Spread of excitation in a myocardial volume: simulation studies in a model of anisotropic ventricular muscle activated by point stimulation.

摘要: Spread of Excitation in a Myocardial Volume. Introduction: The purpose this study was to present simulations excitation wavefronts spreading through parallelepipedal slab ventricular tissue measuring 6.5 × 1.0cm. Methods and Results: incorporates the anisotropic properties myocardium including transmural counterclockwise fiber rotation from epicardium endocardium. Simulations were based on an eikonal model that determines times throughout wall, which is represented as bidomain. initiated by delivering ectopic stimuli at various intramural depths. We also investigated effect simplified Purkinje network patterns. plane pacing, parallel epicardial-endocardial surfaces, oblong with major axis approximately oriented along local direction, bulges deformations due attraction rotating fibers adjacent planes. intersections wavefront planes increasing distance pacing rotated clockwise or counterclockwise, depending depth, but always less than same plane. For all depths, returned toward pacing. Return occurred multiple, varying sectors observed close 6 mm site. Conclusion: Curvature collision boundaries markedly affected velocities. Shape separation epicardial isochrones spatial distribution velocities varied function site depth When added model, revealed subendocardial location Purkinje-myocardial junctions. Considerable insight into events could be obtained isochrones. If validated experimentally, results may applicable recorded surgery.