Experimental and theoretical ventricular electrograms and their relation to electrophysiological gradients in the adult rat heart.

Full Abstract

The electrical activity of adult mouse and rat hearts has been analyzed extensively, often as a prerequisite for genetic engineering studies or for the development of rodent models of human diseases. Some aspects of the initiation and conduction of the cardiac action potential in rodents closely resemble those in large mammals. However, rodents have a much higher heart rate and their ventricular action potential is triangular and very short. As a consequence, an interpretation of the electrocardiogram in the mouse and rat remains difficult and controversial. In this study, optical mapping techniques have been applied to an in vitro left ventricular adult rat preparation to obtain patterns of conduction and action potential duration measurements from the epicardial surface. This information has been combined with previously published mathematical models of the rat ventricular myocyte to develop a bidomain model for action potential propagation and electrogram formation in the rat left ventricle. Important insights into the basis for the repolarization waveform in the ventricular electrogram of the adult rat have been obtained. Notably, our model demonstrated that the biphasic shape of the rat ventricular repolarization wave can be explained in terms of the transmural and apex-to-base gradients in action potential duration that exist in the rat left ventricle.

Author information

Author/s: Weber dos Santos, Rodrigo (R); Nygren, Anders (A); Otaviano Campos, Fernando (F); Koch, Hans (H); Giles, Wayne R (WR);

Affiliation: 1Department of Computer Science, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil. rodrigo.weber(-atsign-)ufjf.edu.br

Journal and publication information

Publication Type: In Vitro; Journal Article; Research Support, Non-U.S. Gov't

Journal: American journal of physiology. Heart and circulatory physiology (Am J Physiol Heart Circ Physiol), published in United States. (Language: eng)

Reference: 2009-Oct; vol 297 (issue 4) : pp H1521-34

Dates: Created 2009/09/25; Completed 2009/10/08;

PMID: 19700625, status: MEDLINE (last retrieval date: 10/8/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.