UF Mathematics Colloquium Abstract:
Pengcheng Shi
Rochester Institute of Technology
Volumetric Imaging of Cardiac Electrophysiology: A Model-Based Paradigm
4:05 p.m. Monday, November 23, 2009
339 Little Hall (Atrium)
Personalized noninvasive imaging of subject-specific cardiac electrical
activity can guide and improve preventive diagnosis and treatment of cardiac
arrhythmia. Compared to body surface potential (BSP) recordings and
electrophysiological information reconstructed on heart surfaces, volumetric
myocardial transmembrane potential (TMP) dynamics is of greater clinical
importance in exhibiting arrhythmic details and arrythmogenic substrates
inside the myocardium. We present a physiological-model-constrained
statistical framework that uses noninvasive BSP measurements and tomographic
images of individual subjects to reconstruct subject-specific volumetric TMP
dynamics and/or tissue excitability inside the 3D myocardium. General
knowledge of volumetric TMP activity is incorporated through cardiac
electrophysiological models so as to constrain TMP reconstruction. A maximum
a posteriori estimation framework is then developed to use stochastic state
space system and nonlinear data assimilation to estimate volumetric
myocardial TMP dynamics and/or tissue excitability from personal BSP data.
Robustness of the presented framework to practical model and data errors is
evaluated. Computational phantom experiments on a variety of cardiac
pathologies demonstrate the potential of this framework in identifying local
arrhythmic details inside the myocardium; particularly, comparison with
classical regularization-based approaches shows that this framework is able
to improve the accuracy of epicardial potential reconstruction. Real-data
experiments on post myocardial infarction patients further present the
unique ability of this framework in providing noninvasive imaging of
volumetric cardiac electrical dynamics and tissue property for individual
subjects, as well as the advantage in noninvasive imaging and quantitation
of myocardial infarction.