Program

O.22 -- Oral, NCTP-40

Date: Wednesday, 29 July 2015

Time: 16h40 - 17h00

Analysis of Ventricular Tachycardia and Fibrillation by Bivariate Data Analysis

Le Duy Manh (1), A. V. Dvornikov (2), C. K. Chan (3,4), Pik-Yin Lai (3)

(1) Institute of Physics, VAST, Hanoi, Vietnam. (2) Department of Cell and Molecular Physiology, Loyola University School of Medicine 2160 South First Ave., Maywood, IL 60153, USA. (3) Department of Physics and Center for Complex Systems, National Central University Chungli, Taiwan 320, R.O.C. (4) Institute of Physics, Academia Sinica - Nankang, Taipei, Taiwan 115, R.O.C.

Heart is a complex dynamical system that contains many components worked rhythmically in a coordinated manner to produce rhythmic activity for effectively pumping blood, feeding activities of the whole living body with nutrition and oxygen. Under fast electrical pacing, heart shows rich dynamical behaviors due to its instability, such as alternans, tachycardia and fibrillation. Ventricular tachycardia (VT) is the disease that the heart beats much fast than the normal rhythm. If VT lasts for long time, it may develop into much more serious problems such as ventricular fibrillation or even the sudden cardiac death. Ventricular fibrillation (VF) is an extremely serious arrhythmia which is known to be the major cause of sudden cardiac death, and thus the research to understand its mechanism as well as clinical treatments is very important. In our study, VT and VF in isolated rat hearts perfused in the Langendorff system are induced by fast electrical pacing. Electrical signals from right atrium (a site very closed to sinoatrial node) and left ventricle are recorded simultaneously. We find that when there is strong component of ventricular signal detected in the atria one during VT \& VF, the induced VT \& VF is usually not self-terminating. Quantitative criteria for the prediction of self-terminating VF are proposed based on the analysis of bivariate time series (atrial and ventricular signals) by the cross-wavelet and cross-Fourier power spectra methods. The success rate of our prediction is about 80-90%. Our findings suggest that a heart under VF can recover its sinus rhythm only when the sinoatrial node of the heart is not under strong influence of the VF from its ventricle.

Presenter: Le Duy Manh