Peripheral Vascular Disease Overview
Peripheral vascular disease, also called PVD, refers to any disease or disorder of the circulatory system outside of the brain and heart. The term can include any disorder that affects any blood vessels. It is, though, often used as a synonym for peripheral artery disease.
PVD is the most common disease of the arteries. The build-up of fatty material inside the vessels, a condition called atherosclerosis or hardening of the arteries, is what causes it. The build up is a gradual process. Over time, the artery becomes blocked, narrowed, or weakened.
When a blockage occurs in the arteries of the heart, it's called coronary heart disease or coronary artery disease. Most often, atherosclerosis is thought of in terms of its affect on arteries of the heart and of the brain. But athersclerosis can affect any other blood vessel throughout the body.
Blood vessels in the legs are the ones most often affected. Other arteries frequently affected include those that supply blood to the kidneys and those in the arms. When an artery is blocked or narrowed, the part of the body it supplies doesn't get enough oxygen. The condition is called ischemia. Ischemia can cause a variety of symptoms, depending on the organ or system that's affected.
Symptoms range from pain, cold feet, and bluish discoloration to stroke or gangrene. If the condition is not reversed, the affected body part is injured and eventually starts to die. It's important to find narrowed arteries before damage occurs.
Who Gets PVD
About 8 million people in the United States have PVD. It occurs mostly in people older than 60, affecting about 12% to 20% of people in that age group. It's also common among people with diabetes. Men are slightly more likely than women to have PVD. The disease is more common in smokers. The combination of diabetes and smoking almost always results in more severe disease.
PVD is the leading cause of disability among people older than 60 as well as those with diabetes. Up to 40% of the people with PVD don't have symptoms. Of those who do, many don't tell their health care providers.
People often think PVD is a normal part of aging and that nothing can be done about it. Others think the only solution is surgery. But surgery is only one of several effective treatments available. Treating PVD medically is the best way to prevent it from getting worse and protect against complications. This is especially true for people who have high blood pressure (hypertension) or diabetes, those with high fats or lipids in their blood, and those who smoke.
Causes of Peripheral Vascular Disease
The most common cause of PVD is peripheral artery disease, which is due to atherosclerosis. Fatty material builds up inside the arteries and mixes with calcium, scar tissue, and other substances. The mixture hardens slightly, forming plaques. These plaques block, narrow, or weaken the artery walls. Blood flowing through the arteries can be restricted or completely blocked.
Other causes of PVD include:
- Blood clots: A blood clot can block a blood vessel.
- Diabetes: The high blood sugar level present with diabetes can, over time, damage blood vessels. This makes them more likely to become narrow or to weaken. People with diabetes often also have high blood pressure and a high level of fats in the blood. Both conditions can accelerate the development of atherosclerosis.
- Inflammation of the arteries or arteritis: Arteritis can cause narrowing or weakening of the arteries. Some autoimmune conditions lead to vasculitis. The inflammation can affect not just arteries, but other organ systems too.
- Infection: The inflammation and scarring caused by infection can block, narrow, or weaken blood vessels. Both salmonellosis (infection with Salmonella bacteria) and syphilis are two infections traditionally known to infect and damage blood vessels.
- Structural defects: Defects in the structure of a blood vessel can cause narrowing. Most of these are acquired at birth, and the cause is unknown. Takayasu disease is a vascular disease that affects the upper vessels of the body. It occurs usually among females of Asian origin.
- Injury: Blood vessels can be injured in an accident such as a car wreck or a bad fall.
Risk factors for peripheral vascular disease include:
- Family history of heart disease, high blood pressure, high cholesterol, or stroke
- Older than 50 years
- Overweight or obesity
- Inactive (sedentary) lifestyle
- High blood pressure
- High cholesterol or LDL (the “bad cholesterol”), plus high triglycerides and low HDL (the “good cholesterol”)
People who have coronary heart disease or a history of heart attack or stroke generally also have an increased frequency of having PVD.
Peripheral Vascular Disease Symptoms
Only about 60% of the individuals with peripheral vascular disease have symptoms. Almost always, symptoms are caused by the leg muscles not getting enough blood. Whether you have symptoms depends partly on which artery is affected and to what extent blood flow is restricted.
The most common symptom of PVD in the legs is pain that comes and goes in one or both calves, thighs, or hips. The pain usually occurs while you are walking or climbing stairs and stops when you rest. It is usually a dull, cramping pain. It may also feel like a heaviness, tightness, or tiredness in the muscles of the legs.
When blood vessels in the legs are completely blocked, leg pain at night is typical.
Other symptoms of PVD include:
- Buttock pain
- Numbness, tingling, or weakness in the legs
- Burning or aching pain in the feet or toes while resting
- A sore on a leg or a foot that will not heal
- One or both legs or feet feeling cold or changing color (pale, bluish, dark reddish)
- Loss of hair on the legs
Having symptoms while at rest is a sign of more severe disease.
