Giant negative U waves during acute myocardial infarction and ischemia
T Yamaguchi1, M Yotsukura, S Kabasawa
1Second Department of Internal Medicine, Kyorin University School of Medicine, Tokyo, Japan.
Abstract:
Giant negative U waves transiently appeared in a patient with acute myocardial infarction (AMI). During hospitalization, these giant negative U waves (0.3-0.5 mV) were observed in leads V2 through V4 of the electrocardiogram (ECG). The waves disappeared 10 days after hospitalization, but reappeared during a treadmill exercise test 3 weeks after the onset of AMI. The same waves were detected again when the patient was admitted for angina pectoris 3 months later. Since these giant negative U waves appeared concomitant with myocardial ischemia, ischemia seems to be their cause. To our knowledge, there are no previous reports on reproducible U waves like those seen in this patient.
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