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Atrial Flutter with Variable Block



  • Atrial flutter is typically a regular, narrow complex tachycardia with 2:1 or even higher levels of AV block. In some patients the AV block is variable; this may be either idiopathic or in the context of complete heart block.
    • Look For

    • Irregular rhythm
    • Saw-toothed baseline ‘flutter’ waves at ~300bpm
    • Variable atrioventricular block (inconsistent number of flutter waves between QRS complexes)
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 Mangrum JM, DiMarco JP. The evaluation and management of bradycardia. New England Journal of Medicine. 2000 Mar 9;342(10):703-9.