When to Seek Medical Care
When you have symptoms of peripheral vascular disease in a leg or a foot (or in an arm or a hand), see your health care provider for an evaluation. Generally, peripheral vascular disease is not an emergency. On the other hand, it should not be ignored.
- Medical evaluation of your symptoms and effective treatment, if indicated, may prevent further damage to your heart and blood vessels.
- It may prevent more drastic events such as a heart attack or stroke or loss of toes and feet.
If you have symptoms of peripheral vascular disease along with any of the following, call 911 for emergency medical care:
- Pain in the chest, upper back, neck, jaw, or shoulder
- Fainting or loss of consciousness
- Sudden numbness, weakness, or paralysis of the face, arm, or leg, especially on one side of the body
- Sudden confusion, trouble speaking or understanding
- Sudden trouble seeing in one or both eyes
- Sudden dizziness, difficulty walking, loss of balance or coordination
- Sudden severe headache with no known cause
Do not try to "wait it out" at home. Do not try to drive yourself. Call 911 right away for emergency medical transport.
Exams and Tests
Tests your doctor may use to identify or rule out PVD include:
Edinburgh Claudication Questionnaire:This is a test used by many medical professionals to diagnose peripheral artery disease. It is a series of 6 questions and a pain diagram. It is accurate at diagnosing PAD in people with symptoms up to about 90% of the time.
Ankle/brachial index (ABI): This is one of the most widely used tests for a person who has symptoms suggesting intermittent claudication -- pain associated with PVD that comes and goes as a result of narrowed blood vessels.
- This test compares the blood pressure in the arm (brachial) with the blood pressure in the legs.
- In a person with healthy blood vessels, the pressure should be higher in the legs than in the arms.
- An ABI above 0.90 is normal; 0.71-0.90 indicates mild PVD; 0.41-0.70 indicates moderate disease; and less than 0.40 indicates severe PVD.
Treadmill exercise test: If necessary, the ABI will be followed by a treadmill exercise test.
- Blood pressures in your arms and legs will be taken before and after exercise (walking on a treadmill, usually until you have symptoms).
- A significant drop in leg blood pressures and ABIs after exercise suggests PVD.
- Alternative tests are available if you are unable to walk on a treadmill.
- If the leg pulse can't be felt, the use of a portable Doppler flow probe will quickly reveal the absence or presence of an arterial flow.
To help locate blockages in your blood vessels, any of several tests, such as angiography, ultrasonography, or MRI (magnetic resonance imaging), can be used.
Angiography, or arteriography, is a type of X-ray. Angiography has for many years been considered the best test available and has been used to guide further treatment and surgery. However, imaging techniques, such as ultrasonography and MRI, are preferred more and more because they are less invasive and work just as well.
- Angiography uses a dye injected into the arteries to highlight blockages and narrowing of arteries. If you have diabetes or have kidney damage, the dye could cause further damage to your kidneys and, rarely, cause acute renal or kidney failure requiring dialysis.
- Certain treatments for blocked arteries, such as angioplasty, can be performed at the same time as the test. A specialist called an interventional radiologist or an invasive cardiologist can perform these treatments.
- With ultrasonograpy or MRI, angioplasty cannot be done.
Ultrasonography uses sound waves to find abnormalities.
- A handheld device that emits ultrasound waves is placed on the skin over the part of the body being tested. It is noninvasive and painless.
- You cannot hear or see the waves; they "bounce" off structures under your skin and give an accurate picture. Any abnormalities in the vessels or obstruction of blood flow can be seen.
MRI is a type of imaging study. Rather than radiation, MRI uses a magnetic field to obtain an image of internal structures. It gives a very accurate and detailed image of blood vessels. This technique is also noninvasive.
Several other tests are used under certain circumstances. Your health care provider can explain why he or she recommends certain tests.
Peripheral Vascular Disease Treatment
Treatment depends on the underlying cause of your disease, the severity of your condition, and your overall health.
Self-Care at Home
Your health care provider will recommend ways that you can reduce your risk factors for atherosclerosis and PVD. Not all risk factors can be changed, but most can be reduced. Reducing these risk factors can not only prevent your disease from getting worse but also may actually reverse your symptoms.
- Quit smoking: Quitting smoking reduces symptoms and lowers your chance of having your peripheral artery disease (and arteries elsewhere) get worse.
- Get active: Regular exercise, such as walking, can often reduce symptoms and increase the distance you can walk without symptoms.
- Eat nutritious, low-fat foods and avoid foods high in cholesterol.
- Maintain a healthy weight.
- Follow your health care provider's recommendations for controlling high blood pressure and high cholesterol.
- If you have diabetes, follow your health care provider's recommendations for controlling your blood sugar and taking care of your feet. Injuries to the skin could lead to skin breakdown, gangrene, and loss of toes if blood flow is impaired.
Percutaneous (through the skin) balloon angioplasty, or just "angioplasty," is a technique for enlarging an artery that is blocked or narrowed without surgery.
