(The other major cause is sinus bradycardia).
Causes of Heart Block
Brief episodes of heart block are not always dangerous or even abnormal.
It disappears immediately once the triggering event has subsided and almost never requires the insertion of a pacemaker.
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There are also congenital forms of heart block.
This kind of heart block often gets worse over time, so pacemakers are often required.
If heart block is producing symptomsespecially dizziness or syncopethen treating it with a pacemaker is usually required.
Your healthcare provider can determine the degree of your heart block with anelectrocardiogram (ECG).
The higher the degree of block, the more dangerous the heart block is likely to be.
The heart rhythm produced by these subsidiary pacemaker cells is called an “escape rhythm.”
An escape rhythm, while life-saving, is often unreliable for prolonged periods of time.
In general, the higher the degree of heart block, the more likely the need for a pacemaker.
Sometimes, however, an electrophysiology study is needed to precisely localize the area of the block.
This is called a “junctional escape rhythm.”
The resulting heart rhythm is called a ventricular escape rhythm.
Ventricular escape rhythms are not only extremely slow, but they also are also notoriously unreliable.
The presence of a ventricular escape rhythm is usually considered a medical emergency.
Distal heart block tends to worsen over time.
Last Reviewed on July 18, 2019.
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