Scenario: This ECG (lead II) was obtained in a 4-month-old infant with transposition of the great arteries who had surgical repair for arterial transposition and ventricular septal defect. The postoperative course was complicated by occlusion of both the right and circumflex coronary arteries. Following surgical repair of both coronary arteries as well as a mitral valve repair due to a papillary muscle infarct, the patient returned to the intensive care unit. The patient was receiving continuous sedation. At the time of this recording, the patient’s heart was being paced via epicardial wires, using a temporary external pacemaker. The atrial demand rate was set at 140 beats per minute (bpm). This patient’s pacemaker was configured as AAI, with the first letter indicating chamber paced (A), second letter chamber sensed (A), and the third letter indicating response to the sensed event (I). The bedside...

You do not currently have access to this content.