EKG Drill Answer
This is Wolff-Parkinson-White Syndrome. Look for rhythm that is regular unless atrial fibrillation present, with heart rate that is normal (60-100 bpm). Notice that the P wave is normal. The PR interval is can be short (<0.12 sec). The QRS is typically usually wide (> 0.12 sec). Look for short PR interval and/or delta wave
A delta wave (positive or negative) distorts the early part of the QRS complex.