Carolinas Core Concepts Core Concepts in EM; a repository for Carolinas lecture summaries.

9Aug/111

Littmann’s EKG Course: The QRS Complex

  • LBBB makes most EKG's unreadable, except in those where the ST is concordant.  Watch for STEMI!

    LBBB + STEMI

    Inferior STEMI seen in II, III, aVF in a patient with LBBB. ST segments should not be concordant!

  • Electrical alternans can be easy to miss but may indicate an underlying effusion.

    Electrical Alternans

    Electrical Alternans in an HIV patient with an effusion.

  • The finding of marked axis deviation, RBBB, and prolonged PR interval is concerning for trifascicular block.  In a patient with unexplained syncope this is a potentially lethal finding; admit for emergent pacemaker.
    Trifascicular block

    RBBB, left posterior fascicular block, and prolonged PR: trifascicular block in a patient with syncope. Emergent indication for pacemaker!