Propagation Velocity in Cardiac Muscle Bundles
Author Information
Author(s): Nicholas Sperelakis, Lakshminarayanan Ramasamy
Primary Institution: University of Cincinnati
Hypothesis
The effect of depth on propagation velocity within a bundle of cardiac muscle fibers is likely to be an important factor in the genesis of some heart arrhythmias.
Conclusion
When there were no or few gj-channels, the profile was bell-shaped with the core velocity less than half that at the surface, while many gj-channels resulted in a flat profile.
Supporting Evidence
- The velocity profile was bell-shaped when there were 0 or only 1 gj-channel.
- With 100 gj-channels, the velocity profile was flat.
- The surface/core ratio of velocities was dependent on the values of Rol2 and RBT.
- When Rol2 was lowered 10-fold, the surface velocity increased slightly.
- Varying Rol2 and RBT had almost no effect on the velocity profile.
Takeaway
This study looked at how fast signals travel in heart muscle and found that signals travel slower in the middle than on the outside, especially when there are fewer connections between the cells.
Methodology
The study used a PSpice model to simulate action potentials in a cardiac muscle bundle, examining the velocity profile based on the number of gap-junction channels and resistance values.
Digital Object Identifier (DOI)
Want to read the original?
Access the complete publication on the publisher's website