Emergency Treatment of Arrhythmias

ByL. Brent Mitchell, MD, Libin Cardiovascular Institute of Alberta, University of Calgary
Reviewed/Revised Sep 2024
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    Diagnosis of specific arrhythmias, although often straightforward (eg, clear from the ECG), sometimes requires more detailed evaluation, including detailed history, physical examination, and sometimes ancillary testing. If the specific arrhythmia cannot yet be identified, arrhythmias can still be divided into one of the following categories:

    • Wide-complex tachycardia (QRS > 0.12 msec)

    • Narrow complex tachycardia

    • Bradycardia

    Patients with arrhythmias may also be hemodynamically stable or unstable (ie, poorly perfused, as with hypotension, suspected myocardial ischemia, or altered consciousness). Pending diagnosis of the specific arrhythmia, patients who are hemodynamically unstable or need urgent treatment can be treated with the following temporizing measures:

    • Tachycardia with hemodynamic instability: Cardioversion

    • Wide complex tachycardia with hemodynamic stability: Treat as for ventricular tachycardia

    Approach to Cardiac Arrhythmias

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