Vascular surgery is the treatment of surgery on diagnosed patients with diseases of the arterial, venous, and lymphatic systems (excluding the intracranial and coronary arteries).
Vascular surgery is indicated when a patient has vascular disease that cannot be treated by less invasive, nonsurgical treatments. The purpose of vascular surgery is to treat vascular diseases, which are diseases of the arteries and veins. Arterial disease is a condition in which blood clots, arteriosclerosis, and other vascular conditions occur in the arteries. Venous disease involves problems that occur in the veins. Some vascular conditions occur only in arteries, others occur only in the veins, and some affect both veins and arteries.
As people age, vascular diseases are very common. Since they rarely cause symptoms in the early stages, many people do not realize that they suffer from these diseases. Of the eight million people in the United States who may have peripheral vascular disease (PVD), a large percentage are males. In the majority of cases, the blockage is caused by one or more blood clots that travel to the lungs from another part of the body. Factors that increase the chances of vascular disease include:
- increasing age (which results in a loss of elasticity in the veins and their valves)
- a family history of heart or vascular disease
- illness or injury
- prolonged periods of inactivity sitting, standing, or bed rest
- hypertension, diabetes, high cholesterol, or other conditions that affect the health of the cardiovascular system
- lack of exercise
Vascular surgery involves techniques relating to endovascular surgeries including: balloon angioplasty and/or stenting, aortic and peripheral vascular endovascular stent/graft placement, thrombolysis, and other adjuncts for vascular reconstruction.
The vascular system is the network of blood vessels that circulate blood to and from the heart and lungs. The circulatory system (made up of the heart, arteries, veins, capillaries, and the circulating blood) provides nourishment to the body’s cells and removes their waste. The arteries carry oxygenated blood from the heart to the cells. The veins return the blood from the cells back to the lungs for reoxygenation and recirculation by the heart. The aorta is the largest artery leaving the heart; it then subdivides into smaller arteries going to every part of the body. The arteries, as they narrow, are connected to smaller vessels called capillaries. In these capillaries, oxygen and nutrients are released from the blood into the cells, and cellular wastes are collected for the return trip. The capillaries then connect to veins, which return the blood back to the heart.
The aorta stems from the heart, arches upward, and then continues down through the chest (thorax) and the abdomen. The iliac arteries, which branch out from the aorta, provide blood to the pelvis and legs. The thoracic section of the aorta supplies blood to the upper body, as it continues through the chest. The abdominal section of the aorta, which supplies blood to the lower body, continues through the abdomen.
Vascular diseases are usually caused by conditions that clog or weaken blood vessels, or damage valves that control the flow of blood in and out of the veins, thus robbing them of vital blood nutrients and oxygen. A few common diseases affecting the arteries are peripheral vascular disease (PVD), carotid artery disease, and aortic aneurysms (AAA).
Surgery is used to treat specific diseased arteries, such as atherosclerosis, to help prevent strokes or heart attacks, improve or relieve angina or hypertension, remove aneurysms, improve claudication, and save legs that would otherwise have to be amputated. The choices involve repairing the artery, bypassing it, or replacing it.
As people age, atherosclerosis, commonly called hardening of the arteries, occurs with the constant passage of blood through the arteries. It can take on a number of forms, of which atherosclerosis (hardening of the innermost portion) is the most common. This occurs when fatty material containing cholesterol or calcium (plaque) is deposited on the innermost layer of the artery. This causes a narrowing of the inside diameter of the blood vessel. Eventually, the artery becomes so narrow that a blood clot (thrombus) forms, and blocks blood flow to an entire portion of the body. This condition is called PVD or peripheral arterial disease. In another form of atherosclerosis, a rough area or ulcer forms in the diseased interior of the artery. Blood clots then tend to develop on this ulcer, break off, and travel further along, forming a blockage where the arteries get narrower. A blockage resulting from a clot formed elsewhere in the body is called an embolism.
