Friday, October 09, 2009

말초동맥질환 - 14. PAD(Peripheral Arterial Disease)'s Treatment

14. PAD(Peripheral Arterial Disease)'s Treatment

Treatment options vary and depend on the overall health of the patient and the severity of the diagnosis. The physician should provide the patient with adequate information to help understand all options. The majority of intermittent claudication cases are treated without surgery. Multiple long term studies following a large number of patients with claudication demonstrated that only 1 out of 4 developed worsening symptoms. It also found that only 1 out of 20 patients would require an amputation. A treatment plan involves lifestyle changes and one or more of the following:

▣ Exercise Therapy
Lifestyle Modifications
Medication
Diet
Smoking Cessation
Diabetes management
Blood pressure management
Foot Care
Endovascular Therapy(Intervention; Angioplasty and Stenting)
Vascular Surgery

1. Exercise Therapy

Exercise therapy for intermittent claudication is an individualized exercise prescription (or plan) designed to restore health and prevent further disease. The prescription is written by a doctor or rehabilitation specialist such as a clinical exercise physiologist, physical therapist, or nurse. It takes into account your current medical condition and provides advice for what type of exercise to perform, how hard to exercise, how long, and how many times per week. Therapeutic exercise for individuals with claudication is usually prescribed as sessions that occur three or more times per week, an hour or more per session, for three months.

This requires self-motivation and real time commitment, but such commitment is associated with powerful benefits.

Exercise for claudication is best done in a supervised setting such as a cardiac rehabilitation program and has been shown to relieve leg pain during walking, increase walking distance and time, and improve overall cardiovascular health. It also helps decrease any further build up of cholesterol, assists in weight loss efforts, and helps maintain healthy circulation.

Persons with intermittent claudication have about one half the walking ability of healthy persons of the same age. Some individuals with claudication can walk less than one block before they must stop and rest. Reduced physical activity further aggravates PAD as well as other medical problems such as high blood pressure, obesity, and diabetes.

A program of supervised exercise training is at the cornerstone of treatment for reducing claudication symptoms. The main activity to be performed is walking. A program of exercise can be expected to increase the speed, distance, and duration of walking before symptoms occur. The benefits from exercise occur gradually and become evident over 1-2 months, and continue to increase for 3-6 months and longer. An important goal of rehabilitation therapy for an individual with PAD is to relieve the claudication symptoms, restore exercise capacity, and to reduce cardiovascular disease risk.

Exercise for claudication is different than exercise advised for many other conditions since exertion to the point of leg pain is required for maximum benefits. The insufficient blood supply that causes the leg pain during walking is also the stimulus for many of the favorable changes that lead to the ability to eventually walk longer. For this reason, exercises that use muscles that do not result in claudication pain are not beneficial for improving claudication symptoms. For example, working out with the arms, would not produce leg pain. Bicycling, which primarily uses the upper thigh muscles, would not typically produce claudication pain of the calf muscle and is not as effective an exercise for improving claudication.

Because PAD is a form of atherosclerosis, individuals with this condition are also at risk for cardiovascular disease and stroke. Therefore, it is important for individuals who plan to participate in a claudication exercise program to see their physician before starting an exercise program to assure that they can safely participate. The physician will review your cardiovascular health history, perform a thorough physical examination and a resting electrocardiogram, and may recommend that you undergo an exercice stress test on a treadmill.

During the treadmill test, the electrocardiogram, heart rate, and blood pressure will be monitored.  As well, the time walked until the onset of claudication and the total amount of time that you can walk on the treadmill will be recorded. In addition to measurement of blood pressure in the arms, the blood pressure in the legs may be recorded before and after the walking portion of the treadmill test. All of this information is used to evaluate your walking ability and the condition of your heart. Based on the results of the treadmill test, a change in medications might be needed or additional testing may be recommended. The treadmill test also provides information that will be used to create an exercise prescription that is tailored to your individual needs.

An exercise workout should be done on a treadmill under medical supervision. If a treadmill-based program is not available, exercise can be effectively performed on a track. Exercise should be performed at least three or more times a week. The starting workload of the treadmill is set at a level that will bring on usual claudication symptoms within 3 to 5 minutes.

