Skeletal muscle grids for assessing current distributions from defibrillation shocks.
This paper utilizes a structured and an unstructured grid representation of a torso with an anisotropic skeletal muscle to assess current distributions from defibrillation shocks. The results show that a finite-element solution on an unstructured grid of 400,000 elements (60,000 nodes) achieves comparable current distributions with a finite-difference solution on a structured grid that uses approximately the same number of nodes. Moreover, a finite-element solution on a 65,000-element (10,500 nodes) unstructured grid yielded fractional percent current results within 5% of the finer grids. The structured and unstructured grid models are used to investigate recent interpretations of experimental data that concluded that more than 80% of the total defibrillation current is shunted by the anisotropic skeletal muscle thoracic cage. It is concluded that these interpretations, which were based on a one-dimensional resistive network representation of the three-dimensional defibrillation situation, overestimate by 25% the current shunted by the anisotropic thoracic cage.
Schmidt
J
J
National Science Foundation/Engineering Research Center, Department of Electrical Engineering, Duke University, Durham, North Carolina.
Gatlin
B
B
Eason
J
J
Koomullil
G
G
Pilkington
T
T
D000818:Animals; D004285:Dogs; D004554:Electric Countershock; D008954:Models, Biological; D009132:Muscles / Q000502:physiology*; D013499:Surface Properties; D013909:Thorax