People who have few areas affected by PVD may be treated with angioplasty by opening up the blood vessel with a balloon placed on the end of a catheter. A stent is often used with angioplasty to help keep the artery open. The type of surgery used to treat PVD is based upon the size and location of the damaged artery. The following are surgery techniques used for severe PVD:
- Bypass surgery is preferred for people who have many areas of blockage or a long, continuous blockage.
- Aortobifemoral bypass is used for PVD affecting the major abdominal artery (aorta) and the large arteries that branch off of it.
- In a technique called thromboendarterectomy, the inner diseased layers of the artery are removed, leaving the relatively normal outer coats of the artery.
- Resection involves a technique to remove a diseased artery following an aneurysm; a bypass is created with a synthetic graft.
- In a bypass graft, a vein graft from another part of the body or a graft made from artificial material is used to create a detour around a blocked artery.
- Tibioperoneal bypass is used for PVD affecting the arteries in the lower leg or foot.
- Femoropopliteal (fem-pop) bypass surgery is used for PVD affecting the arteries above and below the knee.
- Embolectomy is a technique in which an embolic clot on the wall of the artery is removed, using an inflatable balloon catheter.
- Thrombectomy is a technique in which a balloon catheter is inserted into the affected artery beyond a blood clot. The balloon is then inflated and pulled back, bringing the clot with it.
An aneurysm occurs when weakened blood vessels bulge like balloons as blood flows through them. Once they have grown to a certain size, there is a risk of rupture and life-threatening bleeding. There are two types of aortic aneurysms: abdominal aortic aneurysm (AAA) and thoracic aortic aneurysm. This classification is based on where the aneurysm occurs along the aorta. Aneurysms are more common in the abdominal section of the aorta than the thoracic section.
Most blood clots originate in the legs, but they can also form in the veins of arms, the right side of the heart, or even at the tip of a catheter placed in a vein. The following venous disease conditions usually occur in the veins of the legs:
- varicose veins
- venous stasis disease
- deep vein thrombosis (DVT)
- blood clots
Carotid artery disease is a condition in which the arteries in the neck that supply blood to the brain become clogged; this condition can cause a stroke.
Lymphatic obstruction involves blockage of the lymph vessels, which drain fluid from tissues throughout the body and allow immune cells to travel where they are needed. Some of the causes of lymphatic obstruction (also known as swelling of the lymph passages), include infections such as chronic cellulitis, or parasitic infections such as filariasis, trauma, tumors, certain surgeries including mastectomy, and radiation therapy. There are rare forms of congenital lymphedema that probably result from abnormalities in the development of the lymphatic vessels. Most patients with lymphedema will not need surgery, as the symptoms are usually managed by other techniques. Surgical therapy for lymphedema includes removal of tissue containing abnormal lymphatics, and less commonly, transplant of tissue from areas with normal lymphatic tissues to areas with abnormal lymphatic drainage. In rare cases, bypass of abnormal lymphatic tissue is attempted, sometimes using vein grafts.
Other examples of vascular surgery include:
- cerebral aneurysm
- acute arterial and graft occlusion
- carotid endarterectomy
- endovascular grafting
- vasculogenic erectile dysfunction
- renal artery aneurysm
- surgery on varicose veins
- lower extremity amputation
In order for a patient to be diagnosed with a vascular disease, they must be clinically evaluated by a vascular surgeon, which includes a history and physical examination . A vascular surgeon also treats vascular disorders by non-operative means, including drug therapy and risk factor management.
The symptoms produced by atherosclerosis, thrombosis, embolisms, or aneurysms depend on the particular artery affected. These conditions can sometimes cause pain, but often there are no symptoms at all.
A physician has many ways of feeling, hearing, measuring, and even seeing arterial blockages. Many arteries in the body can be felt or palpated. A doctor can feel for a pulse in an area he or she believes afflicted. Usually the more advanced the arteriosclerosis, the less pulse in a given area.
As the artery becomes blocked, it can cause a noise very much like water roaring over rocky rapids. Your physician can listen to this noise (bruit) directly, or can use special amplification systems to hear the noise.
