Terminal electrocardiographic changes in brain-dead patients

We analyzed ECGs of 18 brain-dead patients from the time of termination of ventilation until cessation of electrocardiographic activity. Gradual slowing of the atrial mechanism was followed by AV block or a gradually slowing junctional escape rhythm. Despite progressive failure of atrial and junctional pacemakers, none had a ventricular escape rhythm. There were three terminal rhythms: (1) atrial activity only, (2) slow junctional rhythm or sinus bradycardia, or (3) ventricular tachycardia (VT). A prolonged QT interval, corrected for rate, was related to later development of VT. One hypothermic and three euthermic patients had J waves.