The more distal the site of the escape pacemaker, the slower its rate and the more abnormal the QRS complex. This tracing was recorded from a 54 year old male following an episode of syncope. The atrial rate is 90 (P-P intrval = 0.64sec), the ventricular rate is 30 (R-R interval = 2.00 sec) and there is complete AV block with AV dissociation. The QRS complex is 0.16 seconds in duration and shows right bundle branch block. This indicates that the escape pacemaker is located in the left ventricle. Syncope occurring in the setting of high grade or complete AV block is referred to as Stokes-Adams disease. The syncope occurs as the result of ventricular tachycardia or even more profound bradycardia. This scenrio is prevented by ventricular pacing