Transcript document

PERIPHERAL VASCULAR
DISEASE
Presented by Jill Kerkman
Pathophysiology
 Form of atherosclerosis
 Progressive disease
May occur suddenly if an embolism occurs
or when a blood clot rapidly develops in a
blood vessel restricted by an
atherosclerotic plaque, and the blood flow
is quickly cut off.
 PVD is a generic term that encompasses
vascular insufficiencies such as
arteriosclerosis, arterial stenosis, Raynaud’s
phenomenon.
 Peripheral arteriosclerosis is common in the
elderly and is often associated with
hypertension and hyperlipidemia.
PVD is frequently observed in patients with
CAD, diabetes, and a long-term history of
smoking.
Two types of PVD
 Functional
Doesn’t have an organic cause.
Doesn’t involve defects in blood vessels’
structure, usually short-term effects and
come and go.
Ex: Raynaud’s disease.
 Organic
Caused by structural changes in the blood
vessels, such as inflammation.
Ex: Peripheral artery disease, caused by
fatty buildups in arteries.
How Common is PVD?
 Affects about 1 in 20 people over the age of
50, or 8 million people in the US.
 PVD is only diagnosed in 50% of the
population.
 Symptomatic PVD carries at least a 30% risk
of death within 5 years and almost 50% within
10 years, primarily due to MI (60%) or stroke
(12%).
Symptoms of PVD
 Leg or hip pain during walking (intermittent
claudication).
 The pain stops when you rest.
 Numbness, tingling or weakness in the legs.
 Burning or aching pain in feet or toes when
resting.
 Sore on leg or foot that won’t heal.
 Cold legs or feet.
 Color change in skin of legs or feet.
 Loss of hair on legs.
The 5 P’s
 Peripheral signs of PVD are the classic 5 P’s
Pulselessness
Paralysis
Paraesthesia
Pain
Pallor
 Paralysis and paraesthesia suggest limbthreatening ischemia and mandate prompt
evaluation and consultation.
 Advanced PVD may manifest as mottling in a
“fishnet pattern”, pulselessness, numbness,
or cyanosis. Paralysis may follow, and the
extremity may become cold; gangrene
eventaully may be seen. Poorly healing
injuries or ulcers in the extremities help
provide evidence of preexisting PVD.
Who is at risk for PVD?
 Over the age of 50
 Smokers
 Diabetics
 Overweight (especially with syndrome X or
hyperinsulinism)
 Male sex
 Sedentary people
 People who have hypertension or high
cholesterol
 Family history of heart or vascular disease
Pain Scale
 A subjective grading scale for PVD pain is as
follows:
Grade 1: Definite discomfort or pain, but only
of initial or modest levels (established, but
minimal).
Grade 2: Moderate discomfort or pain from
which the patient’s attention can be diverted,
for example by conversation.
Grade 3: Intense pain (short of Grade 4) from
which the patient’s attention cannot be
diverted.
Grade 4: Excruciating and unbearable pain.
How is PVD Diagnosed?
 Ankle-Brachial Index Test (ABI)
The blood pressure in your arms and
ankles is checked using a regular blood
pressure cuff and a special ultrasound
stethoscope called a Doppler.
The pressure in your ankle is compared to
the pressure in your arm to determine how
well your blood is flowing.
The index is determined by dividing ankle
systolic BP by arm systolic BP.
ABI
 Measurements are usually taken at rest and
after standardized treadmill exercise (i.e.. For 5
min. at 2mph, 12%).
 A normal resting ABI is 1 or 1.1.
 An index of 0.9 or less indicates the presence
of obstructive disease.
 0.5 or less suggests multiple-level arterial
disease.
 An ABI of less than 0.26 indicates severe, limbthreatening arterial compromise.
Duplex Ultrasonography and
Doppler Color-Flow Imaging
 Technical advances in ultrasonography have
allowed reproducible measurements of blood
vessels and blood flow as well as
standardization of criteria for assessment of
PVD.
 Doppler color-flow imaging are useful in
localizing diseased segments, and spectral
imaging can assess lesion severity.
Magnetic Resonance Imaging
and Angiography
 Useful in evaluating arterial dissection and
characterizing vessel-wall morphology
(including hematoma or thrombus).
 Computed Tomography (CT) Angiography
Treatment for PVD
 Severe lower extremity PVD is treated initially
with cardiovascular disease risk factor
modification:
Exercise training
Medication
Diet
Stop Smoking
Interventional Radiology
Surgery
Gene-Based Therapy
Exercise
 Research has shown that regular exercise is
the most consistently effective treatment for
PVD.
 Patients who have taken part in a regular
exercise program for at least 3 months have
seen substantial increases in the distances
they are able to walk without experiencing
painful symptoms.
Exercise Prescription
 Training Intensity
Initial
• Set by result of peak treadmill.
• Starting exercise work load brings on
claudication pain.
Subsequent
• Speed or grade increased if patient
walks > 10 minutes.
• Grade increased first if speed > 2 mph.
• Speed increased first if < 2 mph.
Exercise Prescription
 Duration
Initial
• 35 minutes (intermittent walking)
Subsequent
• Add 5 minutes every session until 50
minutes (intermittent walking) is possible
Exercise Prescription
 Frequency
3-5 times per week.
