Related Experiment Video
Updated: Dec 31, 2025
Dual-Dye Optical Mapping of Hearts from RyR2R2474S Knock-In Mice of Catecholaminergic Polymorphic Ventricular Tachycardia
Published on: December 22, 2023
Temporal irregularity quantification and mapping of optical action potentials using wave morphology similarity
Christopher O'Shea1, James Winter2, Andrew P Holmes3
1Institute of Cardiovascular Sciences, University of Birmingham, UK; EPSRC Centre for Doctoral Training in Physical Sciences for Health, School of Chemistry, University of Birmingham, UK; School of Computer Science, University of Birmingham, Birmingham, B15 2TT, UK.
We developed a new method, optical wave similarity (OWS), to analyze cardiac action potential (AP) waveforms. OWS mapping effectively detects and quantifies temporal instability in optical mapping data, aiding arrhythmia research.
Area of Science:
- Cardiovascular Physiology
- Biomedical Engineering
- Computational Biology
Background:
- Cardiac optical mapping offers high-resolution visualization of action potential (AP) morphology.
- Temporal changes in AP morphology are linked to arrhythmia development and progression.
- Current methods for analyzing AP morphology can be restrictive and user-dependent.
Purpose of the Study:
- To develop and validate a semi-automated, user-unbiased method for detecting and quantifying temporal instability in cardiac optical mapping datasets.
- To assess the utility of quantifying waveform regularity for arrhythmia detection.
Main Methods:
- Developed and applied optical wave similarity (OWS) algorithms to analyze the complete morphology of optically recorded AP waveforms.
- OWS quantification avoids restrictive definitions of specific signal points, focusing on overall waveform similarity.
- Validated OWS using model datasets and tested its application in ex vivo guinea pig hearts and mouse atria.
Main Results:
- OWS successfully detected and quantified alterations in AP morphology temporal regularity.
- The method demonstrated sensitivity to various proarrhythmic stimuli, including changes in pacing frequency, premature contractions, alternans, and ventricular fibrillation.
- OWS mapping proved effective in identifying and measuring temporal instability in optical mapping data.
Conclusions:
- OWS mapping is an effective tool for measuring temporal regularity in optical mapping datasets.
- This methodology offers a novel metric for assessing arrhythmia inducibility and scoring.
- OWS provides a user-unbiased approach to analyzing action potential morphology in cardiac optical mapping.
