Vascular Surgery

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Vascular Surgery

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Morbidity and mortality rates
Alternatives

Definition

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).

Purpose

Vascular surgery is indicated when a patient has vascular disease that cannot be treated by less invasive, non-surgical 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.

Demographics

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. A large percentage of the 10 million people in the United States who may have peripheral vascular disease (PVD) 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
  • pregnancy
  • prolonged periods of inactivity sitting, standing, or bed rest
  • smoking
  • obesity
  • hypertension, diabetes, high cholesterol, or other conditions that affect the health of the cardiovascular system
  • lack of exercise

Description

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 vesels 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.

KEY TERMS

Ankle-brachial index (ABI) test— A means of checking the blood pressure in the arms and ankles using a regular blood pressure cuff and a special ultrasound stethoscope (Doppler). The pressure in the ankle is compared to the pressure in the arm.

Aorta— A large, elastic artery beginning at the upper part of the left ventricle of the heart that becomes the main trunk of the arterial system.

Aortic aneurysms— Occurs when an area in the aorta (the main artery of the heart) is weakened and bulges like a balloon.

Arteriogram— A test to check the blood pressure at several points in the leg by using a blood pressure cuff and a Doppler. The patient is then asked to walk on a treadmill, after which the ankle pressure is taken again to determine if the pressure decreased after walking.

Abdominal aortic aneurysm— Occurs when an area in the aorta (the main artery of the heart) is weakened and bulges like a balloon. The abdominal section of the aorta supplies blood to the lower body.

Aneurysm— A weakening of the artery wall, due to atherosclerosis, causing a bulge that can rupture, and lead to thrombosis or embolism.

Angiography or angiogram— An x-ray exam of the arteries and veins (blood vessels) to diagnose blockages and other blood vessel problems.

Atherosclerosis— A form of arteriosclerosis affecting the innermost area of the artery; a series of calcified deposits that can close down the vessel.

Arteriogram— An x-ray picture of an artery achieved by injecting an opaque dye with a needle or tube into the affected artery.

Artery— A blood vessel conveying blood in a direction away from the heart.

Bruit— A roaring sound created by a partially blocked artery.

Capillary— Smallest extremity of the arterial vessel, where oxygen and nutrients are released from the blood into the cells, and cellular waste is collected.

Carotid artery— Major artery leading to the brain, blockages of which can cause temporary or permanent strokes.

Carotid artery disease— A condition in which the arteries in the neck that supply blood to the brain become clogged, causing the danger of a stroke.

Carotid endarterectomy— A surgical technique for removing intra-arterial obstructions of the internal carotid artery.

Cerebral aneurysm The dilation, bulging, or ballooning out of part of the wall of a vein or artery in the brain.

Cholesterol— An abundant fatty substance in animal tissues. High levels in the diet are a factor in the cause of atherosclerosis.

Claudication— Attacks of lameness or pain chiefly in the calf muscles, brought on by walking because of a lack of oxygen reaching the muscle.

Computed tomography (CT) scan— A special type of x ray that can produce detailed pictures of structures inside the body.

Collaterals— Alternate pathways for arterial blood.

Coronary— Of or relating to the heart.

Embolism— Obstruction or closure of a vessel by a transported clot of foreign matter.

Endovascular grafting— A procedure that involves the insertion of a delivery catheter through a groin artery into the abdominal aorta under fluoroscopic guidance.

Intracranial— Existing or occurring within the cranium; affecting or involving intracranial structures.

Lower extremity amputation— To cut a limb from the body.

Lymphangiography— Injection of dye into lymphatic vessels followed by x rays of the area. It is a difficult procedure, as it requires surgical isolation of the lymph vessels to be injected.

Lymphoscintigraphy— A technique in which a radioactive substance that concentrates in the lymphatic vessels is injected into the affected tissue and mapped using a gamma camera, which images the location of the radioactive tracer.

Magnetic resonance imaging (MRI)— A noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within the body induced by the application of radio waves.

Plethysmography— A test in which a patient sits inside a booth called a plethysmograph and breathes through a mouthpiece, while pressure and air flow measurements are collected to measure the total lung volume.

Pulmonary embolism— A blocked artery in the lung.

Renal artery aneurysm— An aneurysm relating to, involving, or located in the region of the kidneys.

Thoracic aortic aneurysm— Occurs when an area in the thoracic section of the aorta (the chest) is weakened and bulges like a balloon. The thoracic section supplies blood to the upper body.

Thrombus— A blood clot that may form in a blood vessel or in one of the cavities of the heart.

Thrombosis— The formation or presence of a blood clot within a blood vessel.

Thrombolysis— A treatment that opens up blood flow and may prevent permanent damage to the blood vessels.

Ulcer— A lesion or rough spot formed on the surface of an artery.

Vascular— Relating to the blood vessels.

Ultrasound scan— The scan produces images of arteries on a screen and is used to evaluate the blood flow, locate blockages, and measure the size of the artery.

Vasculogenic erectile dysfunction— The inability to attain or sustain an erection satisfactory for coitus, due to atherosclerotic disease of penile arteries, inadequate impedance of venous outflow (venous leaks), or a combination of both.

Venous stasis disease— A condition in which there is pooling of blood in the lower leg veins that may cause swelling and tissue damage, and lead to painful sores or ulcers.

