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is a left anterior fascicular block dangerous
Kalel3347 posted:
I had a ECG and was told I have a left anterior fascicular block. I have High bp (controled) and High Colesterol (controled) also told have low potasium started on perscription med for this.
CardiostarUSA1 responded:

Kudos on controlling those risk factors (BP/cholesterol) for coronary artery disease (CAD).

re: Is a left anterior fascicular block dangerous?

According to various medical literature, it's not typically dangerous in itself, though it may/can place the patient at having a slightly higher risk of requiring pacemaker implantation sometime down the road of life.

Priority-selected info is provided below.

ALWAYS be proactive in your health care and treatment. Most important, communicate/interact well with your doctor(s).

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Bundle branch block

Causes, significance and treatment

Bundle branch block (BBB) is a relatively frequent finding on the electrocardiogram.

Sometimes BBB itself needs to be treated; sometimes it indicates significant underlying cardiac disease that needs to be treated; and sometimes it has so little significance that no treatment is necessary at all....

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.


Texas Heart Institute

Bundle Branch Block


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