Hyperacute T waves in inferior leads as a dynamic sign of evolving STEMI

Introduction: Electrocardiogram is a commonly used tool in the diagnosis of acute myocardial infarction. Among ECG signs of acute cardiac ischemia, tall and broad-based T waves, called hyperacute T waves, may be the earliest and the only ECG sign of ST-elevation myocardial infarction (STEMI).Objective: To underline the importance of early recognition hyperacute T waves as one STEMI equivalent in order to prevent further damage to the myocardium by appropriate treatment.Case report: A 65-year-old female was admitted to the emergency department for chest pain. An electrocardiogram revealed the presence of tall and broad-based T waves in inferior leads, T-waves inversion in D1-aVL and ST-segment depression in V4-V5-V6. Aspirin, ticagrelor, and sublingual nitroglycerin almost fully resolved the patient's chest pain which coincided with the resolution of the tall T waves and improvement of ST-segment depression in V4-V5-V6. Approximately 15 min later, the patient experienced recrudescence of chest pain followed by severe hypotension and sinus bradycardia. Emergent coronary angiography disclosed a complete thrombotic occlusion in the mid-right coronary artery (RCA). Balloon angioplasty and placement of a drug-eluting stent in RCA was performed.Conclusion: Hyperacute tall and broad-based symmetric T waves are transient and thus uncommonly seen, but they can be the very first ECG evidence of total coronary occlusion and transmural ischemia. Early recognition of this ECG pattern is crucial to ensure diagnosis and optimal treatment of patients with STEMI, which consist in immediate reperfusion by primary angioplasty.