Corrected QT Interval (QTc)
Corrects the QT interval for heart rate extremes (choose from Bazett, Fridericia, Framingham, Hodges, or Rautaharju formulas).
Ensure the QT interval measurement does not mistakenly include a U wave. If it does, re-measure, recalculate, and consider potential etiologies of U waves.
If there is no U wave, consider common causes of a prolonged QT interval, including:
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Electrolyte abnormalities.
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Intrinsic cardiac causes.
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Central causes.
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Medications.
If a short QT interval is observed, confirm measurement accuracy and consider short QT syndrome (see Facts & Figures).
Management depends on the specific etiology of a prolonged or shortened QT interval. In general, minimize the use of QT-prolonging medications in patients with QT prolongation and only use them after a thorough risk-benefit assessment.