Abstract 9642: Non-Invasive Magnetic Resonance Based Three-Dimensional Voltage Maps for Electrophysiology Procedure Guidance
Introduction: The association of scar on late-gadolinium enhancement cardiac magnetic resonance (LGE-CMR) with electrograms on electroanatomic map (EAM) has been investigated. We sought to quantify these associations to enable the creation of non-invasive three dimensional voltage maps (3D-VMs) based on LGE-CMR. We then tested the accuracy of the non-invasive 3D-VMs.
Methods: LGE-CMR was performed in 17 patients with ischemic cardiomyopathy before ventricular tachycardia (VT) ablation. Left ventricular wall thickness (LVWT) and scar thickness (ST) were measured in each of 20 sectors per LGE-CMR short axis plane. In the first series of 13 patients (training set), EAM points were registered to the corresponding LGE-CMR images. Multivariate linear regression analysis (MLRA) was performed to determine significant independent variables and coefficients that predict local bipolar voltage. In the remaining patients (test set), non-invasive 3D-VMs were prospectively created with the regression equations by MLRA. Invasive local bipolar voltages were then compared with the estimated bipolar voltage based on non-invasive 3D-VMs.
Results: A total of 1293 EAM points were analyzed. MLRA revealed independent associations between local bipolar voltage and LVWT, ST and scar location (P<0.001, respectively). Prospective non-invasive 3D-VMs were then created with custom software. There was no significant difference in mean bipolar voltage on EAMs and non-invasive 3D-VMs created for the test set (1.7±1.2 vs. 1.6±1.7 mV,P=0.17). Linear regression analysis revealed a significant association between bipolar voltages on invasive EAM and noninvasive 3D-VMs (P<0.001, R=0.79).
Conclusions: The independent associations of local bipolar voltage with LVWT, ST on LGE-CMR enable the creation of accurate non-invasive 3D-VMs based on LGE-CMR. This novel methodology may improve the safety and efficacy of catheter ablation in patients with ischemic scar-related VT.
- © 2011 by American Heart Association, Inc.