 Specificity of Activity
Treadmill walking is the recommended
exercise.
Stop Smoking
 On average, smokers are diagnosed with
PVD as much as 10 years earlier than nonsmokers.
 Stopping smoking now is the single most
important thing you can do to halt the
progression of PVD or prevent it in the future.
Medications
 Drugs that lower cholesterol or control high
blood pressure.
 Decrease blood viscosity.
Trental, Persantine, or Coumadin
 Antiplatlet agents: their primary long-term
benefit is reduction in cardiovascular events
and mortality.
ASA doses of 75 to 325mg QD have
shown protective benefits.
Ticlid and Plavix also have shown promise
in disease prevention and in therapy after
vascular intervention.
Interventional Radiology
Treatments
 Angioplasty
 Stents
 Thrombolytic Therapy
 Stent-Grafts
Gene-Based Therapy
 The field of molecular genetics has provided
new understanding of vascular physiology and
pathology and has opened exciting frontiers in
the treatment of PVD.
 Direct gene transfer by intramuscular injection
of DNA encoded with vascular growth factors
has resulted in growth of new vessels and
collateral circulation in chronically occluded
lower extremity arterial vessels.
Surgical Treatments for PVD
 Thrombectomy
 Bypass Grafts
Aneurysms
 Most common lethal peripheral vascular
abnormality.
An artery whose diameter is 1.5 times the
normal.
 Aortic aneurysms are caused by weakening of
the artery walls due to atherosclerosis. The
weakened walls balloon out, forming an
aneurysm.
 When blood pumps from the heart through the
aorta, it places pressure on the aneurysm
walls. Over time, the aneurysm can get bigger
and bigger, until eventually it may rupture.
Aortoiliac Occlusive Disease
 Typically involves the distal abdominal aorta
as well as the common and external iliac
arteries.
 Aortobifemoral bypass with a prosthetic graft
has been the traditional treatment of choice
for aortoiliac occlusive disease since the
1960’s.
 The operative morbidity and mortality are in
the 2% range, and long-term patency
exceeds 90%.
Superficial Femoral Occlusive
Disease
 Presents with symptoms of claudication of the
calf and sole of the foot.
Usually improves as collateral circulation
develops.
 Best treatment initially is antiplatelet therapy
in combination with a vigorous exercise
program.
Tibial Artery Disease
 Distal atherosclerotic disease involving the
tibioperoneal trunk and the tibial vessels is
the most difficult to treat and leads to the
greatest morbidity and tissue loss.
 ABI is typically less than 0.4 before rest pain
develops, and any value less than 0.3 almost
always results in ischemic tissue loss.
Upper Extremity Disease
 Atherosclerotic disease involving the arms is
almost always limited to the larger proximal
vessels and rarely involves the brachial,
radial, or ulnar arteries.
 Although these patients have no symptoms,
they can have a large discrepancy in BP
between the left and right arms.
Always prudent to measure BP in both
arms.
Thrombosis
 A thrombus, or blood clot, within a blood
vessel.
 Normally, a blood clot forms to prevent
bleeding but a thrombus is an abnormal blood
clot in the vessel when it is not even
punctured.
 The clotting process may be encouraged by
the buildup of fatty acids on the vessel walls.
 Thrombosis in the vein may cause pain and
swelling.
Deep Venous Thrombosis
 A blood clot in a deep vein.
 May form on the valves within the vein, and
may subsequently increase in size to totally
occlude the vein.
 Sometimes parts of the clot may break off
and travel in the bloodstream to the lungs and
cause serious health problems (pulmonary
embolism).
 DVT is perhaps the most dangerous problem.
 Patients with DVT have a 30 to 40% risk of
recurrence later in life.
Phlebitis
 Inflammation of the leg veins.
 Two types:
Inflammation of the veins on the surface of
the leg (more common).
Inflammation of the deep veins of the leg.
 Phlebitis is caused by an infection or injury.
 Can cause a blood clot to form and this clot
can then embolize and result in pulmonary
embolism. This is the worst thing that can
happen if you have phlebitis.
Pulmonary Embolism
 An embolus is a clot or any other piece of
material that is carried around in the blood.
 Pulmonary embolism is where the embolus
gets stuck in a vessel going to the lungs.
 The only way a clot can go to a vessel in the
lungs is if it passes through the heart and is
pumped out of the pulmonary artery.
 So, the closer the clot is to the heart, the
more likely to get a pulmonary embolism.
Varicose Veins
 Caused because either the blood flow is too slow
making the vein pile up with blood or the valve in
the vein is not working well so the blood falls
down due to gravity and piles up in the veins of
the legs.
 Sclerotherapy: Irritant chemical is injected into
the veins, causing them to scar and seal off. This
“detours” the blood to nearby healthier veins.
 Stripping: Procedure used to remove larger
varicose veins. Parts of the vein can be removed
or tied off, or the entire vein can be removed.
 Surgery continues to play an important role in
the management of peripheral vascular
disease.
 Revascularization procedures provide
excellent outcomes for many patients at risk
for loss of a limb or seriously impaired quality
of life.
 Although endovascular techniques are now
being used for managing many vascular
problems, the traditional surgical approaches
still offer well-documented benefits.