Catheter Ablation This catheter-based procedure is designed to find the areas in the atria that are causing atrial fibrillation (afib) to occur and spread ...
This catheter-based procedure is designed to find the areas in the atria that are causing atrial fibrillation (afib) to occur and spread throughout the atria. The doctor looks at various areas within the top chambers of the heart to find the source of the abnormal electrical impulses. Often these impulses come from an area in and around the pulmonary veins in the left atrium (the four large veins that bring blood back to the heart from the lungs).
Your doctor inserts flexible catheters into blood vessels in the groin and under the clavicle (collarbone) and uses a fluoroscope (similar to an X-ray machine) to monitor the catheter as it is moved to the heart.
In order to get the catheters into the left atrium, one or two punctures (transseptal puncture) in the atrial septum are necessary. Once the catheters are in place, the doctor will start to record the electrical signals from the heart from sensors at the tip of the catheters and map the pulmonary veins as well as other areas in the atrium. This is done with the aid of navigational tools and computers constructing a 3-D image of the heart.
Once the source is located, the radiofrequency energy (electrical current) will be passed through the catheter and heat the tissue at the tip of the catheter. This will inactivate or scar the tissue. Your doctor may refer to these as lesions or burns. The doctor may create a ring or circle around the pulmonary veins that enter the left atrium, which is called pulmonary vein isolation (PVI).
For patients with paroxysmal afib, PVI may be all that is necessary (especially if there is no other heart disease); however, some patients (particularly if afib has become more persistent) need more lesions targeted at areas that allow each afib episode to continue for long periods of time. The goal of the additional ablation is to change or modify the atrial tissue (substrate) so that can no longer happen.
A surgical ablation can be done as a standalone procedure in a less invasive surgical approach, or together with an open-chest procedure for another medical reason (such as a coronary artery bypass or heart valve replacement).
This procedure is done with either the use of radiofrequency energy, ultrasound energy, microwave energy or cryoablation (creating an ablation by freezing tissue) applied to the outside of the atria around the pulmonary veins.