Abstract:
:Heart surface optical mapping of transmembrane potentials has been widely used in studies of normal and pathological heart rhythms and defibrillation. In these studies, three-dimensional spatio-temporal events can only be inferred from two-dimensional surface potential maps. We present a novel optical system that enables high fidelity transmural recording of transmembrane potentials. A probe constructed from optical fibers is used to deliver excitation light and collect fluorescence from seven positions, each 1 mm apart, through the left ventricle wall of the rabbit heart. Excitation is provided by the 488-nm line of a water-cooled argon-ion laser. The fluorescence of the voltage-sensitive dye di-4-ANEPPS from each tissue site is split at 600 nm and imaged onto separate photodiodes for later signal ratioing. The optics and electronics are easily expandable to accommodate multiple optical probes. The system is used to record the first simultaneous measurements of transmembrane potential at a number of sites through the intact heart wall.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Hooks DA,LeGrice IJ,Harvey JD,Smaill BHdoi
10.1016/S0006-3495(01)75910-3subject
Has Abstractpub_date
2001-11-01 00:00:00pages
2671-80issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(01)75910-3journal_volume
81pub_type
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