Localization of Manifest Right Posteroseptal Accessory Atrioventricular Pathway With the Help of the Spatial Vector-Electrocardiography

Abstract

We have researched the infringements of diffusion of excitation in myocardium of ventriculars with functioning right posteroseptal accessory atrioventricular pathway (RPAP) with the help of the spatial animation vector – electrocardiography (3D-VECG). The information got by us, can be used for RPAP localization during operations. We examined 18 patients aged 12-52 (middle age 25,3) having manifest of preexcitation ventriculars syndrome. Besides standard methods of examination: ECG-12, transesophageal and endocardial pacing, all patients were examined by the original methods 3D-VECG. We used the orthogonal system of electrode leads macfee-Parungao in modification E. A. Ozola for registration and analysis of electric heart activity. ATES MEDICA (Italy) computer system was used for registration, viewing and the analysis of the vector-electrocardiogram (VECG). After registration of biopotentials of heart we looked through the correction projections of integral electric vector of heart to axes X, Y, Z. Then the most informative cardiac cycle was chosen and processed by the original program in Mathcad 7. As a result of researches we received VECG, including animated, that reflects the character of the infringements of diffusion of excitation in myocardium of ventriculars at various RPAP localization. Interpretation of our results was realized in accordance with the dipoles theory of cardiac electrogenesis and the concept of Grant-Penaloza-Tranchesi. All accessory pathways were divided into three groups in accordance with the results of RFA: 7 patients with RPAP, 3 – left posteroseptal accessory pathways, 4 – right inferior accessory pathways, 4 – right free-wall in the inferior site. We have established that 3D-VECG is able to find localization accessory pathways in the topographical difficult posteroseptal area before RFA. Coincidence of zones of localization on 3D-VECG with results of RFA has made 92,8%. Thus, 3D - VECG is a sensitive method for localization RPAP within the limits of one anatomic zone of localization. In some cases 3D – VECG is only sensitive noninvasive method of localization accessory pathways in the posteroseptal area.