Description of the Disease
WPW syndrome is a type of supraventricular (above the ventricles) tachycardia. It is a symptom complex characterized by specific changes on the ECG and the occurrence of sudden episodes of rapid heart rate with high or very high heart rates (up to 250 beats per minute).
Causes of the Disease
The cause of WPW syndrome is the presence of a congenital additional electrical conduction pathway between the atria and ventricles. Normally, electrical impulses that set the heart rhythm are conducted through a specialized conduction system of the heart from the atria to the ventricles through the atrioventricular node (AV node), allowing the atria to complete contraction before ventricular contraction begins.
With the presence of a second (additional) conduction pathway, the electrical impulse under certain conditions can "return back" to the atria through that pathway and then pass again, through the normal AV node, down to the ventricles, and so on. This creates a "loop," where the impulse travels and causes the heart to beat at a high rate. This mechanism is called re-entry and plays a significant role in the development of many heart rhythm disorders.
Symptoms of the Disease
Patients with WPW syndrome may experience sudden episodes of rapid heart rate, lasting from several minutes to several hours (less commonly), which also end suddenly. These episodes may be accompanied by dizziness, shortness of breath, pre-syncope, and chest pain.
If you experience heart rhythm disturbances or have these symptoms, seek immediate help from our specialists.
Diagnostics of the Disease
The diagnosis of WPW syndrome involves analyzing ECG data (or 24-hour ECG monitoring), which may reveal specific pre-excitation waves ("delta" waves) preceding the QRS complex.
Specific changes on the ECG are not always detected. In "concealed" WPW syndrome, they are absent. Conversely, if changes are present on the ECG, there may be no episodes of rapid heart rate.
If you experience the above-mentioned complaints, seek immediate medical attention from a cardiologist. The precise diagnosis is established through endocardial electrophysiological study (endocardial EPS). This procedure is performed without anesthesia, using local anesthesia in a X-ray operating room. After anesthesia, catheters are introduced into the heart through a vein puncture, located in the thigh, for intracardiac ECG recording. Using stimulation techniques, the mechanism of the existing arrhythmia is identified, thus establishing an accurate diagnosis.
If endocardial EPS confirms the presence and establishes the mechanism of the arrhythmia, catheter ablation (radiofrequency ablation, RFA) is almost always performed simultaneously.
Treatment of the Disease
Drug therapy for WPW syndrome is often ineffective. The only radical and effective treatment is radiofrequency ablation (RFA) of the additional conduction pathway.
Learn more about radiofrequency ablationPrognosis of the Disease
Patients with WPW syndrome and recurrent tachycardia episodes are candidates for catheter ablation of the additional conduction pathway.
In 50% of patients with WPW syndrome, including young individuals, atrial fibrillation occurs. The development of atrial fibrillation episodes conducted through the additional pathway in patients with WPW syndrome is a potentially life-threatening condition, as there is a risk of arrhythmia transformation into ventricular fibrillation.