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Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
A discrete-time control algorithm applied to closed-loop pacing of HL-1 cardiomyocytes
R Hollis Whittington1, Gregory T A Kovacs
1Department of Electrical Engineering, Stanford University, Stanford, CA 94305-4075, USA. hollis.whittington@biotronik.com
IEEE Transactions on Bio-Medical Engineering
|February 1, 2008
Summary
This study introduces a new algorithm for closed-loop electrical stimulation of cardiomyocytes. The temporal error-controlled algorithm (TECA) accurately measures stimulation thresholds in real-time, advancing cardiac research.
Area of Science:
- Biomedical Engineering
- Cellular Electrophysiology
Background:
- Electrical stimulation is crucial for studying excitable cells like cardiomyocytes.
- Accurate measurement of stimulation thresholds and transient effects has been challenging with existing methods.
Purpose of the Study:
- To develop a novel closed-loop electrical stimulation controller for cardiomyocytes.
- To introduce and validate the temporal error-controlled algorithm (TECA) for precise stimulation parameter measurement.
Main Methods:
- Utilized a discrete-time algorithmic controller for closed-loop stimulation of HL-1 cardiomyocytes on a microelectrode array.
- Employed the temporal error-controlled algorithm (TECA) with capture fraction as a feedback parameter.
- Developed a partial capture model for algorithm analysis and compared performance with a conditional convergence algorithm via simulation.
Main Results:
- The TECA algorithm demonstrated effective closed-loop control and accurate measurement of stimulation thresholds.
- Real-time tracking of stimulation threshold changes in response to potassium concentration shifts was successfully demonstrated.
- The algorithm enables continuous monitoring of stimulation threshold as a dynamic parameter.
Conclusions:
- The temporal error-controlled algorithm (TECA) offers a significant advancement for electrophysiologic investigation of cardiomyocytes.
- This method allows for real-time monitoring of stimulation threshold, with broad applications in cardiac pharmacology, electrophysiology, and biosensing.
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