Alena Talkachova (Elena Tolkacheva)Professor, Department of Biomedical Engineering
BS, Physics, Belarussian State University, Minsk, Belarus, 1991
MS, Physics, Belarussian State University, Minsk, Belarus, 1992
PhD, Nonlinear optics and laser physics, Nice University, Nice France, 2003
The mechanical contractions of the heart are triggered by electrical waves of excitation propagating through cardiac tissue. Abnormalities in the wave propagation, including fast and chaotic propagation in the heart, may lead to fatal cardiac arrhythmias, such as ventricular fibrillation (VF) and atrial fibrillation (AF).
The general goal of Dr. Talkachova’s group is to investigate the electrical activity of the whole heart from a nonlinear dynamics perspective, aiming to reveal mechanisms of complex cardiac rhythms leading to VF and AF.
We use high resolution optical mapping technique to record electrical activity from the ex-vivo hearts, as well as small patches of stem cells, with the help of voltage- and calcium-sensitive dyes. Analysis of complex spatio-temporal dynamics of the electrical and mechanical activity in the heart helps us to develop techniques for prediction and control of cardiac arrhythmias.
In one of our projects, we develop anti-arrhythmic pacing protocols that can improve the pacing modality of the heart and prevent it from going into VF. In another project, we are developing new signal processing techniques to identify the sources of electrical turbulence during AF. These techniques are to be used for guiding clinicians who perform mapping-specific AF ablation in patients.
Finally, we are interested in investigating the therapeutic potential of neuromodulation, specifically, vagal nerve stimulation, for treatment of cardiovascular diseases and hypertension.
S. Mironov, J. Jalife, E.G. Tolkacheva. "The role of conduction velocity restitution and short term memory in the development of APD alternans in isolated rabbit hearts", Circulation, 118:17-25, 2008. (abstract)
E.G. Tolkacheva "The rate- and species-dependence of short-term memory in cardiac myocytes" J. Biol. Physics, 33:35-37, 2007.
M. Cerrone, S.F. Noujaim, E.G. Tolkacheva, A.Talkachou, O. Berenfeld, J. Anumonwo, S. Pandit, K. Vikstrom, C. Napolitano, S.G. Priori and J. Jalife, Arrtythmogenic mechanisms in a mouse model of catecholaminergic polymorphic ventricular tachycardia, Circ. Res. 9:1039-1048, 2007. (abstract)
D.G. Schaeffer, J.W. Cain, D.J. Gauthier, S.S. Kalb, R.A. Oliver, E.G. Tolkacheva, W. Ying, W. Krassowska, "An ionically based mapping model with memory for cardiac restitution" Bull Math Bio, 69:459-82, 2007. (abstract)
E.G. Tolkacheva, J.M.B. Anumonwo, J.J. Jalife "Action potential duration restitution portraits of mammalian ventricular myocytes: role of calcium current", Biophys J. 91(7):2735, 2006. (abstract)
V. Muñoz, R. Vaidyanathan, E.G. Tolkacheva, A. Dhamoon, S. Taffet, J.M.B. Anumonwo "Kir2.3 Isoform Confers pH Sensitivity to Kir2.1-Kir2.3 Heteromeric Channels, Heart Rhythm, 4:487-496, 2007. (abstract)
S.S. Kalb, E.G. Tolkacheva, D.G. Schaeffer, D.J. Gauthier, W. Krassowska "Restitution in mapping models with an arbitrary amount of memory", Chaos v. 15, p. 023701, 2005. (abstract)
J.W. Cain, E.G. Tolkacheva, D.G. Schaeffer, D.J. Gauthier "Rate-dependent waveback velocity of cardiac action potentials in a one-dimensional cable", Phys. Rev. E. v.70, p.061906, 2004. (abstract)
E.G. Tolkacheva, M.M. Romeo, M. Guerraty, D.J. Gauthier "Condition for alternans and its control in two-dimensional mapping model of paced cardiac tissue", Phys. Rev. E. v.69, p. 031904, 2004. (abstract)
S.S. Kalb, H. Dobrovolny, E.G. Tolkacheva, S.F. Idriss, W. Krassowska, D.J. Gauthier "The restitution portrait: a new method for investigating rate-dependence restitution", J. Cardiovasc. Electrophysiol., v.15, N6, p.698, 2004. (abstract)
E.G. Tolkacheva, M.M. Romeo, and D.J. Gauthier "Control of cardiac alternans in a mapping model with memory", Physica D, v.194, p.385, 2004.
E.G. Tolkacheva, D.G. Schaeffer, D.J. Gauthier, and W. Krassowska, "Condition for alternans and stability of the 1:1 response pattern in a memory model of paced cardiac dynamics", Phys. Rev. E. v.67, p.031904, 2003. (abstract)