Vorsorge Herz-Kreislauf




Brustschmerz: Diagnostik,
Prävention, "check-up" / Herz-Check
Herzrasen, Herzstolpern Katheterdiagnostik Klappen-Sprechstunde




Zweite Meinung Vorhofohrverschluss (occluder) Fachgesellschaften, Kongresse  
Publikationen, Wissenschaft  



Radio-Frequency Ablation (RF) in atrial fibrillation

Standard procedure in AF

The medical goal is electrical disconnection of the pulmonary veins (see images below). One of the standard procedures is radiofrequency ablation. By electrical current the pulmonary vein ostium is heated to form a scar. The cause of atrial fibrillation is thought to be electrical activity in the pulmonary veins. Thus, if a scar is formed (red-line on image below), atrial fibrillation will stop. 

Catheter Ablaltion: ablation catheter (blue, below) and diagnostic lasso catheter (light blue, above) at the entrance to the pulmonary vein. Image: Medtronic
  Pulmonary vein isolation: The red markings indicate the individual ablation areas.

These form an impenetrable barrier for the disruptive impulses. For a successful treatment it is important that no gaps remain between the point-like scars zones, only a contiguous scar line ensures a continual electrical disconnection of the pulmonary vein.

Atrial fibrillation ablation does not take place under general anesthesia, but usually under pharmacological sedation (twilight sleep). During an electrophysiological examination (EPU) a maneuverable catheter is brought into the left atrium through a vein in the groin area.
By means of special diagnostic catheters, potential atrial fibrillation can be localized and detected in the pulmonary veins. The shape of this catheter is adapted to the special anatomy of the pulmonary vein. Some types are similar to the form of a lasso (lasso catheter, see right). These catheters fit well into the pulmonary veins and are particularly suitable for measuring small currents in the pulmonary veins. This ensures that, upon completion of the ablation, electrical current no longer flows from the pulmonary veins to the atrium.

Vorhofflimmer Ablation: 3D mapping

A successful ablation therapy is dependent on exact knowledge of the pulmonary vein anatomy. Therefore, accurate images of the left atrium are now made in advance of an ablation. The preferred method for this is primarily computed tomography, but recently, magnetic resonance imaging or 3D echocardiography has been used. 
Three-dimensional data of the left atrium can then be loaded into the catheter system and serves as a guide during ablation. For this purpose, the position of the diagnosis/ablation catheter is spatially lined up with the image data of the catheter system and the three-dimensional data. The examiner can then perform the actual ablation in a virtual 3D image.
The examiner is able to view a depiction of the on-going position of the catheter in relation to the anatomic structures. In turn, modern computer technology eliminates the movements of respiration and the heart. Thus, the examiner receives a stable image and the points of ablation can be targeted securely. The computer also indicates to the examiner the places where a therapy point has already been set (FILM). This is to ensure that a consistent curve of scars is obtained. In the ablation, there are three basic principles to differentiate:
 • Radio frequency ablation
 • Cryo-ablation
 • Laser ablation
More about the topics on this page.