ECG image of the month| Volume 128, ISSUE 10, P1083-1086, October 2015

The Long QT Teaser: Loperamide Abuse

      The source of a 25-year-old woman's puzzling signs and symptoms could not be determined until a search of her home yielded the answer. She had no known medical problems when she presented to the Emergency Department with a 2-week history of persistent abdominal discomfort. A routine work-up for abdominal pain was unrevealing. An electrocardiogram (ECG) showed sinus rhythm at a rate of 69 beats per minute with a QT interval of 492 ms, a corrected QT interval of 527 ms, an intraventricular conduction defect with a QRS interval of 170 ms, and nonspecific T-wave abnormalities (Figure 1). She was treated symptomatically for abdominal pain and discharged with no medications.
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      Figure 1An electrocardiogram was obtained during the patient's initial evaluation for abdominal pain of 2 weeks duration. It was notable for a prolonged QT interval of 492 ms, corrected QT interval of 527 ms, and a QRS interval of 170 ms.
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