs, occlude a lung artery (pulmonary
embolism), and cause a potentially life-threatening
event. It is found most commonly in those who
have undergone extended periods of inactivity,
such as from sitting while traveling or prolonged
bed rest after surgery. Symptoms may be absent
or subtle, but include swelling and tenderness
in the affected extremity, pain at rest and
with compression, and raised vein pattern.
- Raynaud's phenomenon
- a condition in which the smallest
arteries that bring blood to the fingers or
toes constrict (go into spasm) when exposed
to cold or as the result of emotional upset.
Raynaud's most commonly occurs in women
between the ages of 18 and 30. Symptoms include
coldness, pain, and pallor (paleness) of the
fingertips or toes.
- thrombophlebitis -
a blood clot in an inflamed vein, most commonly
in the legs, but it can also occur in the arms.
The clot can either be close to the skin (superficial
thrombophlebitis) or deep within a muscle (deep
vein thrombosis). It may result from pooling
of blood, venous wall injury, and altered blood
coagulation. Symptoms in the affected extremity
include swelling, pain, tenderness, redness,
and warmth.
- varicose veins -
dilated, twisted veins caused by incompetent
valves (valves that allow backward flow of blood)
allowing blood to pool. It is most commonly
found in the legs or lower trunk. Symptoms include
bruising and sensations of burning or aching.
Pregnancy, obesity, and extended periods of standing
intensify the symptoms.
A risk
factor is anything that may increase a person's
chance of developing a disease. It may be an activity,
diet, family history, or many other things. Risk
factors for peripheral vascular disease include
factors which can be changed or treated and factors
that cannot be changed.
Risk
factors that cannot be changed include the following:
- age (especially older
than 50)
- history of heart disease
- male gender
- diabetes mellitus (type
1 diabetes)
- postmenopausal women
- family history of dyslipidemia
(elevated lipids in the blood, such as cholesterol),
hypertension, or peripheral vascular disease
Risk
factors that may be changed or treated include:
- coronary artery disease
- impaired glucose tolerance
- dyslipidemia
- hypertension (high
blood pressure)
- obesity
- physical inactivity
- smoking or use of tobacco
products
Those
who smoke or have diabetes mellitus have the highest
risk of complications from peripheral vascular
disease because these risk factors also cause
impaired blood flow.
Approximately
half the people diagnosed with peripheral vascular
disease are symptom free. For those experiencing
symptoms, the most common first symptom is intermittent
claudication in the calf (leg discomfort described
as painful cramping that occurs with exercise
and is relieved by rest). During rest, the muscles
need less blood flow, so the pain disappears.
It may occur in one or both legs depending on
the location of the clogged or narrowed artery.
Other
symptoms of peripheral vascular disease may include:
- changes in the skin,
including decreased skin temperature, or thin,
brittle shiny skin on the legs and feet
- diminished pulses in
the legs and the feet
- gangrene (dead tissue
due to lack of blood flow)
- hair loss on the legs
- impotence
- non-healing wounds
over pressure points, such as heels or ankles
- numbness, weakness,
or heaviness in muscles
- pain (described as
burning or aching) at rest, commonly in the
toes and at night while lying flat
- pallor (paleness) when
the legs are elevated
- reddish-blue discoloration
of the extremities
- restricted mobility
- severe pain
- thickened, opaque toenails
The
symptoms of peripheral vascular disease may resemble
other conditions. Consult your physician for a
diagnosis.
In addition
to a complete medical history and physical examination,
diagnostic procedures for peripheral vascular
disease may include any, or a combination, of
the following:
- angiogram -
an x-ray of the arteries and veins to detect
blockage or narrowing of the vessels. This procedure
involves inserting a thin, flexible tube into
an artery in the leg and injecting a contrast
dye. The contrast dye makes the arteries and
veins visible on the x-ray.
- ankle-brachial index
(ABI) - a comparison of the blood
pressure in the ankle with the blood pressure
in the arm using a regular blood pressure cuff
and a Doppler ultrasound device. To determine
the ABI, the systolic blood pressure (the top
number of the blood pressure measurement) of
the ankle is divided by the systolic blood pressure
of the arm.
- blood lipid profile
- a blood test to measure the levels
of each type of fat in your blood: total cholesterol,
LDL cholesterol, HDL cholesterol, triglycerides,
and others.