Walking continues at this workload until the pain is of moderate severity. On a scale from 1-5, where 1 is mild pain and 5 is very severe pain, a pain level of 3 is the target. After 8 to 10 minutes, there should be a brief period of rest to allow the symptoms to resolve. The exercise-rest-exercise cycle is repeated several times so that a total of 35 minutes of walking is achieved in the first few sessions of the program.

Exercise time should be gradually increased by a few minutes each workout until a total of 50 minutes of walking can be achieved. A good sign that progress is occurring is when the first 8 to 10 minutes of walking can be completed with much less pain. This is also a sign that the workload should be increased so that a moderate level of pain always occurs during walking.

A very important precaution is that while moderate pain in the leg is expected and desirable, pain that occurs elsewhere in the body is an indication to stop.

For example, pain that occurs in the chest, arms, neck, or throat could be a sign of insufficient blood flow to the heart. This type of pain should be reported immediately to the medical professional supervising the exercise session and to your personal physician.

Besides improving the ability to walk, exercise has numerous benefits that also improve the overall health of persons with PAD. Exercise helps maintain an ideal body weight, lowers blood pressure, increases HDL cholesterol (“good” cholesterol), lowers blood glucose (sugar) in persons with diabetes, reduces triglycerides, and improves the overall condition of the heart and blood vessels.

2. Lifestyle Modifications

According to medical studies, plaque buildup in arterial walls can be decreased (and even reversed) if you change your lifestyle. In other words, if you can make some simple changes in your diet, start exercising, and quit smoking, for example, you might be able to avoid drug therapy or surgery. Changing your lifestyle works, and it's easier than the alternatives.

If you can make the changes your physician suggests, you'll start seeing the effects within six months. But the benefits only last as long as you keep it up -- if you start smoking again, for example, you'll end up back where you started. Look at the changes you make as a new way to live, not as temporary "diet" or brief, healthy binge.

Yes. If you are smoking in any way, shape or form, your symptoms will not go away and treatment won't work. The medications your doctor gives you won't work if you are smoking. Even one or two cigarettes a day, or low nicotine cigarettes, cause damage. You have to quit, not cut back. Every year, smoking causes 350,000 deaths. Most of the deaths are caused by heart attacks. Tobacco use of any type hurts your heart and blood vessels in two major ways. First, nicotine narrows blood vessels. Second, the carbon monoxide in smoke damages the cells that line arteries so they get hard -- it's difficult for blood to move through narrow, inflexible passages.

People often find it easiest to quit smoking if they use a combination of things. Often, a combination of methods is easiest. For example, 85% of smokers who use nicotine patches in combination with group programs quit.

There are many alternatives, including nicotine gum, patches and prescription medications to help curb nicotine cravings. Many people fear they will gain weight after quitting. Surprisingly, the average weight gain after one year of quitting is only 6 pounds. The health risks of smoking are greater than this amount of weight gain. Facing your addiction openly and honestly is the basis for success.

Your physician might give you medicine or suggest changes in your diet to lower cholesterol. Cholesterol levels can go up or down based on the amount of saturated fat and cholesterol in the food you eat, your weight, and the amount of exercise you do. To some extent, cholesterol levels also are hereditary -- if your parents had high cholesterol, you are more likely to have it too.

Inherited or not, you can lower your cholesterol levels by reducing or eliminating meats high in saturated fat, whole dairy products (this includes cheese!), coconut and palm oils (these show up in many store-bought cookies, cakes, and crackers.

Changing lifelong eating habits can be hard, but following a physician's diet recommendations can be a significant component to success.

When untreated, high blood pressure increases the workload on the heart and creates undue stress on the arteries. Be serious about taking your medicine to avoid risk of stroke, heart attack and congestive heart failure. A diet low in salts and saturated fats will help, too.

Remember that lifestyle behavior change should be gradual and will come in stages. Motivation for change is different for each person. When you feel discouraged, try these suggestions:

♣ Review your goals to see if they are realistic
Keep a chart of your progress
Focus on what you have learned
Find support from others – find an exercise partner

Seek support from your health care professional or mental health counselor.

