Definition Wolff–Parkinson–White syndrome (WPW) is a ventricular pre-excitation syndrome associated with abnormal conduction pathways between the atria and ventricle. Classic findings on the ECG are the delta wave (slurred upstroke of QRS) and shortened PR interval (<120s). Tachycardias may be narrow complex (associated with anterograde conduction through accessory pathway) or wide complex (associated with retrograde […]