Stychynskyi S. Atrial tachycardias: electrophysiological diagnostics, catheter treatment

The dissertation is devoted to the treatment of focal atrial tachycardias - widely distributed disturbance of cardiac rhythm which can lead to the serious complications. It is based upon the data of 92 catheter procedures performed in 82 patients with atrial tachycardias during the period from 1998 to 2006. The group of the assesment of the efficacy of the developed methods includes the data of 26 catheter procedures performed in 25 patients in 2007 and 2008. The basic problems of diagnostics and treatment of atrial tachycardias were considered. The ECG criteria of topical diagnostics of the arrhythmia focus, which allow determining its localization to within several centimeters, were developed. The characteristics of induction and termination of these arrhythmias were examined. The criteria of differential diagnostics, that allow distinguishing focal atrial tachycardias from the other SVTs, were given. Qualitative and quantitative analysis of endocardial electrograms during tacycardia were made. Comparative characteristics of different types of endocardial mapping in atrial tachycardia were cited. The correlations of local electrogram and P wave that are appropriate for radiofrequency applications were defined. Energy characteristics of radiofrequency applications which are sufficient for arrhythmia elimination and at the same time safe with relation to undesirable damage of atria were determined. Prophylactic measures, which take into account different potential risk factors, were developed. On the basis of the results of the research a method of catheter treatment of atrial tachycardias, which allowed eliminating arrhythmia in 100% of cases with no complications, was developed.