Validation of Noninvasive Epi- Endocardial Electrocardiographic Imaging Accuracy Using Right Ventricular Endocardial Pacing

Abstract

Invasive electroanatomical mapping of polymorphic and unstable ventricular arrhythmias is a complex and laborious task. Noninvasive epi-endocardial ElectroCardioGraphic Imaging (ECGI) is a novel beat-to-beat mapping technique. The present work is a second part of single-center single-blind cross-sectional study to verify epi-endocardial ECGI accuracy. This part is particularly dedicated to investigate ECGI accuracy during right ventricular endocardial pacing followed by polygon model quality assessment and detailed analysis of cumulative effect of many different factors.Methods. 37 patients with previously implanted pacemakers were enrolled in the study. All patients underwent epiendocardial ECGI mapping (Amycard 01C EP Lab, Amycard LLC, Russia - EP Solutions SA, Switzerland) during right endocardial ventricular pacing. The data obtained from torso and ECG-gated cardiac computed tomography (Somatom Definition 128, Siemens AG, Germany) were used to create three-dimensional ventricular models. Geodesic distance between noninvasively reconstructed early activate zone on the isopotential maps and RV reference pacing site were measured to evaluate ECGI accuracy for each patient.Results. The mean (SD) geodesic distance between noninvasively reconstructed and reference pacing site was 23 (14) mm for RV epicardial models and 9 (12) for RV endocardial surface of epi-endocardial models, median (25-75% IQR) - 21 (11-32) мм and 4 (2-8) mm respectively. ECGI accuracy on RV endocardial surface of epi-endocardial models was significantly better than on epicardial models (p <0,001). At the same time, there were no significant associations between cardiac CT, pacing parameters, clinical characteristics and accuracy values.Conclusions. The main results showed a possibility of novel epi-endocardial ECGI mapping to detect RV focal arrhythmias with high accuracy (median 3 mm) and to recognize endocardial localization with high percent of probability (more than 94%) comparable with invasive electroanatomical mapping. Therefore, this study confirms sufficient accuracy of epi-endocardial ECGI mapping technology for non-invasive topical diagnosis of RV focal arrhythmias.

Noninvasive epi-endocardial electrocardiographic imaging of ventricular septal pacing

“…Further analysis included evaluation of typical morphology of paced QRS complex. All other stages of registration of multichannel surface ECG, CT and processing of non-invasive imaging data were identical to those previously published in our recent work [3,4]. Export of three-dimensional polygo-nal models in the VTK format and original multichannel ECG recordings in the specific text format was performed using software "Amycard 01C".…”

“…According to the new FRA-V algorithm, the area of early activation was determined automatically on the three-dimensional polygonal model of the ventricles as the point with the highest value of the correlation coefficient of the similarity maps (Figures 1, 2). In the same way to previous studies, the exact position of the pacing electrode in the IVS was evaluated during CT. Then the geodesic distance was measured (along the surface) between the tip of the RV electrode and the center of the early activation zone that were marked with a tag [3,4]. All study measurements were performed only on the endocardium of the epi-endocardial three-dimensional polygonal model (endo epi-endo model) in each patient.…”

“…Despite the promising prospects of this methodology, lack of information on detailed quantitative analysis of the accuracy of ECGI until recently was one of the key fac-tors limiting its use in clinical practice. In this regard studies with a detailed quantitative verification of ECGI and a thorough analysis of possible contributing factors on used algorithms for solving the inverse problem of electrocardiography allowed us to estimate its accuracy along with the facilities in topical diagnosis of focal arrhythmias [3,4]. In particular, it was shown that the accuracy of ECGI in the area of interventricular septum (IVS) was relatively low (median value 23 mm), and the clinical implementation of ECGI for preoperative diagnostics of ventricular arrhythmias was significantly limited.…”

Comparison of CARTO LAT Maps and Non-Invasive Activation Maps for Patients with Intraventricular Conduction Disturbance During Sinus Rhythm

“…The results of recent validation studies showed high precision of non-invasive electrocardiographic imaging (ECGI) for focal arrhythmia localization [1][2][3][4][5]. Successful ablation of arrhythmias and colocalization of the early activation zone (EAZ) with the pacing lead tip can be reliable methods of accuracy verification.…”

Non-Invasive Electrocardiographic Imaging in Differential and Topical Diagnosis of Ventricular Tachycardia With Ventriculoatrial Retrograde Conduction

“…Эта методика основана на решении обратной задачи электрокардиографии в форме потенциалов и позволяет с высокой точностью реконструировать эпи-и эндокардиальные электрограммы (ЭГ) и визуализировать электрофизиологические процессы на основе различных активационных карт [6]. Использование НЭФК было продемонстрировано в ряде исследований и показало достаточно высокую точность в топической диагностике желудочковых аритмий [7][8][9] и РЧА также еще раз продемонстрировало высокую точность новой методики, показанную в предыдущих исследованиях [7][8][9]. Примечательно, что другие похожие системы НЭФК [14] позволяют реконструировать ЭГ и активационные карты только на эпикардиальной поверхности сердца, тогда как электрофизиологическая информация на эндокарде в ряде случаев имеет ключевое значение для диагностики аритмий.…”