1. Alexander Kursanov
Institute of Immunology and Physiology of the UB RAS
Ural Federal University
Ekaterinburg, Russia
15/04/2014

2. EC coupling in cardiomyocytes
Rheological scheme of cardiomyocyte model «Ekaterinburg-Oxford». CE – contractile element (sarcomere); PE, SE -- parallel and series elastic elements; XSE – external series elastic element; VS – parallel viscous element
Bers D. Nature (2002)
Написать что такое N и A
Electrical block
Mechanical block
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3. Reduced Na+-K+ pump Gradual increase in [Na+]i Accumulation of
Na+-Ca2+
exchanger
Reduced
Na+-K+ pump
Gradual increase in [Na+]i
Accumulation of
Ca2+ in cytosol
Spontaneous Ca2+ release
to cytosol between stimuli
Spontaneous AP
contraction
Accumulation
of Ca2+ in SR
Ca2+ overload of
SR terminal cisterns
N (normal NKP)
SC (sub-critical NKP inhibition and Ca2+ SR overload)
P (pathological NKP inhibition and Ca2+ SR overload)
Km,Na<37 mM
Km,Na<153%*
37 mM≤Km,Na<40 mM
153%*≤Km,Na<165%*
Km,Na≥40 mM
Km,Na≥165%*
Sulman et al., Bull Math Biol, 2008
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4. Experimental validation of cellular modeling predictions
According to the model predictions the following mechanical factors appear to facilitate arrhythmia emergence:
a decrease in the mechanical load in afterloaded contractions;
a decrease in the initial length of sarcomeres in isometric twitches.
mechanical interactions between myocardial segments with different levels of Ca2+ loading
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5. Continuous model of cardiac muscle
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6. Continuous model of cardiac muscle
Boundary conditions
Left border:
Right border:
Initial conditions
Local parameters
Global parameter
Isometric conditions
15/10/2012
Роль взаимодействия волн в функции миокарда

7. Model of tissue in study of cardiac pathology
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8. Conclusion
The results obtained in the model suggest that ectopic activity may emerge in a sub-critical myocardial region, e.g. comprising cardiomyocytes with moderately depressed sodium-potassium pump, due to its mechanical interactions in the myocardial tissue.
Moreover, such ectopic zone may expand by capturing normal regions in myocardium via the electro-mechanical coupling between cardiomyocytes.
15/04/2014

9. THANK YOU for ATTENTION!
Supported by the RFBR ( , , ), by Presidium of UBRAS (12-M , 12-П ) and by UrFU (Act 211 Government of RF #02.A ).
15/04/2014