Role of temperature on nonlinear cardiac dynamics

Area of Science:

• Cardiac Electrophysiology
• Biophysics
• Computational Biology

Background:

• Cardiac tissue spatiotemporal behavior is sensitive to thermal fluctuations.
• Understanding temperature's role in proarrhythmic dynamics is crucial for cardiac health.

Purpose of the Study:

• To investigate the influence of temperature variations on cardiac tissue dynamics.
• To model and experimentally validate the relationship between temperature and proarrhythmic properties.

Main Methods:

• A minimal cardiac tissue model with thermoelectric coupling was developed.
• Experimental data from canine ventricles at varying temperatures were used for validation.
• Quantitative analysis of restitution, conduction velocity, and alternans regimes was performed.

Main Results:

• The model successfully reproduced experimentally observed cardiac dynamics across different temperatures.
• Temperature-dependent proarrhythmic properties, including complex discordant alternans, were quantitatively described.
• Simulations and experiments revealed specific alternans patterns (one wave front, three wave backs) enhancing tissue dispersion.

Conclusions:

• Thermoelectric coupling provides a viable approach to study temperature effects on cardiac tissue.
• Temperature is a critical factor modulating cardiac electrical stability and proarrhythmic risk.
• Findings have implications for generalizing cardiac models and understanding thermal influences on heart function.