[Transvenous ablation of the conduction under fluoroscopic control in a case of refractory supraventricular...

Transvenous ablation of atrioventricular (AV) junction is an accepted method for treatment of refractory supraventricular arrhythmias. In the classic method the proper position of the ablation electrode is based on registration of the potentials of the conduction system. However according to Bredykis et all. Localization of the catheter is also possible under fluoroscopic control. The study presents a 67-year old patient with recurrent supraventricular tachycardias. Repeated bouts of arrhythmia, refractory to various antiarrhythmic drugs, caused severe hemodynamic consequences. Several cardioversions were performed for arrhythmia termination. Electrophysiologic study using transesophageal pacing showed a concealed accessory pathway conducting only in retrograde direction and the patient was designated for transvenous ablation of AV junction. The specially developed 6F USCI electrode with enlarged tip was used. The catheter was introduced into the right ventricle under fluoroscopic control and then slowly withdrawn until the tip was placed within the tricuspid valve at the border of atrium and ventricle. Cathodal pole of the defibrillator was connected with the electrode. Then the procedure was similar to the classic ablation. Single 200 joules DC shock caused complete AV block. No complications were seen during and after the procedure. A permanent cardiac pacemaker was implanted at the 4th day after ablation. The patient was doing well, without medication and no arrhythmias were observed during the 9 month period. The AV block persisted stable, also retrograde conduction was absent.