What is Atrial Fibrillation?
Atrial fibrillation (AF) is a condition in which the upper chambers of the heart (atria) beat in a very rapid and irregular manner causing the lower chambers (ventricles) to also beat quickly and irregularly. It can be related to high blood pressure, previous heart attacks, heart valve disease or other heart disease, but in many patients no obvious cause can be found.
Atrial fibrillation can be started by extra beats that come from the "pulmonary veins" which drain blood from the lungs into the left atrium. Ablation procedures for AF entail "burns" in the regions around these veins in an attempt to 'fence off' the triggering beats to prevent the atrial fibrillation.
Tests We Do
An echocardiogram is often performed to ensure that heart structure is normal. Blood tests to check thyroid function and other measures can also be helpful.
Medication is first line therapy for atrial fibrillation. We will discuss whether it is best for you to try medications that slow heart rate, ones that attempt to prevent AF, or both. The goal of therapy is to reduce or eliminate symptoms and to address the potential risk of stroke.
Ablation is a second-line therapy that is usually reserved for patients who have highly symptomatic episodes of atrial fibrillation, which does not respond to a number of medications. Six weeks of blood thinner (coumadin or dabigatran) is required prior to the procedure as well as an injectable form of blood thinner (Fragmin) for the 5 days prior. The procedure can be performed in atrial fibrillation or in normal rhythm, but tends to be more successful in patients with intermittent, and not constant, AF. Catheters are introduced through veins in the leg and under the collar bone. These catheters are placed in the left atrium and used to create 'burns' around the pulmonary veins to stop electrical communication between the veins and the atrium. The procedure is usually done under general anesthesia and entails an overnight stay in hospital.
Unlike some of the ablation procedures we perform, ablation for atrial fibrillation is changing quickly year to year. Over the year following ablation, 70% of patients will have no further episodes of atrial fibrillation without the need for drugs. Another 10% will have no atrial fibrillation on a drug that was previously ineffective. There is a 3-month healing period during which AF may recur and patients usually remain on their medications for 2 months after ablation. If coumadin or dabigatran was required prior to planning for ablation it is continued even if the ablation is successful. If it was not previously required then it is stopped at 3 months.
As in any medical procedure, there are risks that you should be aware of. The overall risk of something bad
happening is 3-4%. The risks are:
- Life-threatening problems such as heart attack or stroke
- Injury to the esophagus
- Damage to heart requiring surgery
- Collapsed lung
- Blood vessel injury requiring surgery
- Blood clots in vein or lung
- Pain or bruising at the catheter insertion sites