There are other tests that can be done to determine if arterial blood flow is normal:
- ankle-brachial index (ABI) test
- segmental pressure test
- ultrasound scan
- magnetic resonance imaging
- computed tomography scan
- duplex ultrasound scanning
There may be no symptoms of vascular disease caused by blood clots until the clot grows large enough to block the flow of blood through the vein. The following symptoms may then come on suddenly:
- sudden swelling in the affected limb
- reddish blue discoloration
- enlargement of the superficial veins
- skin that is warm to the touch
The physician will probably do an evaluation of all organ systems including the heart, lungs, circulatory system, kidneys, and the gastrointestinal system. The decision whether to have surgery or not is based on the outcome of these evaluations.
For high-risk patients undergoing vascular surgery, research has shown that taking oral beta-blockers one to two weeks before surgery and continuing for at least two weeks after the operation can significantly reduce the chance of dying or having a heart attack. Scientists suspect that the drug improves oxygen balance in the wall of the heart and stabilizes plaques in the arteries.
The length of time in intensive care and hospitalization will vary with each surgery, as will the recovery time, depending on numerous factors. Because surgery for an AAA is more serious, the patient can expect to be in intensive care for 24 hours, and in the hospital for five to 10 days, providing the patient was healthy and had a smooth operative and postoperative course. If there are complications, the hospital stay will likely increase. It may take as long as six months to fully recover from surgery for an AAA.
Living a “heart-healthy lifestyle” is the best way of preventing and controlling vascular disease: do not smoke; eat nutritious foods low in fat; exercise; maintain a healthy weight; and control risk factors such as high blood pressure, high cholesterol, diabetes, hypertension, and other factors that contribute to vascular disease.
Medications that may be used to treat PVD include:
- aspirin and other antiplatelet medications to treat leg pain
- statins to lower cholesterol levels
- medications to control high blood pressure
- medications to control diabetes
- anticoagulants are rarely, but not generally, used to treat PVD unless the person is at an increased risk for forming blood clots
All surgeries carry some risks. There is a risk of infection whenever incisions are required. Operations in the chest or those that involve major blood vessels carry a higher risk of complications. Patients who smoke, have high blood pressure, chronic lung or kidney disease, or other illnesses are at greater risk of complications during and after surgery. Other risks of vascular surgery include:
- failed or blocked grafts
- heart attack or stroke
- leg swelling if a leg vein is used
- people over 65 years are at greater risk for brain impairment after major surgery
- the more damaged the circulatory system is before surgery, the higher susceptibility to mental decline after vascular surgery
The patient should discuss risks with their surgeon after careful review of the patient’s medical history and a physical examination.
The success rate for vascular surgery varies depending on a number of factors which may influence the decision on whether to have surgery or not, as well as the results.
The chance that an aneurysm will rupture generally increases with the size of the aneurysm; AAAs smaller than 1.6 in (4 cm) in diameter have up to a 2% risk of rupture while ones larger than 2 in (5 cm) in diameter have a 22% risk of rupture within two years.
Arterial bypass surgery and peripheral bypass surgery have very good success rates. Most of those who undergo AAA surgery recover well, except in the case of a rupture. Most patients who have a ruptured aortic aneurysm die. Surgery for an already ruptured aneurysm is not usually successful, due to excessive, rapid blood loss.
Surgical therapy for lymphedema has met with limited success, and requires significant experience and technical expertise.
Morbidity and mortality rates
Peripheral vascular disease affects 10 million people in the United States, including 5% of those over 50. Only a quarter of PVD sufferers are receiving treatment. More than five million people in the United States develop DVT each year. More than 600,000 Americans experience a pulmonary embolism every year. Of those, approximately 200,000 people die from the condition.
There a few alternatives to treating vascular disease, although extensive research has not been done. Acupuncture is used to aid in hypertension and chelation therapy is thought to stabilize the effects of vascular disease. The focus should be on maintaining a proper diet and being aware of a family history of vascular disease so as to catch it as early as possible.