Treating heart arrhythmias with ablation
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, involves a catheter being inserted into a specific area of the heart. A special machine directs energy through the catheter to areas of the heart muscle that cause the abnormal rhythm. This energy ‘disconnects’ the pathway of the abnormal rhythm. 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- heart 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 travelling 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 utilise 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 normal impulses through the proper pathway. The modified Maze procedure involves a single incision in the left atrium.
Why do I need ablation therapy?
Doctors recommend ablation therapy to treat:
- Atrial fibrillation and atrial flutter
- AV nodal re-entry tachycardia (AVNRT)
- Accessory pathways
- Ventricular tachycardia.
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 reduce the risk of blood clots and strokes.
How should I prepare for ablation?
This depends on whether it is a surgical or non-surgical ablation. These are general guidelines; your doctor or nurse will give you specific instructions.
- Your doctor may ask you to stop taking certain drugs (such as those that control your heart rate or blood thinners, including aspirin products) one to five days before the procedure. If you are diabetic, ask how you should adjust your diabetes medications.
- Do not eat or drink anything after midnight the evening before the procedure. If you must take medications, use only a small sip of water.
When you come to the hospital, you will change into a hospital gown. Leave all jewellery and valuables at home.