What Is Wolff-Parkinson-White (WPW) Syndrome?
Wolff-Parkinson-White (WPW) syndrome is a birth defect in which the heart develops an extra, or “aberrant,” electrical pathway. This can lead to a rapid heart rate, which is called tachycardia. Medications may help alleviate the symptoms. However, a surgical procedure called catheter ablation is usually used to destroy the extra pathway and restore normal heart rhythm.
The first sign of WPW syndrome is usually a rapid heart rate.
The symptoms of WPW syndrome may occur in infants or adults. In infants, the symptoms may include:
- severe fatigue or lethargy
- a loss of appetite
- shortness of breath
- rapid, visible pulsations of the chest
In children, teenagers, and adults, the symptoms may include:
- heart palpitations
- a racing heart
- shortness of breath or difficulty breathing
- sudden death (rarely)
In some people, the symptoms will not appear at all or will appear only periodically in short episodes.
Doctors aren’t sure what causes WPW syndrome. The extra electrical pathway in the heart is present at birth, so it’s likely caused by some abnormality that occurs during fetal development. A small percentage of people with WPW syndrome have been found to have a gene mutation that is thought to be responsible for the disorder.
In a normal heart, the heartbeat is initiated by the sinus node in the upper right section of the heart muscle. This is where the electrical impulses that start each heartbeat begin. Those impulses then travel to the atria, or upper heart chambers, where the initiation of contraction occurs. Another node called the atrioventricular node, or AV node, then sends the impulse to the lower heart chambers called the ventricles where ventricular contraction occurs and the blood is pumped out of your heart. Ventricular contraction is much stronger than atrial contraction. The coordination of these events is essential for maintaining a normal, regular heartbeat and rhythm.
In a heart affected by WPW syndrome, however, an extra electrical pathway can interfere with the normal heartbeat. This extra pathway creates a shortcut for the electrical impulses. As a result, these impulses may activate the heartbeats too early or at the wrong time.
If it’s left untreated, the abnormal heartbeat, arrhythmia, or tachycardia, can cause blood pressure, heart failure, and even death.
Babies born to parents with WPW syndrome may be more at risk of developing the condition. Babies with other congenital heart defects may also be at a higher risk.
People experiencing a fluttering or racing heartbeat usually tell their doctors. The same applies to those experiencing chest pain of difficulty breathing. However, if you don’t have symptoms, the condition may go unnoticed for years.
If you have a racing heartbeat, your doctor will likely perform a physical exam and conduct tests that measure your heart rate over time to check for tachycardia and diagnose WPW syndrome. These heart tests may include:
An electrocardiogram (EKG) uses small electrodes attached to your chest and arms to record the electrical signals traveling through your heart. Your doctor can check these signals for any signs of an abnormal electrical pathway. You can also do this test at home with a portable device. Your doctor will likely give you either an EKG device called a Holter monitor or an event recorder that can be worn as you perform your daily activities. These monitors can record your heart’s rhythm and rate throughout the day.
During this test, the doctor threads a thin, flexible catheter with electrodes on its tip through your blood vessels and into various parts of your heart, where they can map its electrical impulses.
If you’re diagnosed with WPW syndrome, you have several treatment options, depending on your symptoms. If you’re diagnosed with WPW syndrome but don’t have any symptoms, your doctor may recommend that you wait and continue follow-up appointments. If you’re having symptoms, the treatment may include the following:
The most common method of treatment, this procedure destroys the extra electrical pathway in your heart. Your doctor inserts a tiny catheter into an artery in your groin and threads it up into your heart. When the tip reaches your heart, the electrodes are heated. This procedure will then destroy the area that’s causing the abnormal heartbeat with radiofrequency energy.
Anti-arrhythmic drugs are available to treat abnormal heart rhythms. These include adenosine and amiodarone.
If medications don’t work, your doctor may suggest cardioversion, which involves applying an electrical shock to the heart. This can restore normal rhythm. Your doctor will give you anesthesia to put you to sleep and then place paddles or patches on your chest to deliver the shock. This procedure is usually reserved for people whose symptoms aren’t relieved by other treatments.
Open-heart surgery may also be used to treat WPW syndrome but usually only if you need surgery to treat another heart condition.
If you continue to have problems with your heart rhythm after treatment, your doctor may implant an artificial pacemaker to regulate your heart rhythm.
For those with mild cases of WPW syndrome, lifestyle adjustments can help limit abnormal heart rhythms. Avoiding the following can help you maintain a normal heartbeat:
- pseudoephedrine, which is a nasal decongestant
Your doctor may also recommend what are called “vagal maneuvers,” which can help slow a fast heart rate. These include coughing, bearing down as though you’re having a bowel movement, and placing an ice pack on your face.
If you use medications to treat WPW syndrome, you may experience unwanted side effects and you may not want to continue taking such medications in the long term. In those cases, other treatments such as catheter ablation may be recommended.
Catheter ablation is successful at curing WPW syndrome in about 80 to 95 percent of cases. Success depends on how many alternative electrical pathways you have and where they are in your heart.
If your condition isn’t cured by catheter ablation, you still have other treatment options, such as cardioversion or open-heart surgery. Everyone who has the disorder will require follow-up monitoring to ensure that their hearts are functioning normally.