Computationally Efficient Noninvasive Cardiac Activation Time Imaging

G. Fischer; B. Pfeifer; M. Seger; C. Hintermüller; F. Hanser; R. Modre; B. Tilg; T. Trieb; C. Kremser; F. X. Roithinger; F. Hintringer

doi:10.1055/s-0038-1634024

Methods of Information in Medicine, Table of Contents

Methods Inf Med 2005; 44(05): 674-686
DOI: 10.1055/s-0038-1634024

Original Article

Schattauer GmbH

Computationally Efficient Noninvasive Cardiac Activation Time Imaging

G. Fischer

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

B. Pfeifer

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

M. Seger

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

C. Hintermüller

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

F. Hanser

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

R. Modre

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

B. Tilg

¹Institute for Biomedical Signal Processing and Imaging, University for Health Sciences, Medical Informatics and Technology (UMIT), Innsbruck, Austria

,

T. Trieb

²Department of Radiology I, University Hospital Innsbruck, Innsbruck, Austria

,

C. Kremser

²Department of Radiology I, University Hospital Innsbruck, Innsbruck, Austria

,

F. X. Roithinger

³Department of Cardiology, University Hospital Innsbruck, Innsbruck, Austria

,

F. Hintringer

³Department of Cardiology, University Hospital Innsbruck, Innsbruck, Austria

› Author Affiliations

Abstract

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Summary

Objective: The computer model-based computation of the cardiac activation sequence in humans has been recently subject of successful clinical validation. This method is of potential interest for guiding ablation therapy of arrhythmogenic substrates. However, computation times of almost an hour are unattractive in a clinical setting. Thus, the objective is the development of a method which performs the computation in a few minutes run time.

Methods: The computationally most expensive part is the product of the lead field matrix with a matrix containing the source pattern on the cardiac surface. The particular biophysical properties of both matrices are used for speeding up this operation by more than an order of magnitude. A conjugate gradient optimizer was developed using C++ for computing the activation map.

Results: The software was tested on synthetic and clinical data. The increase in speed with respect to the previously used Fortran 77 implementation was a factor of 30 at a comparable quality of the results. As an additional finding the coupled regularization strategy, originally introduced for saving computation time, also reduced the sensitivity of the method to the choice of the regularization parameter.

Conclusions: As it was shown for data from a WPW-patient the developed software can deliver diagnostically valuable information at a much shorter span of time than current clinical routine methods. Its main application could be the localization of focal arrhythmogenic substrates.

Keywords

Cardiac electrophysiology - computer modeling - inverse problem

PDF (981 kb)

References

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