Wolff-Parkinson-White syndrome (WPW) is a condition of the heart where there's an abnormal electrical connection between the top (atrium) and the bottom (ventricles) of the heart. This extra connection or pathway could result in periods of high heart rate.
In normal conditions, the electrical signal from the sinus node (command center of the heart) passes through the AV node to get to the ventricles to create a heartbeat. However, in WPW, the signal can pass through the extra pathway as well as the AV node, causing the heart to beat unusually fast. This phenomenon is known as re-entry tachycardia and is one of the most common signs of WPW.
An electrocardiogram test (an ECG or EKG) may pick up this additional electrical pathway. Medical experts do not know the exact cause of WPW, but it is typically something you are born with. However, the tachycardias (fast heart rate) related to WPW may not occur until later in life.
How to Spot WPW on Your Watch ECG
The main feature of WPW is that during the normal sinus heartbeat, the time between the top of the heart beating (P-wave) and the bottom part of the heart beating (QRS complex), known as the PR interval, is shorter than normal (less than 120 milliseconds). There is also typically a "delta wave," which is an electrical signal at the beginning of the QRS complex that makes it wider than normal.
While a smartwatch single-lead ECG can indicate the presence of a potential WPW, it is important to visit a doctor as soon as possible for a clinical diagnosis which will include a full, 12-lead ECG. In addition, you may find it helpful to record any symptoms when you record your smartwatch ECG, such as palpitations and what you were doing. This information will help your heart doctor give you an accurate diagnosis.
What Are Common Symptoms of WPW?
Most people with Wolff-Parkinson-White syndrome do not experience episodes of re-entry tachycardia for a long time. However, the symptoms can appear at any age. Common symptoms include:
- Chest pain
The symptoms can last seconds, minutes, or hours, which vary between people's experiences. The symptoms may appear after exercising, after drinking caffeine or alcohol, or after an emotional episode but can also appear with no trigger. WPW leads to sudden death from a heart attack in less than 0.5% of cases.
Diagnosing WPW is usually done with an ECG. Your doctor may ask you to wear a 24 -or 48-hour monitor. Your smartwatch is helpful, as you can record when your heart beats faster and what you are doing. A cardiologist may wish to do further tests involving identifying an accessory pathway in the heart.
Treatment options include self-management techniques such as learning vagal measures to slow the heart and lifestyle changes. Sometimes people with WPW don't need any treatment, especially if they have no symptoms. However, others require medication or a procedure known as cardioversion to slow the heart rate. Another treatment is to electronically ablate the extra pathway in the heart, which cardiologists do as a standard procedure.
Arrhythmias That Can Look Like WPW
While WPW is fairly distinguishable from other arrhythmias, it’s possible to confuse it with supraventricular tachycardia (SVT). SVT is an erratic heartbeat and rhythm, making it difficult to interpret on an ECG. However, SVT usually doesn’t contain a delta wave, and the QRS complex is narrow instead of wide.
Still Not Sure How to Spot WPW on Your Watch ECG?
Using smartwatch apps to monitor your health can help prevent the development of conditions such as high blood pressure, heart disease, and diabetes. In addition, use the smartwatch to control your exercise levels, sleep patterns, and eating habits.
Finally, if you are concerned about the ECG tracings from your smartwatch, you can get them reviewed by experts for arrhythmias like WPW within minutes. It will give you peace of mind and help you get an assessment if needed. Reach out to us (iOS and Android) for a review or if you have any questions.