Health Encyclopedia

Aortic dissection

Definition

Aortic dissection is a potentially life-threatening condition in which there is bleeding into and along the wall of the aorta, the major artery leaving the heart.

Alternative Names

Aortic aneurysm - dissecting

Causes, incidence, and risk factors

Aortic dissection most often occurs because of a tear or damage to the inner wall of the artery. This usually occurs in the thoracic (chest) portion of the aorta, but may also occur in the abdominal portion.

The aorta has different branches through which blood flows. An aortic dissection is classified as type A or B depending on where it begins and ends. Type A begins in the first (ascending) part of the aorta and typically moves to another part of the chest. Type B begins in the last (descending) part of the aorta and moves down the abdomen.

When a tear occurs, it creates two channels: One in which blood continues to travel and another where blood remains still. As the aortic dissection grows bigger, the channel with non-traveling blood can get bigger and push on other branches of the aorta.

An aortic dissection may also involve abnormal widening or ballooning of the aorta (aneurysm).

The exact cause is unknown, but risks include atherosclerosis (hardening of the arteries) and high blood pressure. Traumatic injury is a major cause of aortic dissection, especially blunt trauma to the chest as can be caused by hitting the steering wheel of a car during an accident.

Other risk factors and conditions associated with the development of aortic dissection including:

Pregnancy
Marfan's syndrome
Pseudoxanthoma elasticum
Ehlers-Danlos syndrome
Coarctation (narrowing) of the aorta
Bicuspid aortic valve
Vascular inflammation due to conditions such as arteritis and syphilis
Connective tissue disorders
Heart surgery or procedures

Aortic dissection occurs in approximately 2 out of every 10,000 people. It can affect anyone, but is most often seen in men aged 40 to 70.

Symptoms

Chest pain
- Sudden, severe, sharp, stabbing, tearing, or ripping
- Located below the chest bone, then moves under the shoulder blades or to the back
- May move to shoulder, neck, arm, jaw, abdomen, or hips
- Location may change -- pain typically moves to the arms and legs as the aortic dissection gets worse
Changes in thought ability, confusion, disorientation
Decreased movement, any location
Decreased sensation, any location
Intense anxiety, anguish
Pallor
Rapid, weak pulse
Profuse sweating (clammy skin)
Dry skin
Dry mouth
Thirst
Nausea and vomiting
Dizziness
Fainting
Shortness of breath -- difficulty breathing when lying flat (orthopnea)

The symptoms usually begin suddenly.

Signs and tests

The health care provider will listen to your heart, lungs, and abdomen with a stethoscope. A "blowing" murmur over the aorta, a heart murmur, or other abnormal sound may be heard.

There may be a difference in blood pressure between the right and left arms, or between the arms and the legs.

There may be low blood pressure, bulging neck veins, or signs resembling a heart attack. There may be signs of shock (inadequate blood flow to the body tissues), but with normal blood pressure.

Aortic dissection or aortic aneurysm may be revealed on:

Echocardiogram
Transesophageal echocardiogram (TEE)
Chest x-ray -- may show chest widening or fluid in the lining of the lung (pleural effusion)
Chest MRI
CT scan of chest with dye
Aortic angiography
Doppler ultrasonography (occasionally performed)

Treatment

The goal of treatment is prevention of complications. Hospitalization is required.

Type A aortic dissections require surgery to repair the aorta. Type B aortic dissections may be treated with medication.

Anti-hypertensives (drugs that lower blood pressure) may be prescribed. These drugs may be given through a vein (intravenously). Strong pain relievers are usually needed. Heart medications such as beta-blockers may reduce some of the symptoms.

Surgery to repair or replace the damaged section of aorta can cure the condition in some cases. If the aortic valve is damaged, valve replacement is necessary. If the coronary (heart) arteries are involved, a coronary bypass is also performed.

Expectations (prognosis)

Aortic dissection is life threatening. The chance of death within the first 48 hours is 1% per hour for patients who do not get treatment. The condition can be cured with surgery if it is done before the aorta ruptures. Less than half of patients with ruptured aorta survive.

Complications

Bleeding from the aorta
Aortic rupture causing rapid blood loss, shock
Clot formation
Insufficient circulation past the area of the dissection
Irreversible kidney failure
Stroke
Heart attack
Cardiac tamponade

Calling your health care provider

If you have symptoms of aortic dissection or severe chest pain, call 911 or your local emergency number, or go to the emergency room as quickly as possible.

Prevention

Adequate treatment and control of atherosclerosis (hardening of the arteries) and high blood pressure may reduce the risk. Take safety precautions to prevent injuries. Many cases are not preventable.

Review Date:5/27/2006
Reviewed By:Alan Berger, MD, Assistant Professor, Divisions of Cardiology and Epidemiology, University of Minnesota, Minneapolis, MN. Review provided byVeriMed Healthcare Network.

ADAM Quality A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.

Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.