A computer model of the electrogram: what causes fractionation?
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Updated: Aug 17, 2026

The Optical Fractionator Technique to Estimate Cell Numbers in a Rat Model of Electroconvulsive Therapy
Published on: July 9, 2017
M D Lesh1, J F Spear, M B Simson
1Cardiovascular Section, Hospital of the University of Pennsylvania, Philadelphia 19104.
Abstract:
Fractionated electrograms are frequently recorded during mapping studies in patients with coronary artery disease and ventricular tachycardia. The authors developed a computer model of electrogram generation based on the biophysics of volume conductor fields. They show that fractionated electrograms can be produced as otherwise uniform wavefronts of activation encounter regions of increased cellular coupling resistance. Because of this, local activation may not correspond to the largest or most rapid deflection in a polyphasic, fractionated electrogram.
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