A comprehensive framework for evaluation of high pacing frequency and arrhythmic optical mapping signals

Area of Science:

• Cardiac Electrophysiology
• Biomedical Imaging
• Computational Biology

Background:

• High pacing frequencies and arrhythmias create complex optical mapping signals, challenging traditional analysis methods.
• Accurate processing of these signals is crucial for understanding cardiac electrical behavior and developing therapeutic strategies.

Purpose of the Study:

• To develop an automated, activation time-based analytical framework for optical mapping images.
• To accurately process complex cardiac electrical activity, including arrhythmias and reentrant patterns.

Main Methods:

• Utilized Hilbert transform phase for deriving activation time windows centered on action potential upstrokes.
• Evaluated upstroke morphology and signal derivatives to define activation times.
• Grouped spatio-temporal activation points into wave fronts for classification and analysis of origin sites and repolarization.

Main Results:

• The framework successfully mapped activation times during complex events like rotor-like reentry and ventricular fibrillation.
• Phase windowing accurately recapitulated repetitive behaviors and revealed spatially coherent activation patterns.
• Identified conduction slowing and dynamic repolarization changes, pinpointing focal origins and breakthrough sites.

Conclusions:

• The developed analytical framework provides a comprehensive approach for quantitative assessment and visualization of complex cardiac electrical activity.
• Enables detailed analysis of wave front dynamics, conduction properties, and repolarization during arrhythmias.