Abstract:
:Voltage-sensitive fluorescent dyes are commonly used to measure cardiac electrical activity. Recent studies indicate, however, that optical action potentials (OAPs) recorded from the myocardial surface originate from a widely distributed volume beneath the surface and may contain useful information regarding intramural activation. The first step toward obtaining this information is to predict OAPs from known patterns of three-dimensional (3-D) electrical activity. To achieve this goal, we developed a two-stage model in which the output of a 3-D ionic model of electrical excitation serves as the input to an optical model of light scattering and absorption inside heart tissue. The two-stage model permits unique optical signatures to be obtained for given 3-D patterns of electrical activity for direct comparison with experimental data, thus yielding information about intramural electrical activity. To illustrate applications of the model, we simulated surface fluorescence signals produced by 3-D electrical activity during epicardial and endocardial pacing. We discovered that OAP upstroke morphology was highly sensitive to the transmural component of wave front velocity and could be used to predict wave front orientation with respect to the surface. These findings demonstrate the potential of the model for obtaining useful 3-D information about intramural propagation.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Hyatt CJ,Mironov SF,Wellner M,Berenfeld O,Popp AK,Weitz DA,Jalife J,Pertsov AMdoi
10.1016/S0006-3495(03)74690-6subject
Has Abstractpub_date
2003-10-01 00:00:00pages
2673-83issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(03)74690-6journal_volume
85pub_type
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