The revolutionary pioneering step in the percutaneous curative treatment of atrial fibrillation (AF) was taken by Haissaguerre in 1994. The most important point in the emergence of this treatment initiative stems from the fact that a physiopathological feature of AF is well known. As it is known, myocardial tissue must have a critical mass in order to fibrillate. AF does not occur if there is no clinically critical myocardial tissue in which fibrillation can occur and continue. Based on this information, Haissaguerre and his colleagues divided the right atrium into small compartments where AF could not continue by drawing a line between the inferior and superior vena cava within the right atrium and creating some lines perpendicular to this line. This technique consisted of a version of the surgical Maze operations that have been performed for years, performed with a catheter in the right atrium. However, it was important as it was the first sign that this type of procedure began to be performed percutaneously. The success rate of ablation procedures performed with linear ablation in the right atrium in the treatment of AF remained around 10% even in selected cases. In later years, attention turned to the left atrium as it was understood that the major role in the formation and maintenance of AF was played by the left atrium. At the end of the nineties, the same team discovered that pulmonary veins play a very important role in the formation of AF and turned to the treatment of AF by ablation of focal foci within the pulmonary veins. Although the focal ablation method of the pulmonary veins gave much more successful results than the linear ablation of the right atrium, the technique required revision due to the high risk of pulmonary vein stenosis. The next part of the story continues with dizzying developments in new techniques, new devices, increasing success, and the application of the procedure in more patients.
We started AF ablation procedures in 2005. The most popular technique at that time (and it is still the most frequently used technique with some revisions) was to create circular ablation lines around the pulmonary veins accompanied by three-dimensional imaging and navigation systems. Pappone and his colleagues were reporting their experiences on thousands of patients with this circular ablation method, which they published in the mid-2000s. Special in these series Success rates reaching 70-80% were reported, especially in patients with paroxysmal AF. Our application was based on the method of Pappone et al. First of all, patients with a left atrial diameter preferably below 4.5 cm, who were not of advanced age (< 65 y) and who had paroxysmal AF were candidates for the procedure. The absence of significant accompanying structural heart disease was also among the required conditions. These patients, who did not respond to drug treatment trials and were informed about the procedure, were included in the AF ablation program. In patients for whom the procedure was planned, multi-slice computed tomography was used to image the left atrium and the pulmonary veins opening to the left atrium. Transesophageal echocardiography showed that there was no thrombus in the left atrium. On the day of the procedure, patients were deeply sedated with midozolam and, if necessary, propofol. Femoral vein punctures were performed and a diagnostic electrophysiology catheter was first placed into the coronary sinus. In our anatomical procedure approach, this catheter showed us the lower edge of the interatrial septum. The pigtail catheter, which was advanced to the aortic root via femoral artery puncture, allowed us to mark the aortic position. An inter-atrial septum puncture was performed using a standard technique, and anticoagulation was performed with high-dose unfractionated heparin following placement of an SL0 or SL1 long sheath in the left atrium. To determine the location of the esophagus and mark it on the 3D imaging screen, a bipolar temporary pacing catheter was sent nasally to the stomach and retracted. The time from the patient's arrival at the laboratory to the completion of the above procedures was approximately 1.5 hours. Then, three-dimensional virtual images of the left atrium were obtained (with the Ensite NavX system) using any ablation catheter. Meanwhile, the pulmonary veins were entered with an ablation catheter and the relationship of the pulmonary veins with the left atrium was marked on the virtual display screen. The accuracy of the virtual images was tested by comparing the virtual images with the real images obtained by multi-slice tomography. Then, 2 wide, circular ablation lines were created, first around the left 2 pulmonary veins, then around the right 2 pulmonary veins, away from the mouth of the pulmonary veins. Meanwhile, use a 4 mm or 8 mm traditional ablation catheter or an irrigated ablation catheter. ether was used. Then, both circular ablation lines were combined with a linear ablation line at the atrium ceiling. In the majority of patients, another linear ablation line was created between the mitral isthmus and the left circular ablation line. However, in recent years, it has become clear that this technique, which is a pure anatomical approach, needs to be modified further. Namely, the procedure is based on the principle of isolating the pulmonary veins from the atrium tissue. However, after the process, it is not checked whether this insulation is complete. Confirming that the pulmonary veins are disconnected from the atria by placing a spiral catheter in the pulmonary vein openings after the procedure in parallel with the flow in the world has become a part of AF ablation. In this way, the success of the procedure increases and it is possible to see the results of the procedure immediately.
Atrial fibrillation ablation is a difficult, time-consuming, and troublesome process for the patient and the team performing the procedure. Therefore, patients must be selected well and informed about success and complications. When selecting patients, it should not be forgotten that the best results will be obtained from paroxysmal AF cases that are still resistant to medications. Procedure success is low in persistent and especially perminant AF. Additionally, the AF ablation technique described above is not sufficient in these patients. Additional ablation lines in the left and right atrium, or even ablation targeting complex fractional electrograms, need to be added to the technique. On the other hand, AF ablation was not a procedure without complications. Even in the best centers in the world, a major complication rate of around 5% is reported. Although the rates of pulmonary vein stenosis and atrio-esophageal fistula specific to atrial fibrillation ablation decrease as the applied techniques are refined, complications such as cardiac tamponade, left atrial flutter, and thromboembolic complications still continue to be serious procedure risks.
The aim of atrial fibrillation ablation is to eliminate AF attacks without the need for medications. Even if this goal is not achieved, at least reducing the frequency and severity of attacks with medications is an important achievement. However, to fully evaluate the response to AF ablation, it is necessary to wait 2-3 days after the procedure and make a decision. After this blind period, it is decided whether the patient will benefit from AF ablation. It is better to give. The aim of AF ablation is to eliminate all symptomatic and asymptomatic AF attacks. In practice, the disappearance of symptomatic AF attacks often gives us relief as a clinical response. But in such a case, it should not be forgotten that the patient still needs to take oral anticoagulants according to the thromboembolic risk scoring (CHADS2 score).
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