Catheter Ablation helps lessen atrial fibrillation symptoms. The procedure is conducted via catheter and helps prevent the heart from receiving abnormal signals.
In a catheter ablation procedure, a catheter is guided to the heart through a blood vessel. The catheter delivers energy to destroy cells within the heart that send abnormal signals. Your doctor may recommend you a Left Atrial Ablation procedure, an AV Node Ablation procedure, or a Maze procedure, depending on the type of AFib you suffer from and whether or not you can take medication for your condition.
Technically, ablation refers to destruction of tissue. When we do cardiac ablation, we are selectively targeting short circuits or sources of abnormal electrical impulses that cause rapid heart beats. An ablation procedure can be relatively simple or complex. An ablation is done in the electrophysiology or EP lab. Depending on the procedure, you may receive simple sedation or general anesthesia. Catheters are advanced through a vein in the leg to the heart. The ablation itself is accomplished by either burning or freezing small areas of heart tissue with one of these catheters. Some ablation procedures are done strictly as an outpatient and you go home the same day, whereas other oblations require that you stay overnight. Risks of the procedure are low in general, but depend on what area of the heart is being ablated.
Cardiac ablations target only abnormal heart tissue. There is no significant impact on heart function.
Atrial fibrillation or AFib usually is triggered by very rapid electrical impulses coming from the pulmonary veins. These are veins coming from the lungs that drain into the left atrium. There is heart muscle type cells in those veins with different properties than the rest of the heart that allow such rapid electrical activity. When we ablate atrial fibrillation, we either burn or freeze around the openings of those pulmonary veins to make a firewall that keeps those impulses from irritating the heart. In many situations, that is all that is required. However, in more advanced atrial fibrillation, there may be ablation required in other areas.
AFib ablation is usually done with general anesthesia. Simple pulmonary vein isolation typically takes about two hours, but can go on significantly longer if additional ablation is required.
In general, you can expect an 85% reduction in atrial fibrillation. This may be a complete elimination or just a reduction in the amount of atrial fibrillation. Recurrences can be due to triggers coming from outside the pulmonary veins or may be due to reconnection of the pulmonary vein muscle fibers to the left atrium. This can require a repeat ablation procedure depending on the severity of recurrence.
Major complications are rare, but can be serious. The most concerning are stroke, atrial esophageal fistula and death. Strokes are usually caused by blood clots in the heart, and therefore we prescribe anticoagulants around the time of ablation. A risk peculiar to atrial fibrillation ablation is damage to the esophagus, which passes directly behind the left atrium. In rare cases, a hole can form between the atrium and the esophagus which can be lethal. We therefore monitor the esophageal temperature during ablation and prescribe acid blockers afterwards to protect the esophagus.
Expect to stay overnight. You will be at bed rest for three hours after the ablation. You can be up and around after that, but avoid heavy exertion for one week. While we do the ablation to prevent atrial fibrillation, the actual ablation itself causes irritation and in the first week in particular it is not uncommon to have recurrences of irregular heartbeat or even atrial fibrillation. Depending on our risk assessment, we may or may not therefore prescribe an antiarrhythmic drug. It is common to have mild chest discomfort for the first 2 or 3 days. We frequently prescribe an anti-inflammatory medication such as prednisone to prevent this. We also treat with antacid therapy for 1 month to protect the esophagus. It is common to have some bruising at the puncture sites. Usually it is fairly local, but it can extend a good way down to the knee on occasion. That in and of itself is not alarming. Progressive pain or swelling at the puncture sites is more concerning as it could represent continued bleeding. Late onset of chest pain or pain on swallowing requires immediate attention to prevent atrial esophageal fistula.