Cardiac Arrhythmia Modeling Minisymposium
February 17, 2021
By Cathy Diep
The Institute of Engineering in Medicine hosted a virtual Minisymposium on “Cardiac Arrhythmia Modeling”, featuring speakers Dr. Nele Vandersickel of Ghent University and Dr. Gordon Ho of UC San Diego. The Minisymposium was attended by 28 participants from 5 countries, and prompted plans for new clinical and basic sciences collaborations between UC San Diego and Ghent University.
Dr. Gordon Ho, a clinical electrophysiologist, assistant clinical professor, and researcher at UC San Diego and the Veterans Affairs San Diego Medical Center, spoke about “Clinical mapping approaches for cardiac fibrillation”. Dr. Ho explained that there are unmet clinical needs in diagnosing and treating arrhythmias, and there is a need to translate engineering techniques to improve arrhythmia treatment. Standard clinical mapping approaches such as activation mapping and substrate mapping may be used to localize stable, organized, and reentrant arrhythmias, but these approaches have pitfalls.
Standard clinical mapping approaches for cardiac arrythmias - activation mapping (left) and substrate mapping (right)
Invasive mapping is time-consuming, taking several hours to complete. Mapping of fibrillation is limited, since activation mapping methods using standard catheters can’t adequately localize drivers of fibrillation. There is a need for better non-invasive mapping strategies, which may be met by computer modeling. Dr. Ho highlights electrocardiography (ECG) as an inexpensive tool that clinicians are familiar with, and believes that using ECG in combination with computer modeling is a promising tool to help better understand and potentially help guide therapy of atrial fibrillation.
Dr. Nele Vandersickel discussed her research on “Network theory as a novel tool to detect different types of reentry in cardiac arrhythmia”. While network theory is broadly applied as the basis of the Google Search algorithm, to describe Facebook networking, and in brain research, network theory had not previously been used to analyze cardiac arrhythmias. Using network theory, Dr. Vandersickel’s research group has developed a novel method called directed-graph mapping (DG-mapping or DGM), which converts cardiac electrical mapping measurements in atrial and ventricular tachyarrhythmias into networks. By analyzing this network, it is possible to identify primary and secondary circuits of reentrant activation. It takes approximately 20 seconds for DGM to produce and automatically analyze a map of the heart to find the type and localize the source of an arrhythmia.
DG-mapping of clinical atrial tachycardia arrhythmia (above), DG-mapping automated reentry results (below)
Dr. Vandersickel has clinically tested her DG-mapping method on atrial tachycardia arrhythmias, and has found that DGM has a 74% success rate, greater than the 64% rate of the currently used HDAM cardiac imaging method. She is currently testing a new method, which has the possibility to increase this number to 90%. In the future, Dr. Nele Vandersickel and her research team want to test DGM in more cardiac arrhythmia cases. Their goals include applying DGM to atrial fibrillation, investigating ventricular tachycardia arrhythmias, and making DGM work perfectly on atrial tachycardia arrhythmias. Dr. Vandersickel and her team plan on launching a website to make DGM available for non-commercial use in April 2020.
During this symposium, Dr. Vandersickel, Dr. Ho, and other researchers in attendance made plans for new research collaborations between UC San Diego and Ghent University. For more information on their research, please contact Dr. Vandersickel at nele.vandersickel@ugent.be, Dr. Ho at goho@ucsd.edu, or the Institute of Engineering in Medicine (IEM) at iem@ucsd.edu.