3. Foot Care

In cases where the blood flow to the legs causes injuries to the feet and toes, serious infection, sores or gangrene may result. In these instances proper foot care is essential:

♣ consistent checking for sores, redness, swelling or drainage
proper and comfortable fitting shoes
maintenance of good foot hygiene (toenails cut straight across proper medicaltreatment for corns, calluses and bunions)

4. Endovascular Therapy (Intervention; Angioplasty and Stenting)

Once the diagnosis of peripheral arterial disease has been established, one of the options for treatment is endovascular therapy.

In an effort to improve blood flow to a leg, one of two methods may be used:

Stent: A medical device made of an expandable wire mesh tube that is inserted into an artery narrowed by plaque. Once inserted it can expand and hold open the artery, allowing the blood to flow through. For further info on stents, go here.

Angioplasty: Using tools that allow a physician to work inside the artery, a tiny balloon is placed directly in the narrowing.  Liquid is put in the balloon, the balloon expands, and opens the blockage.  The balloon is then deflated and removed.

Surgery: Re-routing of blood from above an area of blockage to below the blockage, using either a piece of synthetic material, or the patient's own vein.

Once the decision is made to perform angioplasty, the procedure is scheduled. Patients are instructed on which medications they should take on the morning of the procedure. Other than some morning medications, no food or liquid is allowed.

 
The patient is brought to the angiographic suite, and is asked to lay down on a table. A sedative is typically prescribed to lessen any discomfort.

Then, using a tiny, flexible tube, called a catheter, and the X-Rays, the doctor takes pictures of the arteries of interest, injecting a small amount of a liquid, called contrast dye, that generates a road map of the areas of blockage.

Once these pictures have been reviewed by the doctor, and the decision has been made that an angioplasty can be performed, through the same location in the groin, the balloon catheter is placed into the narrowed artery, liquid is used to inflate the balloon, and the artery is opened.

Often a metallic mesh scaffolding device, known as a stent, is fitted onto the balloon, and when the balloon is inflated and then deflated, the stent is embedded into the wall of the artery and is left in place permanently.

Occasionally, the patient may feel some pressure in the area of the artery as the balloon is being inflated. Always report any discomfort to your physician.

After the procedure has been completed, the tube in the groin will be removed. In certain instances, the doctor will choose a closure device which seals the hole in the artery, preventing it from bleeding.

In other circumstances, the doctor, nurse, or technologist, will hold steady pressure on the groin for a few minutes to prevent bleeding, and allow the hole to seal. In either situation, the patient will need to lay flat for a period of time. The recovery period is generally a few hours during which the patient will be kept on bedrest and will be required to keep the site used for access still.

Although the procedure is considered safe and of relatively low risk, there are certain problems which may develop. Always ask the physician if there are concerns.

♣ Bleeding from the groin hole this is generally minimal, although in uncommon situations,there may be need for a procedure to stop the bleeding.

♣ Problems with the kidney function as a result of the contrast dye this is usually a temporary issue, however, uncommon cases may result in permanent kidney damage.

Artery tearing this is very unusual, yet may require emergency surgery.

This is an effective procedure for many situations. The major limitation is re-narrowing of the angioplasty site. Generally, the larger the artery, the longer the artery stays open after angioplasty.

With that in mind, the iliac arteries which arise from the aorta at the level of the belly button tend to last the longest. Arteries below the groin, and worse yet, below the knee, tend to re-narrow faster.

5. Vascular Surgery

There are many types of highly successful procedures that can help improve circulation, increase walking distance, heal foot ulcers and prevent amputation. These are typically recommended after a thorough evaluation of the vascular lab results combined with the patient's age and health history. The primary care physician will refer the patient to a vascular surgeon or interventional radiologist. The advantages, risk of complications, and recovery time should be discussed in detail with all medical staff involved.

When vascular surgery or interventions are under consideration, a procedure called an arteriogram is normally performed. This helps the surgeon visually pinpoint the exact blockages in the arteries in the leg. An x-ray is obtained by injecting dye through a needle or small catheter inserted into an artery. Some patients experience a brief, hot, burning-like sensation when the dye is injected. An X-ray map of the arteries and sites of blockage is produced.

