Definition

Wolff-Parkinson-White syndrome (WPW) is a problem with the heart’s electrical activity. It causes the heart to beat with an irregular rhythm and faster than normal. This is called tachyarrhythmia. If left untreated, it can increase the risk of sudden death.

Causes

WPW happens when the heart's signals travel along an extra, abnormal pathway. The signals make the lower chamber of the heart contract abnormally. As a result, the heart beats much faster than it should.

The extra pathway is caused by abnormal tissue that connects the heart’s chambers. The tissue forms before birth.

It is not clear what causes this to happen. Rarely, it may be due to a gene that is inherited.

Electrical Conduction System of the Heart Copyright © Nucleus Medical Media, Inc.

Risk Factors

Rarely, WPW syndrome is found in families. Otherwise, there are no known risk factors.

Symptoms

Some people with WPW syndrome have no symptoms. In those that do, symptoms may be:

• Fast heartbeats that start and stop suddenly
• Pounding heartbeats
• Chest pain or tightness
• Lightheadedness
• Fainting
• Problems breathing

Rarely, a person will go into cardiac arrest and lose consciousness.

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done.

Tests will be done to diagnose the condition. They may include:

• Electrocardiogram (ECG)—tests electrical activity of the heart
• Holter monitoring—a device worn to measure heart activity over 24 to 48 hours
• Electrophysiology study—wires are passed into the heart to measure activity and find the extra pathway

Treatment

People without symptoms may not need treatment. For those who do have symptoms, the goal is to slow the fast heartbeats. It is also to ease or stop other symptoms.

Options may be:

• Medicine to regulate the heart signals
• Radiofrequency ablation—a procedure where heat is used to destroy the abnormal pathway
• Open heart surgery—(rarely done) to destroy the abnormal pathway

Rarely, cardiac arrest happens. In this case, defibrillation gives the heart a brief shock. This changes the fast, abnormal heartbeats to normal heartbeats.

Prevention

There are no known guidelines to prevent WPW syndrome.