- Doppler ultrasound
flow studies - uses high-frequency
sound waves and a computer to create images
of blood vessels, tissues, and organs. Doppler
technique is used to measure and assess the
flow of blood. Faintness or absence of sound
may indicate an obstruction in the blood flow.
- magnetic resonance
angiography (MRA) - a noninvasive
diagnostic procedure that uses a combination
of a large magnet, radiofrequencies, and a computer
to produce detailed images of organs and structures
within the body. An MRA is often used to examine
the heart and other soft tissues and to assess
blood flow.
- treadmill exercise
test - a test that is given while
a patient walks on a treadmill to monitor the
heart during exercise.
- photoplethysmography
(PPG) - an examination comparable
to the ankle brachial index except that it uses
a very tiny blood pressure cuff around the toe
and a PPG sensor (infrared light to evaluate
blood flow near the surface of the skin) to
record waveforms and blood pressure measurements.
These measurements are then compared to the
systolic blood pressure in the arm.
- pulse volume recording
(PVR) waveform analysis - a technique
used to calculate blood volume changes in the
legs using a recording device that displays
the results as a waveform.
- reactive hyperemia
test - a test similar to an ABI
or a treadmill test but used for people who
are unable to walk on a treadmill. While a person
is lying on his or her back, comparative blood
pressure measurements are taken on the thighs
and ankles to determine any decrease between
the two sites.
- segmental blood pressure
measurements - a means of comparing
blood pressure measurements using a Doppler
device in the upper thigh, above and below the
knee, at the ankle, and on the arm to determine
any constriction in blood flow.
There
are two main goals for treatment of peripheral
artery/vascular disease: control the symptoms
and halt the progression of the disease to lower
the risk of heart attack, stroke, and other complications.
Specific
treatment will be determined by your physician
based on:
- your age, overall health,
and medical history
- extent of the disease
- your signs and symptoms
- your tolerance for
specific medications, procedures, or therapies
- expectations for the
course of the disease
- your opinion or preference
Treatment
may include:
- lifestyle modifications
to control risk factors, including regular exercise,
proper nutrition, and smoking cessation
- aggressive treatment
of existing conditions that may aggravate PVD,
such as diabetes, hypertension, and hyperlipidemia
(elevated blood cholesterol)
- medications for improving
blood flow, such as antiplatelet agents (blood
thinners) and medications that relax the blood
vessel walls
- angioplasty - a catheter
(long hollow tube) is used to create a larger
opening in an artery to increase blood flow.
Angioplasty may be performed in many of the
arteries in the body. There are several types
of angioplasty procedures, including:
- balloon angioplasty
- a small balloon is inflated inside the
blocked artery to open the blocked area
- atherectomy - the
blocked area inside the artery is "shaved"
away by a tiny device on the end of a catheter
- laser angioplasty
- a laser used to "vaporize" the
blockage in the artery
- stent - a tiny
coil is expanded inside the blocked artery
to open the blocked area and is left in
place to keep the artery open
- vascular surgery -
a bypass graft using a blood vessel from another
part of the body or a tube made of synthetic
material is placed in the area of the blocked
or narrowed artery to reroute the blood flow
With
both angioplasty and vascular surgery, an angiogram
is often performed prior to the procedure.
Complications
of peripheral vascular disease most often occur
because of decreased or absent blood flow. Such
complications may include:
- amputation (loss of
a limb)
- heart attack
- poor wound healing
- restricted mobility
due to pain or discomfort with exertion
- severe pain in the
affected extremity
- stroke (three times
more likely in persons with PVD)
By following
an aggressive treatment plan for peripheral vascular
disease, complications such as these may be prevented.
Steps
to prevent PVD are primarily aimed at management
of the risk factors for PVD. A prevention program
for PVD may include:
- smoking cessation,
including avoidance of second hand smoke and
use of tobacco products
- dietary modifications
including reduced fat, cholesterol, and simple
carbohydrates (such as sweets), and increased
amounts of fruits and vegetables
- treatment of dyslipidemia
(high blood cholesterol levels) with medications
as determined by your physician
- weight reduction
- moderation in alcohol
intake
- medications as determined
by your physician to reduce your risk of blood
clot formation
- exercise plan of a
minimum of 30 minutes daily
- control of diabetes
mellitus
- control of hypertension
(high blood pressure)
A prevention
plan for PVD may also be used to prevent or lessen
the progress of PVD once it has been diagnosed.
Consult your physician for diagnosis and treatment.
Click
here to view the Online
Resources of Cardiovascular Disease
|
