Virtual EP study in 3-D CMR imaging model

Virtual EP study in 3-D CMR imaging model

Jason Ng and colleagues have found good correlation between invasive electrophysiological (EP) study and virtual EP study in a three dimensional (3-D) cardiac magnetic resonance (CMR) imaging model of myocardial infarction in pigs [Virtual Electrophysiological Study in a 3-Dimensional Cardiac Magnetic Resonance Imaging Model of Porcine Myocardial Infarction. J Am Coll Cardiol. 2012;60:423-30]. After inducing myocardial infarction in pigs, 3-dimensional cardiac magnetic resonance imaging was done after the recovery period. The voxel intensity was used to classify into normal areas, gray zones and infarct cores. Slower conduction and longer action potentials were assigned to gray zones in the computer model. Virtual EP study was performed in the computer model and real EP study was performed in vivo with programmed stimulation and noncontact mapping. Seven of the eight pigs had inducible VT (ventricular tachycardia) on real EP study, of which six had it during virtual EP study. Four of these had simulated VT reentrant circuits quite similar to that obtained with noncontact mapping. The other two had similar circuits, but propagation was in opposite directions. Authors state that mathematical models applied to 3-dimensional cardiac magnetic resonance images could be useful in planning catheter ablation and in identifying those at risk for VT episodes.