Noninvasive ECG Imaging (ECGI) of Cardiac Arrhythmias

An increasing body of evidence links variability in response to drug therapy to common DNA polymorphisms. In some cases, such DNA variants occur in genes known to be responsible for drug action. Examples in cardiovascular therapy include will describe the application in humans of a new imaging modality called Electrocardiographic Imaging (ECGI) that noninvasively images cardiac electrical activity on the heart epicardial surface. In ECGI, a multi-electrode vest (or strips) records 250 body-surface electrocardiograms; then, using geometrical information from a CT scan and an inverse solution to Laplace equation, electrical potentials, electrograms, activation sequences (isochrones) and repolarization patterns are reconstructed on the heart surface. I will show examples of imaged atrial and ventricular activation and ventricular repolarization in the normal heart and during cardiac arrhythmias. References: 1. C. Ramanathan, R.N. Ghanem, P. Jia, K. Ryu, Y. Rudy. Noninvasive Electrocardiographic Imaging for cardiac electrophysiology and arrhythmia. Nature Medicine 2004; 10: 422-428. 2. C. Ramanathan, P. Jia, R.N. Ghanem, K. Ryu, Y. Rudy. Activation and repolarization of the normal human heart under complete physiological conditions. Proc Nat Acad Sci USA (PNAS) 2006; 103: 6309-6314. 3. P.S. Cuculich, Y. Wang, B.D. Lindsay, M.N. Faddis, R.B. Schuessler, R.D. Damiano, L. Li, Y. Rudy. Noninvasive Characterization of Epicardial Activation in Humans with Diverse Atrial Fibrillation Patterns. Circulation 2010;122:1364-1372.