Modeling hypothermia induced effects for the heterogeneous ventricular tissue from cellular level to the impact on the ECG

PLoS One. 2017 Aug 16;12(8):e0182979. doi: 10.1371/journal.pone.0182979. eCollection 2017.

Abstract

Hypothermia has a profound impact on the electrophysiological mechanisms of the heart. Experimental investigations provide a better understanding of electrophysiological alterations associated with cooling. However, there is a lack of computer models suitable for simulating the effects of hypothermia in cardio-electrophysiology. In this work, we propose a model that describes the cooling-induced electrophysiological alterations in ventricular tissue in a temperature range from 27°C to 37°C. To model the electrophysiological conditions in a 3D left ventricular tissue block it was essential to consider the following anatomical and physiological parameters in the model: the different cell types (endocardial, M, epicardial), the heterogeneous conductivities in longitudinal, transversal and transmural direction depending on the prevailing temperature, the distinct fiber orientations and the transmural repolarization sequences. Cooling-induced alterations on the morphology of the action potential (AP) of single myocardial cells thereby are described by an extension of the selected Bueno-Orovio model for human ventricular tissue using Q10 temperature coefficients. To evaluate alterations on tissue level, the corresponding pseudo electrocardiogram (pECG) was calculated. Simulations show that cooling-induced AP and pECG-related parameters, i.e. AP duration, morphology of the notch of epicardial AP, maximum AP upstroke velocity, AP rise time, QT interval, QRS duration and J wave formation are in good accordance with literature and our experimental data. The proposed model enables us to further enhance our knowledge of cooling-induced electrophysiological alterations from cellular to tissue level in the heart and may help to better understand electrophysiological mechanisms, e.g. in arrhythmias, during hypothermia.

MeSH terms

  • Action Potentials
  • Algorithms
  • Animals
  • Chickens
  • Electrocardiography*
  • Heart Block / physiopathology
  • Heart Conduction System / physiopathology
  • Heart Ventricles / physiopathology*
  • Hypothermia, Induced / adverse effects*
  • Models, Biological
  • Temperature

Grants and funding

This work was funded by the K-Regio-Project of the Standortagentur Tirol, Innsbruck, Austria and by the European Regional Development Fund (ERDF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.