Three-dimensional 12-lead ECG-based electrocardiographic imaging in cardiac resynchronisation therapy recipients – Validation against non-contact electroanatomical mapping

Background: The cardiac isochrone positioning system (CIPS) is a novel electrocardiographic imaging (ECGi) modality that integrates 12-lead ECG, body surface imaging and cardiac magnetic resonance (CMR). Objective: To validate CIPS against non-contact electroanatomical mapping (EAM) with respect to left ventricular (LV) activation patterns in patients undergoing cardiac resynchronisation therapy (CRT). Methods: CRT recipients (n=16; LBBB in 12, nonspecific intraventricular conduction delay [NICD] in 4) underwent ECGi (CIPS) and EAM (Ensite, Abbott) during intrinsic and right ventricular (RV) pacing. Three independent electrophysiologists were asked to score the accuracy of early and late LV activation using CIPS against EAM (62 maps). Results: The latest activated segment on EAM were lateral, posterior or anterior LV segments (50%, 44% and 6%, respectively). Using expert adjudication, CIPS correctly identified late LV activation during intrinsic rhythm in 13/16 (81.3%) patients (kappa coefficient: 0.88 (95% confidence intervals [CI]: 0.73–1, p