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Updated: Aug 7, 2026
Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations
Published on: January 8, 2013
A spatial scale factor for electrophysiological models of myocardium
1University of Arizona, Tucson 85721, USA. art@cochise.biosci.arizona.edu
Insights
Sudden cardiac death, often without warning, involves the heart entering fibrillation. This study narrows the estimated range for
Area of Science:
- Biophysics
- Cardiology
- Computational Biology
Background:
- Sudden cardiac death (SCD) accounts for a significant portion of male deaths (20-64 years) in the US.
- A quarter of SCD cases lack forewarning or visible autopsy cause, often due to cardiac fibrillation.
- Cardiac fibrillation is characterized as electrical turbulence, distinct from normal heart rhythm.
Purpose of the Study:
- To refine the estimated range for the biophysical parameter 'D', crucial for understanding cardiac fibrillation.
- To provide a more accurate basis for studying the spatio-temporal dynamics of fibrillation and defibrillation.
Main Methods:
- Analysis of diverse recent experimental data.
- Biophysical modeling focusing on the role of the spatial parameter 'D'.
Main Results:
- Experimental evidence supports a narrower range of realistic values for the biophysical parameter 'D'.
- The parameter 'D' significantly influences the spatial pattern and evolution of cardiac fibrillation.
Conclusions:
- A refined understanding of 'D' is essential for comprehending cardiac fibrillation mechanisms.
- Accurate 'D' values are critical for developing effective defibrillation strategies and preventing sudden cardiac death.
Abstract:
In the United States among males 20-64 years old about 1/3 of deaths are classified as 'sudden cardiac death', and 1/4 had no forewarning, nor did autopsy turn up any visible cause. The heart just switches from its normally periodic pumping to an alternative mode called 'fibrillation' more resembling electrical turbulence. In normal tissue its mechanism is a geometrically re-entrant mode of normal propagation. Everything about this spatial pattern depends upon the magnitude of 'D', the one term with dimension involving space in the pertinent biophysical equations. Explicit or implicit estimates in current literature span orders of magnitude. In this article I argue from a diversity of recent experiments for a narrower range of realistic values. It has an important role in the spatio-temporal evolution of fibrillation and in defibrillation.
