What can we learn from the optically recorded epicardial action potential?

Area of Science:

• Cardiovascular Physiology
• Biophysics
• Computational Biology

Background:

• Optical mapping with voltage-sensitive dyes is crucial for studying cardiac excitation propagation.
• Previous research suggests optical upstroke morphology indicates subsurface excitation front orientation.
• A computational study by Bishop et al. presented cases of differing propagation directions yielding similar epicardial optical upstrokes.

Discussion:

• This comment addresses the interpretation of optical upstroke morphologies.
• It aims to reconcile Bishop et al.'s findings with existing computational and experimental data.
• The focus is on understanding how subsurface excitation influences observable optical signals.

Key Insights:

• Optical upstroke morphology is not solely determined by propagation direction.
• Subsurface excitation front orientation significantly impacts optical signal interpretation.
• Reconciling different study results requires a nuanced understanding of optical mapping principles.

Outlook:

• Further computational and experimental validation is needed.
• Refined models can improve the interpretation of optical mapping data.
• This work contributes to a more accurate understanding of cardiac electrophysiology via optical techniques.