Computer simulation of reentrant activity in SAN Syunyaev R.A., Aliev R. R. Moscow Institute of Physics and Technology, Institute of Theoretical and Experimental Biophysics RAS, Federal Biomedical Agency. 1 Sinoatrial node 2 Reentrant activity in SAN? The model of SAN electrical activity Cm dV i Na dt iCa ,L iCa ,T i f iK ,r iK ,s ito isus iK , ACh ib ,Na ib ,Ca ib ,K iNaK iNaCa i p ,Ca igap iNa – sodium current, iCa,T, iCa,L – calcium Т- and L-type currents, if – funny current, ib,Na, ib,Ca, ib,K – background currents, iK,r, iK,s – rapid and slow potassium inner rectifier currents, ito, isus – 4-AP sensitive currents, iK,АCh – Ach-activated current, iNaK – Na-K pump, iNaCa – Na-Ca exchanger, ip,Ca – calcium pump. gi – gap junctions conductivity, I i gi ( ij )(V Vi ((C )) α – воротные переменные, d (V , C , p ) Vi – Nernst potential, dt ( V , C , p ) Сo,Ci – intrra- and extracellular ionic RT Co concentrations. Vi ln( ) zF Ci Р.Р. Алиев «Концептуальные и детальные модели электрической активности миокарда», 2012, ISBN:978-3-8465-3943-9 6 Модель клеток СУ, связанных щелевыми контактами •15 ion currents. •Sarcoplasmic reticulum. •Intracellular homeostasis (Na, K, Ca ions). •Difference between central and peripheral cels. 7 Phase and trigger waves k k=0.72 mm-1 2 k=3.2 mm-1 8 Syunyaev R.A., Aliev R.R. «Action potential propagation and phase dynamics in the sinoatrial node.» Russian Journal of Numerical Analysis and Mathematical Modelling, 27(5), 493-506, 2012. Dispersion curves Central cells Peripherial cells 9 Syunyaev R.A., Aliev R.R. «Action potential propagation and phase dynamics in the sinoatrial node.» Russian Journal of Numerical Analysis and Mathematical Modelling, 27(5), 493-506, 2012. Reentant activity in SAN (model) R. A SYUNYAEV, R. R. ALIEV «Computer simulation of 3D electrical activity in the sinoatrial node», Russian Journal of Numerical Analysis and Mathematical Modelling, Vol. 26, No.6, pp. 575-587 (2011). 10 11 SAN reentrant activity (experiment) Glukhov et. Al., «Sinoatrial Node Reentry in a Canine Chronic Left Ventricular Infarct Model: The Role of Intranodal Fibrosis and Heterogeneity of Refractoriness», Circulation 2013 Oct;6(5):984-94. SAN+atrium reentry 0.3 s 1.5 s 3.1 s 4.2 s Computer simulation of microreentry in the sinoatrial node. Biophysics, 57(5), 676-680, 2012. Tissue size: 250x250 cells 12 Period of oscillations 14 ACh effect on reentry Computer simulation of microreentry in the sinoatrial node. Biophysics, 57(5), 676-680, 2012. Geometry from: Dobrzynsky et.al., Computer three-dimensional reconstruction of the sinoatrial node. Circulation. 2005 Feb 22;111(7):846-54. 15