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The strength-interval curve in cardiac tissue
Sunil M Kandel1, Bradley J Roth
1Department of Physics, Oakland University, Rochester, MI 48309, USA.
Abstract:
The bidomain model describes the electrical properties of cardiac tissue and is often used to simulate the response of the heart to an electric shock. The strength-interval curve summarizes how refractory tissue is excited. This paper analyzes calculations of the strength-interval curve when a stimulus is applied through a unipolar electrode. In particular, the bidomain model is used to clarify why the cathodal and anodal strength-interval curves are different, and what the mechanism of the "dip" in the anodal strength-interval curve is.
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