Varicose veins — Twisted, enlarged veins near the surface of the skin, which develop most commonly in the legs and ankles.

A few common diseases affecting the arteries are peripheral vascular disease (PVD), carotid artery disease, and aortic aneurysms.

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 surgery techniques used for severe PVD include:

  • 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. Venous disease conditions that usually occur in the veins of the legs include:

  • varicose veins
  • phlebitis
  • venous stasis disease
  • deep vein thrombosis (DVT)
  • claudication
  • 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

Diagnosis/Preparation

In order for a patient to be diagnosed with a vascular disease, he or she 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. The 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, including:

  • ankle-brachial index (ABI) test
  • arteriogram
  • segmental pressure test
  • ultrasound scan
  • magnetic resonance imaging (MRI)
  • computed tomography (CT) scan
  • angiography
  • lymphangiography
  • lymphoscintigraphy
  • plethysmography
  • 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. Symptoms that may come on suddenly include:

  • pain
  • 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.

Aftercare

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. The hospital stay will likely increase if there are complications. 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: quit smoking; 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 legpain
  • statins to lower cholesterol levels
  • medications to control high blood pressure
  • medications to control diabetes
  • anticoagulants (these are rarely, but not generally, used to treat PVD unless the person is at an increased risk for forming blood clots)

Risks

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 that have

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PREFORMED?

A vascular surgeon performs the procedure in a hospital operating room. Applicants for residency training in vascular surgery must have successfully completed a general surgery residency and be eligible for the board examination in general surgery. An individual must meet the standards set by the Vascular Surgery Board of the American Board of Surgery for cognitive knowledge and hypothetical case management. At the completion of a vascular surgery residency, both a written and oral examination must be completed before certification. A vascular surgeon is required to undergo periodic written reexamination.

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:

  • bleeding
  • failed or blocked grafts
  • heart attack or stroke
  • smoking
  • 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
  • impotence

The patient should discuss risks with the surgeon after careful review of the patient’s medical history and a physical examination.

Normal results

The success rate for vascular surgery varies depending on a number of factors that 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

QUESTIONS TO ASK THE DOCTOR

  • Can my vascular disease be controlled with lifestyle changes?
  • If a procedure is required, am I a candidate for a less invasive, interventional radiology treatment?
  • What are the risks and benefits of this operation?
  • What are the normal results of this operation?
  • What happens if this operation does not go as planned?
  • What is the expected recovery time?

undergo AAA surgery recover well, except in the case of a rupture. Most patients who have a ruptured aortic aneurysm die 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 two million people in the United States develop DVT each year. More than 650,000 Americans experience a pulmonary embolism every year. Of those, approximately 200,000 people die from the condition.

Alternatives

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.

Resources

BOOKS

Khatri, V. P., and J. A. Asensio. Operative Surgery Manual, 1st ed. Philadelphia: Saunders, 2003.

Libby, P., et al. Braunwald’s Heart Disease, 8th ed. Philadelphia: Saunders, 2007.

Mason, R. J., et al. Murray & Nadel’s Textbook of Respiratory Medicine, 4th ed. Philadelphia: Saunders, 2007.

Townsend, C. M., et al. Sabiston Textbook of Surgery, 17th ed. Philadelphia: Saunders, 2004.

PERIODICALS

Abir, Farshad, Iannis Kakisis, and Bauer Sumpio. “Do Vascular Surgery Patients Need a Cardiology Work-up? A Review of Preoperative Cardiac Clearance Guidelines in Vascular Surgery.” European Journal of Vascular and Endovascular Surgery 25, no. 2 (2003): 110–117.

Moore, Wesley S., M.D., G. Patrick Clagett, M.D., Frank J. Veith, M.D., Gregory L. Moneta, M.D., Marshall W. Webster, M.D. et al. “Guidelines for Hospital Privileges in Vascular Surgery: An Update by an Ad Hoc Committee of the American Association for Vascular Surgery and the Society for Vascular Surgery.” Journal of Vascular Surgery 36, no. 6 (2002): 1276–1282.

ORGANIZATIONS

American Board of Vascular Surgery (ABVS). 900 Cummings Center, #221-U, Beverly, MA 01915. http://abvs.org (accessed April 16, 2008).

The National Heart, Lung and Blood Institute. 6701 Rockledge Drive, P.O. Box 30105, Bethesda, MD 20824-0105. (301) 592-8573. E-mail: [email protected]. http://www.nhlhi.nih.gov (accessed April 16, 2008).

National Institutes of Health (NIH), Department of Health and Human Services. 9000 Rockville Pike, Bethesda, MD 20892.

The Society for Vascular Surgery. 900 Cummings Center, #221-U, Beverly, MA 01915. http://www.vascularweb.org (accessed April 16, 2008).

Society of Interventional Radiology. 10201 Lee Highway, Suite 500. Fairfax, VA. 22030. (800) 488-7284. E-mail: [email protected]. http://www.sirweb.org/index.shtml (accessed April 16, 2008).

The U.S. Department of Health and Human Services. 200 Independence Avenue, S.W., Washington, DC 20201. (877) 696-6775.

Valley Baptist Heart and Vascular Institute. 2101 Pease Street, P.O. Drawer 2588, Harlingen, TX 78550. (956) 389-4848.

Crystal H. Kaczkowski, MSc

Rosalyn Carson-DeWitt, MD

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