Abstract
Rotating nonlinear waves of excitation in the heart cause dangerous cardiac arrhythmias. Frequently, ventricular arrhythmias occur as a result of myocardial infarction and are associated with rotation of the waves around a post-infarction scar. In this paper, we perform a detailed in silico analysis of scroll waves in an anatomical model of the human ventricles with a generic model of the infarction scar surrounded by the gray zone with modified properties of the myocardial tissue. Our model includes a realistic description of the heart shape, anisotropy of cardiac tissue and a detailed description of the electrical activity in human ventricular cells by a TP06 ionic model. We vary the size of the scar and gray zone and analyze the dependence of the rotation period on the injury dimensions. Two main regimes of wave scrolling are observed: the scar rotation, when the wave rotates around the scar, and the gray zone rotation, when the wave rotates around the boundary of the gray zone and normal tissue. The transition from the gray zone to the scar rotation occurs for the width of gray zone above 10–20 mm, depending on the perimeter of the scar. We compare our results with simulations in 2D and show that 3D anisotropy reduces the period of rotation. We finally use a model with a realistic shape of the scar and show that our approach predicts correctly the period of the arrhythmia.
Highlights
Rotational activity of excitation waves in the heart is the most important mechanism of the dangerous cardiac arrhythmias
We studied ventricular excitation patterns for scroll waves rotating around a postinfarction scar
In most of the cases, we observed stationary rotation with a constant period. We studied how this period depends on the perimeter of the compact infarction scar (Piz) and the width of the gray zone
Summary
Rotational activity of excitation waves in the heart is the most important mechanism of the dangerous cardiac arrhythmias. Anatomical reentry in most of the cases was considered in generic 2D formulations [1,2,3,4,5,6] These studies revealed important characteristics of the waves, such as non-monotonic dependency of the period of rotation on obstacle size [1], dynamical instabilities [6], anchoring [2], and transitions from anatomical to functional reentry [1,3]. Application of these results in cardiology is not straightforward. In that case such obstacles contain a compact scar which is fully inexcitable region, surrounded by so called gray zone—a region where properties of cardiac tissue are different from the properties of the normal myocardium [9]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
