Medicine A 50 year old man presents with central chest pain. He collapsed while his ECG was being recorded. What is the cause of this ECG? A R on T phenomenon B Macro-reentrant Circuit C Early after depolarization D AV nodal Re-entry 💡 Explanation A 50 year old man presents with central chest pain. He collapsed while his ECG was being recorded. What is the cause of this ECG? ✓ Correct Answer: A. R on T phenomenon