Wolff-Parkinson-White (WPW) Syndrome ECG
Wolff-Parkinson-White Syndrome
An accessory pathway bypasses the AV node and results in an early onset of ventricular depolarization (i.e. preexcitation). The lack of AV nodal delay is reflected on the ECG by a short PR interval that is less than 120 milliseconds in duration. Early depolarization of the ventricles occurs outside of the conduction system (i.e., via slow muscle fibre to muscle fibre conduction), which results in a slurred upstroke of the QRS complex. The QRS complex in WPW is wide because it is a composite of ventricular activation via both the bypass tract and the AV node. The initial portion of the QRS complex (i.e., the delta wave) is the result of aberrant ventricular depolarization via the accessory pathway, while the terminal portion reflects normal ventricular depolarization via AV node. A deep s wave in lead V1 indicates right to left-sided conduction; ventricular depolarization begins in the right side of the heart and then spreads towards the left ventricle. The ECG correlates of WPW syndrome may not be present during sinus rhythm and can also vary from day to day. As well, the WPW pattern can mask the findings that can occur with myocardial ischemia/infarction and other pathologies.
📺 Subscribe To My Channel and Get More Great Quizzes and Tutorials
/ @med4vl
0:00 Intro
00:11 Short PR Interval
00:41 Delta Wave
01:03 Wide QRS Complex
01:27 Right-Sided Bypass Tract (Type B pattern)
01:45 Pitfalls
#FOAMed #cardiology #ECG
Disclaimer: All the information provided by Medical Education for Visual Learners and associated videos are strictly for informational purposes only. It is not intended as a substitute for medical advice from your health care provider or physician. It should not be used to overrule the advice of a qualified healthcare provider, nor to provide advice for emergency medical treatment. If you think that you or someone that you know may be suffering from a medical condition, then please consult your physician or seek immediate medical attention.