- A diagnostic angiogram is done first to locate the blockage or narrowing and determine the severity. That's because minor blockages, for instance, can often be treated with medicine. If the obstruction is significant, especially in a larger artery, angioplasty may be reasonable.
- The angioplasty is perfomed through a thin tube called a catheter inserted with a needle into the affected artery. It has a tiny balloon attached to the end. The balloon is inflated, pushing aside the plaque and widening the artery so that it no longer restricts blood flow.
- The balloon is then deflated and removed from the artery.
Stenting is a technique for arteries that are severely blocked or begin to close up again after angioplasty.
- The majority of peripheral vascular lesions can be managed by placement of a stent, a small metal mesh sleeve that is fixed inside the narrowed artery.
- Stenting and angioplasty are very useful if the obstructive lesions are localized and involve a small portion of the vessel. Generally, the stent is placed during or after angioplasty.
- The stent holds the artery open. Eventually, new tissue grows over the stent.
- There are two types of stents that can be used: A bare metal stent was the initial approach. However, development of fibrous scar tissue inside the stent can lead to obstruction coming back. The problem is being addressed with a new generation of "drug-eluting" stents. A drug is attached to the metal sleeve that dissolves into the blood and prevents or slows the development of scar tissue.
Atherectomy is removal of an atherosclerotic plaque. A tiny cutting blade is inserted into the artery to cut the plaque away.
Whether medication is a good choice for you depends on the underlying cause of your PVD. Medications used to treat PVD and intermittent claudication include those that aim to lower the risk and progression of atherosclerosis throughout the body. That includes medicines that help you stop smoking, lower blood pressure, lower cholesterol, and optimize blood sugar if you have diabetes.
Several medications are available to treat the symptoms of intermittent claudication -- pain as a result of narrowed or blocked blood vessels:
- Cilostazol (Pletal): This drug keeps platelets from clumping together. This clumping promotes formation of clots and slows down blood flow. The drug also helps dilate, or expand, the blood vessels, encouraging the flow of blood.
- Antiplatelet agents include aspirin, aspirin plus dipyridamole , ticlopidine, and clopidogrel. They prevent clots from forming by keeping blood cells and platelets from clumping together. They may be given to help prevent heart attack and stroke.
- Pentoxifylline (Trental): This drug is believed to improve blood flow by making red blood cells more flexible and making the platelets less sticky. Recent studies have questioned the effectiveness of pentoxifylline.
Medications to help prevent the development and progression of atherosclerosis such as cholesterol lowering medicines are also very important.
When the obstructive lesions are long and involve most of the vessel, surgery may be the best alternative. The most widely used operation for a blocked or damaged artery is called a bypass. This is similar to the artery bypass operation done on the heart.
A piece of vein, harvested from another part of your body, or a piece of synthetic artery is used to bypass or detour the obstructed segment of disease, therefore restoring blood flow to the downstream or distal portion of the artery.
Surgery is required less often today, as better preventative anti-atherosclerotic medications and techniques have become available for treating blocked or damaged arteries. With modern treatments, surgery is required only for very severe atherosclerosis that's unresponsive to medications and angioplasty.
Follow the recommendations of your health care provider for risk factor reduction. If he or she recommends medication, take the medication as directed. Report changes in your symptoms and any side effects you experience.
The best way to prevent peripheral vascular disease is to reduce your risk factors. You cannot do anything about some of the risk factors, such as age and family history. Other risk factors are under your control.
- Do not smoke.
- Eat nutritious, low-fat foods; avoid foods high in cholesterol.
- Maintain a healthy weight.
- Engage in moderately strenuous physical activity for at least 30 minutes a day. At least walk briskly for 20-30 minutes daily.
- Control high blood pressure.
- Lower high cholesterol (especially LDL cholesterol or the “bad cholesterol”) and high triglyceride levels. Raise HDL or “the good cholesterol.” If exercise fails to lower your cholesterol, certain medications (statin drugs) can be taken to decrease the bad cholesterol.
- If you have diabetes, control your blood sugar level and take scrupulous care of your feet. Ask your doctor what your HbA1C is, a measure of how well your blood sugar is controlled; it should be less than 7.0 for most people. If it is greater than 8.0, the sugar is not controlled, and your risk of blood vessel complications (eyes, heart, brain, kidneys, legs) escalates.
Smoking is a very strong risk factor for developing peripheral vascular disease and can significantly worsen the disease, especially in diabetics. Quitting smoking can often reduce the symptoms of PVD and lower your chance that the disease will get worse.
If untreated, PVD can develop complications that can include:
- Permanent numbness, tingling, or weakness in legs or feet.
- Permanent burning or aching pain in legs or feet.
- Gangrene: This is a very serious condition. It is the result of a leg or foot or other body part not getting enough blood. The tissues die and begin to decay. The only treatment is amputation of the affected body part.
People with peripheral vascular disease are at higher-than-normal risk of heart attack and stroke.