Health Resource Center
Arrythmia Ablation
Aug 21st 2008
The normal heart beat is controlled by rhythmic
stimulation of the heart by specialized tissue that acts as a “natural
pacemaker” followed by conduction down a series of “wires” which spread that
electrical signal to the chambers of the heart. How this signal
originates and conducts determines how the heart beats. Both the heart
rate and the timing of the contraction of the various chambers of the heart are
determined by this electrical system.
Many abnormal rhythms
of the heart
(arrhythmias)
are caused by inappropriate electrical stimulation of the heart. Many of
these occur because of “abnormal wiring” or because of an abnormal stimulus to
contraction by a small amount of tissue that functions electrically in an
abnormal way. Why some individuals experience arrhythmias is complex and
in many cases not well understood. The electrical system of the heart is
very complex and the types and causes of arrhythmias are too lengthy to discuss
in detail here. Although there are many treatments for arrhythmias, many of
these abnormal rhythms can be treated with ablation. Simply put, ablation
is a technique whereby the abnormal wiring or tissue is interrupted, destroyed
or isolated from the remainder of the heart tissue, thereby “curing” the
arrhythmia. Many patients following ablation therapy require no further
medical therapy. Not all arrhythmias can be treated in this manner.
Arrhythmia ablation is a complex procedure.
Arrhythmia ablation is not considered surgery although there are some surgical
procedures that also “cure” arrhythmias. Although there are many types of
ablation techniques, the general concept is that a long thin wire or series of
wires (called catheters or electrodes) about the thickness of a strand of
spaghetti is inserted into a vein, usually in the groin or neck, and guided to
the heart utilizing x-rays. They are then utilized to detect the source
of the abnormal rhythm or the abnormal “wiring”, and are placed into or near
the part of the heart where the abnormal rhythm is likely to start. These
electrode catheters then apply various types of energy that generate energy,
usually heat, and “burn” the source of the abnormal rhythm and destroy it or,
in some cases, a series of “burns” that isolate the source of the arrhythmia
and prevent it from conducting to the heart muscle and causing abnormal
contraction. There are other ways the tissue can be ablated such as
“freezing” but the results are generally the same. There are many types
of ablation treatments with the details of how any procedure is done dependent
on the cause and type of the arrhythmia. This is an oversimplification by
necessity, as some ablation treatments can be quite complex, particularly a
newer procedure which is utilized to treat
atrial fibrillation. Whether any particular rhythm is likely to
be treatable with ablation therapy can only be determined after a careful
evaluation by your physician and usually an electrophysiologist, subspecialists
that deal with rhythm disturbances of the heart.
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