Surgical therapy has been used to treat patients with PAD for many decades. Because of such extensive experience, vascular surgeons have learned a tremendous amount about the likelihood of success for individual operations, the durability of these procedures, and the type of individuals most likely to benefit from surgery. In addition, vascular surgeons fairly well understand the risks and consequences of these procedures.

It is important to understand that surgery does not cure the patient of PAD. Surgery merely provides more blood flow to the leg involved, but the PAD remains.

▣ Endarterectomy
Bypass grafting

5-1. Endarterectomy Surgical Procedures

Endarterectomy for PAD works best for narrow areas or complete blockages in the body that are in the pelvis (iliac arteries) or groin (femoral arteries) and are short in length.

The surgeon actually opens the artery along its length and uses tools to peel away the diseased area of the artery.

The surgeon will then close the artery with a patch to make the operated artery wider and less likely to narrow from scarring in the months following the surgery.

This procedure is almost always limited to just the groin area, because angioplasty and stenting are preferred treatment for the pelvis area.

Since the surgeon must open the artery along its length, the incision (part of the leg cut open with the knife) must be fairly large to allow for this.

This technique does not work very well for smaller arteries farther down the leg and is not often used in those areas.

5-2. Bypass grafting

Bypass grafting is the rerouting the blood from above an obstruction in the artery to below an obstruction.

Bypass is the most common surgical technique used to treat PAD.

Bypasses have names that describe the artery above the blockage and the artery below the blockage. Examples would be:

♣ aortobifemoral (blood routed from the abdominal aortic artery to both femoral arteries)
♣ femoropopliteal (blood routed from thefemoral to the popliteal artery)
♣ femorotibial (blood routed from thefemoral to a tibial artery), etc.

Since bypass grafting is a rerouting of the blood flow, a tube (graft or conduit) is required to carry the blood.

Sometimes the patient’s veins are used.

The type of conduit used depends on the location of the bypass graft. For bypasses in the pelvis (aortobifemoral) artificial material works best because these are large arteries requiring large conduits.

There are no readily available veins of the correct size to use. For bypasses down the leg, artificial conduit is used as long as the bypass graft does not have to cross the knee.

However, bypasses below the knee work best with the patient’s own vein, preferably the saphenous vein (the same vein from the inner leg that heart surgeons use to bypass the heart blood vessels during open heart surgery).

5-2-1. What other things do I need to know about bypass surgery?

1) Placing a bypass permanently changes the artery structure of the leg. That often means that if the bypass clots off, the patient may have worse symptoms than before it was placed. This could include symptoms that become so severe that without another bypass, the patient may lose their leg and require an amputation.

2) All bypasses have an expected patency (time while the bypass remains open and continues to function) that is measured from 5 to 15 years. Bypasses in the pelvis usually have the best results. In general, the farther down the leg a surgeon has to go to bypass an obstruction, the shorter the patency of the bypass.

3) Bypass operations in older patients with PAD can pose more risks in addition to clotting off and not functioning. These risks include death from various causes, most often heart attack (usually occurs in the days following the operation). In general, the risk of death is one in twenty, although younger patients have less risk and older patients may have greater risk.

4) Leg complications are more common, including infections and breakdown of incisions. The vast majority of these will eventually heal, but it may take weeks or months. Many patients will have swelling of the operated leg, which can be severe. The swelling often gets better with time, but mild permanent swelling is common.

5-2-2. What type of follow-up care will I need?

Bypasses have a much better chance of long-term success if the surgeon continues to supervise the patient periodically in a clinic. The bypass must be monitored with physical examinations and ultrasound to make sure it does not narrow in spots -- narrowing can occur without any symptoms. If the surgeon is able to detect this narrowing, it can usually be repaired with either balloon techniques or a small surgery. If it is allowed to progress and blocks off the bypass completely, then the patient may lose their leg or require a large operation.

5-2-3. What can I do to stay healthy?

Lifestyle changes that help you manage your leg artery disease include:

♣ Managing diabetes by maintaining healthy blood sugar levels;
♣ Lowering high cholesterol;
♣ Lowering high blood pressure;
♣ Quitting smoking;
♣ Eating foods low in saturated fats and calories;
♣ Maintaining your ideal body weight;
♣ Exercising and walking regularly, for instance walking at least 30 minutes 3 times each week.