To diagnose Wolff-Parkinson White (WPW) syndrome, the physician will begin by taking a complete medical history. This will include the patient’s family history, particularly for cardiovascular conditions and current symptoms. The physician will then give the patient a complete physical examination, during which blood pressure will be measured and the heart will be heard through a stethoscope. If a patient with Wolff-Parkinson-White (WPW) syndrome is having abnormal heart rhythms (arrhythmias), he or she will have normal or low blood pressure and a heart rate of approximately 150 to 250 beats per minute (about 90 to 150 beats faster than normal).

For individuals with suspected WPW, the physician is likely to order a painless test called an electrocardiogram (EKG). The EKG of someone with WPW syndrome will show a delta wave that signals the presence of an extra electrical pathway. This wave is visible even if the patient is in a normal heart rhythm. If signs of WPW are not immediately seen on an EKG, the patient may need to wear a small, continuous EKG Holter monitor for 24 hours to assess for the condition.

An electrophysiology study (EPS) is a minimally invasive test that may follow the EKG. The EPS is a procedure in which a thin tube (catheter) is inserted into a vein or artery (e.g., in the groin) and guided to the heart. Once in place, it can be used to perform specific, essential measurements of the heart’s electrical activity and pathways. The catheter can locate the extra electrical pathway and determine the extent to which electrical impulses are traveling through it. In some instances, the physician will also perform a catheter ablation, which is a catheter-based procedure that eliminates (ablates) the abnormal pathway.