An Unexpected ECG Finding in a Teen with Chest Pain
A 17-year old girl with a history of asthma, migraines, postural orthostatic tachycardia syndrome, hypermobility, gastroesophageal reflux and gastroparesis status post gastric pacemaker placement a year and a half prior presented to the ED with an acute onset of chest pain and shortness of breath. The symptoms started a few hours prior to arrival and had resolved en route to the hospital after administration of Albuterol by Emergency Medical Services for shortness of breath. Upon arrival to the ED she denied chest pain, palpitations, cough, shortness of breath, or fever. Vital signs showed a heart rate of 70 beats/ minute, respiratory rate of 16/minute, blood pressure of 118/60 mmHg, temperature of 36.7°C, and an oxygen saturation of 100% on room air. On exam she was alert and in no distress. Her lungs were clear with normal respiratory effort. She had no reproducible chest pain with palpation. Heart tones were regular, no murmur was appreciated, and she had strong pulses and brisk capillary refill. Her abdominal exam was notable for a gastric pacemaker palpated in her left lower quadrant. The remainder of the physical exam was unremarkable. An ECG was obtained (Figure 1) given her history of chest pain and was notable for sinus bradycardia to 48 (of note, prior Holter monitor recorded low heart rates in the 40 s, and previous ECGs with heart rates in the 50 s), early repolarization (a normal variant), and asynchronous spikes lasting a total of 2 seconds...