Methodology for Cross-Talk Elimination in Simultaneous Voltage and Calcium Optical Mapping Measurements With Semasbestic Wavelengths

• Type of Material: Article
• Authors: Ilija Uzelac, Georgia Institute of Technology; Christopher J Crowley, Georgia Institute of Technology; Shahriar Iravanian, Emory University; Tae Yun Kim, Emory University; Hee Cho, Emory University; Flavio H Fenton, Georgia Institute of Technology
• Language: English
• Date: 2022-02-11
• Publisher: FRONTIERS MEDIA SA
• Publication Version: Final Published Version
• Copyright Statement: © 2022 Uzelac, Crowley, Iravanian, Kim, Cho and Fenton.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.3389/fphys.2022.812968
• Title of Journal or Parent Work: FRONTIERS IN PHYSIOLOGY
• Volume: 13
• Start Page: 812968
• End Page: 812968
• Grant/Funding Information: This study was supported by grants NIH 1R01HL143450-01, National Science Foundation 1446675, American Heart Association 15POST25700285, NHLBI R01HL143065, NHLBI R01HL147270, NHLBI R01HL157363, 20TPA35260085, and Department of Defense GRANT12901705 (PR191598).
• Keywords: semasbestic wavelength; alternans; Science & Technology; isosbestic point; optical mapping; MECHANISM; ACTION-POTENTIALS; Life Sciences & Biomedicine; transmembrane voltage; fluorescent dyes; intracellular free calcium concentration; TRANSIENTS; T-WAVE ALTERNANS; FIBRILLATION; INSTABILITY; DEATH; EXCITATION; Physiology; HEART-FAILURE; PHYSIOLOGY
• Research Categories: Engineering, Biomedical

Abstract

Most cardiac arrhythmias at the whole heart level result from alteration of cell membrane ionic channels and intracellular calcium concentration ([Ca2+]i) cycling with emerging spatiotemporal behavior through tissue-level coupling. For example, dynamically induced spatial dispersion of action potential duration, QT prolongation, and alternans are clinical markers for arrhythmia susceptibility in regular and heart-failure patients that originate due to changes of the transmembrane voltage (Vm) and [Ca2+]i. We present an optical-mapping methodology that permits simultaneous measurements of the Vm - [Ca2+]i signals using a single-camera without cross-talk, allowing quantitative characterization of favorable/adverse cell and tissue dynamical effects occurring from remodeling and/or drugs in heart failure. We demonstrate theoretically and experimentally in six different species the existence of a family of excitation wavelengths, we termed semasbestic, that give no change in signal for one dye, and thus can be used to record signals from another dye, guaranteeing zero cross-talk.