Po-04-053 out-of-hospital cardiac arrest associated with early repolarization

Early repolarization syndrome (ERS) is characterized by J-point elevation presenting as slurring or notching of the terminal part of the QRS complex. Of the several congenital and acquired disorders that encompass J-wave syndromes, ERS has been linked to increased risk of developing polymorphic VT and idiopathic VF that can lead to sudden cardiac death. To describe a patient who presented after a cardiac arrest with initial ECG criteria consistent with Type III ERS who recieved a dual-chamber ICD. n/a We present a case of a 42-year-old man without any prior history that presented to the emergency room after successful resuscitation from out-of-hospital cardiac arrest due to VF. After noticing agonal respiration during early morning hours, his wife called emergency medical services (EMS) and promptly performed cardiopulmonary resuscitation. Upon arrival, EMS found the patient to be in VF. He was shocked once by an automatic external defibrillation leading to ROSC with restoration of sinus rhythm. In the ED, his initial vitals were 122/93 mmHg, 104 bpm, 95% oxygen saturation on room air, and temperature of 36.4 °C. He denied any family history of sudden cardiac death. Wife reported prior history of nocturnal agonal respirations. Initial diagnostic work-up was significant for a leukocytosis of 19,000 and serial high-sensitivity cardiac troponins of 130, 305, and 364 with a 0/3-hour delta change of 234. A12-lead ECG upon presentation is shown in Figure 1 without previous ECGs available for comparison. An emergent coronary angiography was performed which revealed no significant coronary obstruction or anomaly. With both his ECG findings and a Shanghai Score of 7, a diagnosis of Type III ERS was highly suspected. Further diagnostic testing included a TTE showing left ventricular dysfunction with an ejection fraction of 40-45%. CMR showed no delayed gadolinium enhancement. Ultimately, a dual-chamber ICD was implanted during the admission. Follow-up ECGs revealed resolution of slurred terminal QRS complexes. He was discharged on beta blocker and low-dose losartan with close outpatient follow-up with electrophysiology. ECG changes of ERS can be dynamic and may sometimes be concealed, particularly in the setting of an out-of-hospital cardiac arrest. It is important to identify early repolarization patterns due to the adverse prognostic significance especially of Type III ERS which is associated with the highest level of risk for development of malignant arrhythmia.