Cardioembolic stroke

Definition

Stroke secondary to cardiogenic embolism is a loss of brain function caused by blood clots that develop in the heart and travel to the brain.

See also: Stroke

Alternative Names

Causes

A stroke is an interruption of the blood supply to any part of the brain. Strokes secondary to cardiogenic embolism are caused by moving blood clots (emboli) that develop in the heart. These clots travel through the bloodstream and become stuck in small arteries in the brain.

This type of stroke typically occurs suddenly, with immediate and severe loss of brain functions. It is not associated with type of activity, and can occur at any time.

Heart arrhythmias (such as atrial fibrillation) are commonly seen with this disorder, and are often the cause of the embolus. A heart muscle that is not beating strongly or regularly may result in blood remaining in the heart area, causing a clot to form. The clot can break off and travel to the brain.

Risks for stroke secondary to cardiogenic embolism include:

• History of heart valve replacement
• Arrhythmias (especially atrial fibrillation)
• Infective endocarditis
• Heart attack
• Mitral valve prolapse
• Other heart valve disorders
• Ischemic cardiomyopathy
• Blood clots anywhere in the body

Symptoms

Symptoms of stroke occur suddenly and include:

• Numbness or weakness of the face, arm, or leg (especially on one side of the body)
• Tingling or other abnormal sensations
• Confusion, trouble speaking, or understanding speech
• Problems seeing out of one or both eyes
• Dizziness
• Loss of coordination and balance, which can cause trouble walking
• Severe headache

Other symptoms may include:

• Vertigo (abnormal sensation of movement)
• Swallowing difficulties
• Personality changes
• Mood and emotion changes
• Urinary incontinence (lack of control over bladder)
• Lack of control over the bowels
• Sleepiness,stuporous, lethary
• Loss of consciousness
• Coma

Exams and Tests

A physical exam may reveal the following:

• Changes in vision or visual fields
• Clots in the retina of the eye
• Changes in reflexes including abnormal reflexes or abnormal extent of "normal" reflexes
• Abnormal eye movements
• Muscle weakness
• Decreased sensation

The pulse may be irregular. Abnormal sounds may be heard when listening to the heart with a stethoscope. There may be signs of splinter hemorrhages.

Tests include:

• Head CT scan
• MRI of head, MRA of the head
• ECG showing arrhythmia, such as atrial fibrillation
• Echocardiogram
• Transcranial Doppler (ultrasound of the head)

Treatment

Stroke is a serious condition. In all cases, the sooner treatment is given, the better the person will do, and the lower the chance of permanent disability or death.

Treatment depends on the severity of symptoms. Nearly all strokes, including this type, require hospitalization. Most patients will be admitted to an intensive care unit for close monitoring.

Clot-busting drugs (thrombolytic therapy) may be used. The drugs are used to restore normal blood flow. It is very important that such medication be given within 3 hours of the start of symptoms, so it's critical that the patient gets to the hospital very quickly. Other procedures can also be done to help break up the clot. This is another reason why it is important to seek medical care as quickly as possible.

If treatment with thrombolytic therapy is successful, the symptoms may completely go away.

However, there are strict rules regarding who should and should not receive thrombolytic therapy. The drugs have some risks of significant side effects. If the stroke was caused by bleeding in the brain, and not a clot, this therapy can be harmful.

There is no known cure for stroke if someone can not receive thrombolytic therapy. Physical therapy may be needed, depending on the affects of the stroke. Treatment is also aimed at prevention of future strokes.

The underlying heart disorder should be treated, which may include medications to control the heartbeat.

Outlook (Prognosis)

Stroke is the leading cause of disability among adults in the United States. It is the country's third leading cause of death.

How well a person does depends on the severity of the stroke and how quickly treatment is received.

Possible Complications

• Problems due to loss of mobility (joint contractures, pressure sores)
• Permanent loss of movement or sensation of a part of the body
• Bone fractures
• Muscle spasticity
• Permanent loss of brain functions
• Reduced communication or social interaction
• Reduced ability to function or care for self
• Early death
• Side effects of medications
• Breathing in food or fluids into the lungs (aspiration)
• Malnutrition

When to Contact a Medical Professional

Stroke is a medical emergency. Immediately go to the emergency room or call the local emergency number (911 in the United States) if signs of a stroke occur.

Prevention

Atrial fibrillation or other arrhythmias should be treated to prevent clot formation. TIA (transient ischemic attack) should be treated.

Aspirin therapy (81mg a day or 100mg every other day) is now recommended for stroke prevention in women under 65 as long as the benefits outweigh the risks. It should be considered for women over age 65 only if their blood pressure is controlled and the benefit is greater than the risk of gastrointestinal bleeding and brain hemorrhage

Mosca L, Banka CL, Benjamin EJ, et al. Evidence-Based Guidelines for Cardiovascular Disease Prevention in Women: 2007 Update. Circulation. 2007; Published online before print February 19, 2007.

Thom T, Haase N, Rosamond W, et al. Heart disease and stroke statistics--2006 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2006 Feb 14;113(6):e85-151. Epub 2006 Jan 11.

Ferro JM. Cardioembolic stroke: an update. Lancet Neurol. 2003 Mar;2(3):177-88.