This is a recording from an older man in the surgical intensive care unit. He was recovering from a motor vehicle accident where he sustained a chest injury from his seat belt. The rhythm is sinus rhythm with a prolonged p wave duration in lead III( >140ms) and a pronounced terminal negativity in V1 suggtestive of left atrial abnormality. The QRS is wide with a duration of 137ms and a superior and right ward axis. There is an Rsr' in V1 ahd the S wave is greater than the R in V6. This is an unusual pattern for aberrance and is more in keeping with ventricular ectopy. In this case thought this appears to be a right bundle branch block with a possible left posterior hemi-block. Of note, in spite of this conduction disturbance the patient was able to sustain reentrant supraventricular tachycaridas requiring intravenous adenosine for termination.