A 55-year-old man has been diagnosed with Stokes- Adams syndrome. Two minutes after the onset of syncopal attack, which of the following is the pacemaker of the hea?

During a Stokes-Adams syndrome attack, total A-V block suddenly begins. After a few seconds, some pa of the Purkinje system beyond the block, usually in the distal pa of the A-V node beyond the blocked point in the node, or in the A-V bundle, begins discharging rhythmically at a rate of 15 to 40 times per minute and acting as the pacemaker of the ventricles. This phenomenon is called ventricular escape.