Atrial Repolarization Mimicking Ischemia on ECG: Don't Miss the Ball
David T Zhang1, Mark B Hellerman1
1Division of Cardiology, Department of Medicine, Stony Brook Medicine, Stony Brook, New York, USA.
Case Summary:
A 54-year-old woman presented with syncope and substernal chest pressure following emotional stress. Electrocardiography demonstrated diffuse ST-segment depressions with ST-segment elevation in aVR and V1, raising concern for subendocardial ischemia. Serial troponins were negative and coronary computed tomography angiography revealed normal coronary arteries. The findings were attributed to prominent atrial repolarization (Ta wave) contamination of the ST-segment.
Take-Home Messages:
The "hidden soccer ball" heuristic provides a practical visual tool to distinguish prominent atrial repolarization from ischemic ST-segment changes. Consider atrial repolarization when apparent ST-segment abnormalities arise in states of increased sympathetic tone.
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