Abstract 15706: Non-Invasive 3D Electromechanical Cycle Length Mapping for Macroreentrant Atrial Flutter Characterization

Abstract

Introduction: Arrhythmia localization prior to catheter ablation is critical for clinical decision making. The current standard of 12-lead EKG interpretation lacks spatial specificity and is anatomically limited. Electromechanical Cycle Length mapping (ECLM) is a high frame rate, echocardiography-based frequency analysis mapping technique, that can noninvasively map, localize and characterize cardiac activation frequencies in 3D. Hypothesis: Accurate localization prior to ablation may facilitate pre-op planning, reduce procedural times and fluoroscopic exposure. In this study we access ECLM feasibility for 3D mapping and quantifying macroreentrant atrial flutter (AFL) activation rates. Methods: Four patients (N = 4; 65 ± 9yo; 3 M) presented with AFL and were referred to RF ablation. Patients underwent pre-op transthoracic ECLM with simultaneous 3-lead EKG. 3D atrial ECLM cycle length (CL) maps were rendered and areas with arrhythmic CL were identified (100-330 ms). ECLM AFL and Ventricular CLs were defined as the dominant CL of the arrhythmic region and the region that remains synchronized with the ventricular activation respectively. ECLM findings were compared against identified origins and CLs on intracardiac electroanatomic mapping (EAM). Results: ECLM successfully identified and localized the presence of atrial typical CTI flutter in all four subjects when compared against successful RF ablation. An ECLM map in a CTI AFL case is shown on Fig. 1a with the CTI circuit in the right atrium. ECLM CLs exhibited excellent agreement with both the CL of the 3-lead EKG (Atrial CL: r 2 = 0.91, Ventricular CL r 2 = 0.99) and the EAM AFL CL (r 2 = 0.92). Conclusions: ECLM can localize, map and quantify the electromechanical CLs in AFL in excellent agreement with the clinical electrical CL rates and propagation patterns obtained by clinical albeit invasive procedures, providing thus a clinical noininvasive, non-ionizing mapping tool for RF ablation planning.