P3750Efficiency of electrocardiographic algorithms in management of idiopathic outflow tract ventricular arrhythmias in children

Abstract

Abstract Introduction Ablation of idiopathic ventricular arrhythmias (IVA) originating in left ventricle outflow tract (LVOT) are more challenging as compared to right ventricle outflow tract (RVOT). In recent years, several ECG algorithms predicting the site of origin (SOO) of arrhythmia for adult population have been published. There is a sparse information on their diagnostic performance in children. Purpose The aim of this study was to validate two algorithms: 1) Novel TZ index, 2) V2S/V3R and their combined application in children for predicting the appropriate SOO of IVA. Methods Two groups of children without structural heart disease, thorax anomalies and normal QRS complexes during sinus rhythm were included in the study: 1) patients with IVA with inferior axis who underwent successful RFCA using the 3D-electroanatomical system, 2) patients with paced or mechanically-induced QRS complexes from LVOT or RVOT during other procedures. ECGs were analyzed in a specially developed software for analyzing the amplitude of the QRS complex waves. Semi-automated measurements of amplitudes of QRS complexes and calculations were carried out for 2 published algorithms: 1) Novel TZ index, 2) V2S/V3R. The results of their separate and combined use were compared with SOO of acute successful RFCA and mapping or spot of pacing. Results 108 PVC morphologies (68 from the RVOT and 40 from LVOT) from 74 pediatric patients (age: 14.0±2.9, 39 female) were included into the study. The algorithm V2S/V3R predicted left-sided SOO with a sensitivity and specificity of 94%. Novel TZ-index showed sensitivity of 89% and specificity of 84%. Combined use of Novel TZ-index+V2S/V3R showed high sensitivity (92%) and very height specificity (97%) of the LVOT SOO prediction Conclusion Both algorithms allowed accurate, simple and precise identification of SOO of RVOT/LVOT IVA in children. The combined use of those algorithms may facilitate additional pharmacologic treatment, omitting RVOT mapping with direct mapping LVOT, performance of the procedure by experienced operator.