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.