Introduction: Recent achievements in noninvasive electrocardiographic (ECG) imaging allowed its extensive use in diagnostics and treatment of different arrhythmias. This study aimed to identify sources of initiation and maintenance of atrial fibrillation (AF) by means of surface ECG based mapping technology combined with CT scan or MRI and to evaluate results of ablation guided by these maps.
Methods: We applied noninvasive mapping using 240-lead ECG combined with CT scan or MRI based anatomy (Amycard LCC) to 10 patients (6 male/4 female) with persistent AF (mean continuous AF duration 4±2 months). Windows with spontaneous pauses during AF were selected for mapping before procedure. We evaluated electrical activity in the left, right atrium and atrial septum using specific algorithm. In 9 patients radiofrequency (RF) ablation was made at the sites of sustained circular electrical activity (rotors) followed by antral pulmonary veins (PV) isolation. One patient underwent Maze IV procedure due to thrombus in left atrial appendage.
Results: During evaluation of electrical activity in the left and right atrium we found from 2 to 4 simultaneously coexisting rotors. RF application in this areas resulted in alteration of frequency or direction of electrical activity registered at CS or Lasso catheters. Targeted ablation terminated AF and maintained sinus rhythm in 7 patients (70%). Mean RF application time was 26±18 minutes. In 3 patients (30%) we registered prolongation of arrhythmia cycle length but its termination was achieved only after pharmacological or electrical cardioversion.
Conclusions: Initial experience with noninvasive ECG imaging using 3D-4D mapping system combined with CT scan or MRI shows its clinical utility, feasibility to provide noninvasive characteristics of arrhythmogenic areas and to increase effectiveness of interventional AF treatment.