they also may spend time in the o.r. as well if non-surgical pacing does not work...in these cases the cv surgeon will place the leads and defibrillator directly onto the heart by doing a sternotomy and opening the pericardium...it is called an open epicardial lead placement...the ep will then assist in the or by configuring the pacemaker...the ep doesnt scrub in or anything, just offers his/her knowledge of ep, which the meathead surgeon usually knows nothing about