Related Experiment Video
Updated: Feb 8, 2026

Optical Mapping of Action Potentials and Calcium Transients in the Mouse Heart
Published on: September 13, 2011
The Visible Heart® project and methodologies: novel use for studying cardiac monophasic action potentials and
Megan M Schmidt1, Paul A Iaizzo2
1a Department of Biomedical Engineering , University of Minnesota , Minneapolis , MN , USA.
Introduction:
This review describes the utilization of Visible Heart® methodologies for electrophysiologic studies, specifically in the investigation of monophasic action potential (MAP) recordings, with the aim to facilitate new catheter/device design and development that may lead to earlier diagnosis, treatment, and ultimately a higher quality of life for patients with atrial fibrillation.
Areas Covered:
We describe the historically proposed mechanisms behind which electrode is responsible for the MAP recording, new catheters for recording these signals, and how Visible Heart methodologies can be utilized to develop and test new technologies for electrophysiologic investigations.
Expert Opinion:
When compared to traditional electrogram recordings, MAP waveforms provide clinical information vital to the understanding, diagnosis, and treatment of cardiac arrhythmias. New catheters and ablation technologies are routinely being assessed on reanimated large mammalian hearts (swine and human) in our laboratory. These abilities, combined with continued enhancements in imaging modalities and computational systems for electrical mapping, are being applied to the MAP catheter design process. Through this testing we are hopeful that the time from concept to product can be reduced, and that an array of MAP catheters can be placed in the hands of physicians, where they will improve patient outcomes.
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