Abstract:
:Mathematical modeling of the cardiac action potential has proven to be a powerful tool for illuminating various aspects of cardiac function, including cardiac arrhythmias. However, no currently available detailed action potential model accurately reproduces the dynamics of the cardiac action potential and intracellular calcium (Ca(i)) cycling at rapid heart rates relevant to ventricular tachycardia and fibrillation. The aim of this study was to develop such a model. Using an existing rabbit ventricular action potential model, we modified the L-type calcium (Ca) current (I(Ca,L)) and Ca(i) cycling formulations based on new experimental patch-clamp data obtained in isolated rabbit ventricular myocytes, using the perforated patch configuration at 35-37 degrees C. Incorporating a minimal seven-state Markovian model of I(Ca,L) that reproduced Ca- and voltage-dependent kinetics in combination with our previously published dynamic Ca(i) cycling model, the new model replicates experimentally observed action potential duration and Ca(i) transient alternans at rapid heart rates, and accurately reproduces experimental action potential duration restitution curves obtained by either dynamic or S1S2 pacing.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Mahajan A,Shiferaw Y,Sato D,Baher A,Olcese R,Xie LH,Yang MJ,Chen PS,Restrepo JG,Karma A,Garfinkel A,Qu Z,Weiss JNdoi
10.1529/biophysj.106.98160subject
Has Abstractpub_date
2008-01-15 00:00:00pages
392-410issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(08)70718-5journal_volume
94pub_type
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