Brief overview
- Treatment: Cauterization of the additional conduction pathways (ablation), medication, electrocardioversion
- Symptoms: Does not occur in every patient, sudden rapid heartbeat or palpitations, heart stumbling, sometimes dizziness, chest pain, shortness of breath
- Causes: As yet unknown, possibly embryonic maldevelopment of the heart, often in combination with other congenital heart defects
- Diagnosis: Medical history, physical examination, ECG, long-term ECG, event recorder, exercise ECG, electrophysiological examination (EPU)
- Disease progression and prognosis: Life expectancy generally normal, risk of cardiac arrhythmia with frequent palpitations
What is WPW syndrome?
WPW syndrome is a cardiac arrhythmia. The name Wolff-Parkinson-White syndrome goes back to the American cardiologists L. Wolff, P.D. White and J. Parkinson. In 1930, they described the signs of WPW syndrome in young patients. These include attacks of sudden palpitations (tachycardia), which occur regardless of physical exertion or stress, and changes in the electrocardiogram (ECG).
Additional conduction pathway
In WPW syndrome, those affected have an additional (accessory) conduction pathway between the atrium and ventricle, the so-called Kent bundle. The impulses arriving from the sinus node are therefore transmitted to the ventricles via both the AV node and the Kent bundle. As the impulse arrives faster at the ventricles via the Kent bundle, premature excitation occurs here.
As the additional pathway also conducts in the “wrong” direction, the electrical signals from the muscle cells in the ventricles return to the atrium. This results in a so-called circular excitation between the atria and ventricles. This causes the heart to beat very quickly, but at a steady rhythm.
The additional conduction pathway of WPW syndrome is congenital. Symptoms such as palpitations usually occur in adolescence, sometimes as early as infancy or as late as adulthood. WPW syndrome is more common in men than in women.
WPW syndrome: therapy
The only, but very effective way to cure those affected by WPW syndrome is ablation. This is an intervention in which the additional pathway is obliterated. Medication only temporarily alleviates the symptoms of WPW syndrome.
EPU and ablation
The so-called electrophysiological examination (EPU) is of the greatest importance in the treatment of WPW syndrome. During the EPU, it is possible to locate the additional conduction pathway and directly obliterate it (catheter ablation).
This allows the faulty conduction in the heart to be permanently interrupted. Ablation cures WPW syndrome in almost 99 percent of cases. For safety reasons, people in certain occupational groups, such as pilots or train drivers, who have been diagnosed with WPW syndrome are only allowed to continue working if they have undergone successful ablation.
Medication
Certain medications, such as adenosine or ajmaline, stop the palpitations caused by WPW syndrome. Those affected usually receive these via a vein. There are also medications that sufferers take permanently to prevent palpitations. Beta-blockers are an example of this.
Electrocardioversion
Electrocardioversion is sometimes necessary in cases of tachycardia. This involves the patient’s heart receiving a brief electric shock via two electrodes on the chest. The patient is usually anaesthetized for this. The electric shock sometimes causes the heart to return to its normal rhythm.
WPW syndrome: symptoms
One of the most common symptoms is a sudden rapid heartbeat (tachycardia). The heart beats between 150 and 240 times per minute. At rest, 60 to 80 beats per minute are normal. The pulse is very regular in WPW tachycardia.
Some sufferers experience the palpitations as an increased pounding of the heart. In medicine, this is referred to as palpitations. Other sufferers experience heart palpitations. These sensations usually disappear just as abruptly as they came. In addition, some sufferers experience dizziness, chest pain and shortness of breath.
Fear and fainting
The palpitations trigger anxiety in many sufferers. Dizziness and shortness of breath intensify this feeling. Due to the high heart rate, the heart sometimes no longer pumps enough blood to the body organs. Some people therefore lose consciousness.
Symptoms in newborns
Very rarely, symptoms of WPW syndrome occur in babies. During a tachycardia, babies are noticeably pale and breathe very quickly. They may refuse to eat or drink, be easily irritable or cry a lot. In some cases, they may develop a fever.
WPW syndrome: causes and risk factors
WPW syndrome is also often found in the rare Ebstein anomaly, in which the heart valve between the right atrium and the right ventricle is malformed. As certain genetic changes are associated with WPW syndrome, the predisposition to WPW syndrome is very likely to be hereditary.
WPW syndrome: examinations and diagnosis
The doctor will first ask a few questions about the symptoms. For example, he will ask whether and how often attacks of palpitations occur, how long they last and whether they have led to dizziness or even fainting. This is followed by a physical examination.
Electrocardiogram
An important examination if WPW syndrome is suspected is the electrocardiogram (ECG). A recorder records the electrical activity of the heart. In some cases, the doctor will already diagnose WPW syndrome here.
Long-term ECG and event recorder
Sometimes a long-term ECG is necessary because the palpitations only occur in phases. A portable ECG device then records the heartbeat for 24 hours. Sometimes this enables the doctor to detect a tachycardia.
Exercise ECG
Occasionally, the doctor will carry out an exercise ECG. This involves the patient exercising on an exercise bike while connected to an ECG recorder. In some cases, the physical exertion triggers a tachycardia.
Electrophysiological examination
Sometimes an electrophysiological examination (EPE) is also carried out to diagnose WPW syndrome. This is a special form of cardiac catheterization. The doctor inserts two thin wires (catheters) into the great vena cava via the inguinal veins and pushes them up to the heart. There, the catheters measure electrical signals at various points on the heart muscle wall. During the examination, it is possible to treat the syndrome at the same time.
WPW syndrome: course of the disease and prognosis
WPW syndrome very rarely becomes dangerous. Those affected usually have a normal life expectancy. However, the palpitations are often very unpleasant and some people suffer greatly from the cardiac arrhythmia. As it sometimes lasts for hours, those affected are exhausted after a tachycardia. However, ablation is a very effective therapy that cures those affected in most cases.
Men between the ages of 30 and 50 are particularly at risk of developing this type of cardiac arrhythmia.
As WPW syndrome most likely has a hereditary component, it is advisable to inform family members about the disease if you develop it. If the doctor diagnoses WPW syndrome at an early stage, complications can be avoided.
WPW syndrome is often more dangerous for children than for adults due to the immature structure of the heart.
