Ablation is used to treat abnormal heart rhythms, or arrhythmias. The type of arrhythmia and the presence of other heart disease will determine whether ablation can be performed surgically or non-surgically.
Non-surgical ablation, used for many types of arrhythmias, is performed in a special lab called the electrophysiology (EP) laboratory. During this non-surgical procedure a catheter is inserted into a specific area of the heart. A special machine directs energy through the catheter to small areas of the heart muscle that causes the abnormal heart rhythm. This energy "disconnects" the source of the abnormal rhythm from the rest of the heart. It can also be used to disconnect the electrical pathway between the upper chambers (atria) and the lower chambers (ventricles) of the heart.
Surgical ablation procedures used for treating atrial fibrillation can be "minimally invasive" or traditional "open" surgery and may be combined with other surgical therapies such as bypass surgery, valve repair, or valve replacement. Surgical ablation procedures include:
The Maze procedure. During this traditional open-heart surgical procedure, the surgeon makes small cuts in the heart to interrupt the conduction of abnormal impulses and to direct normal sinus impulses to travel to the atrioventricular node (AV node) as they normally should. When the heart heals, scar tissue forms and the abnormal electrical impulses are blocked from traveling through the heart.
Minimally invasive surgical ablation. Unlike traditional heart surgery, there is no large chest wall incision and the heart is not stopped. These techniques utilize smaller incisions and endoscopes (small, lighted instruments that contain a camera).
The modified Maze procedure. The surgeon uses a special catheter to deliver energy that creates controlled lesions on the heart and ultimately scar tissue. This scar tissue blocks the abnormal electrical impulses from being conducted through the heart and promotes the normal conduction of impulses through the proper pathway. One of four energy sources may be used to create the scars: radiofrequency, microwave, laser, or cryothermy (cold temperatures). The modified Maze procedure involves a single incision in the left atrium.
In addition to re-establishing a normal heart rhythm in people with certain arrhythmias, ablation therapy can help control the heart rate in people with rapid arrhythmias, and potentially reduce the risk of blood clots and strokes.