Atrial rate is greater than the ventricular rate.
The ventricular rate is determined by the origin of the escape rhythm. Normal in size and shape. If block at or below the bundle of His- usually due to anterior MI or extensive conduction system disease. Depends on the stability of the escape rhythm and patient's response to slow rate. If symptomatic and QRS wide, oxygen, IV, transcutaneous pacing until a transvenous pacemaker can be inserted.