Regensburg 2007 – scientific programme

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DY: Fachverband Dynamik und Statistische Physik

DY 28: Nonlinear stochastic systems

DY 28.9: Talk

Thursday, March 29, 2007, 16:00–16:15, H2

Theoretical description of the statistics of ventricular beat intervals during atrial fibrillation — •Thomas Hennig and Philipp Maass — Institut für Physik, Technische Universität Ilmenau, 98684 Ilmenau, Germany

Atrial fibrillation (AF) is the most common arrhythmia of the heart. It is characterised by rapid electrical excitations in the atria with a mean fibrillation rate (AF rate) of 3-12 Hz and an irregular relation with respect to the excitations in the ventricles. Recent studies showed that the AF rate is an important parameter for estimating the risk of a transition from paroxysmal to chronical AF and for predicting the probability of a conversion to sinus rhythm by pharmaceutical treatment. In this work it is our goal to determine the AF rate from the statistics of ventricular beat intervals taken from the surface electrocardiogram (ECG) based on a model [1] for the transduction of impulses through the atrio-ventricular node. The model can be rewritten in terms of a first passage time problem for a random walk with moving boundary, which is solved analytically by applying the Wiener-Hopf technique. It successfully reproduces specific characteristics found in the statistics of ventricular beat intervals during AF [2]. Tests with clinical data yield good agreement with the theoretical predictions.

[1]

P. Jørgensen, C. Schäfer, P. G. Guerra, M. Talajic, S. Nattel, L. Glass, Bull. Math. Bio. 64 1083 (2002).

[2]

Th. Hennig, P. Maass, J. Biol. Phys., in press; cond-mat/0605295.