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    Is left anterior fascicular hemiblock serious
    Rajesh19 posted:
    Can anyone help me with this query . I had an ECG done yesterday and it says :
    Normal sinus rhythm
    Left anterior fascicular block / left anterior hemiblock
    Abnormal ECG
    Is this serious ? What is the prognosis ?
    cardiostarusa1 responded:

    "Left anterior fascicular block / left anterior hemiblock"

    "Is this serious? What is the prognosis?"

    General info-only

    Causes, significance and treatment

    The Hemiblocks

    The left bundle branch itself divides into two major branches - the anterior and the posterior fascicles. Sometimes block can occur in just one of these fascicles. Such blockage is referred to as a hemiblock, or a fascicular block. (Note that the right bundle branch does not divide into discrete fascicles.)

    When blockage is in the anterior fascicle, left anterior hemiblock (or left anterior fascicular block) is said to be present; whereas if the blockage occurs in the posterior fascicle, then left posterior hemiblock (or left posterior fascicular block) is said to be present.

    In general, finding a hemiblock should trigger a search for underlying heart disease. Often none is found, in which case the hemiblock can be ignored.

    Best of luck down the road of life.

    Take care,


    WebMD member (since 8/99)




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