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Updated: Jun 13, 2026
Ambulatory ECG Recording in Mice
Published on: May 27, 2010
Cardiac conduction disturbances and differential effects on atrial and ventricular electrophysiological properties in
Jan Wilko Schrickel1, Florian Stöckigt, Wieslaw Krzyzak
1Department of Medicine-Cardiology, University of Bonn, Sigmund Freud Strasse 25, 53105 Bonn, Germany. jan.schrickel@ukb.uni-bonn.de
Insights
Desmin deficiency in mice alters cardiac electrophysiology, leading to reduced atrial and prolonged ventricular refractory periods. This desmin deficiency results in increased atrial fibrillation but decreased ventricular arrhythmias, differing from human desminopathies.
Area of Science:
- Cardiology
- Molecular Biology
- Genetics
Background:
- Desmin is a crucial intermediate filament protein in striated muscle cells and the cardiac conduction system.
- Mutations in desmin cause desmin-related cardiomyopathy, leading to heart failure and arrhythmias in humans.
Purpose of the Study:
- To investigate the electrophysiological consequences of desmin deficiency in a mouse model.
- To characterize cardiac electrical properties in desmin-deficient (Des-/-) mice compared to wild-type (Des+/+) controls.
Main Methods:
- In vivo electrophysiological studies were conducted on 29 Des-/- and 19 Des+/+ mice.
- Epicardial activation mapping was performed on Langendorff-perfused hearts to assess conduction velocity.
Main Results:
- Des-/- mice showed significantly reduced atrial refractory periods (23.6 ms vs. 31.8 ms) and prolonged ventricular refractory periods (33.0 ms vs. 26.7 ms).
- Atrial fibrillation inducibility was higher in Des-/- mice (38% vs. 27%), while ventricular tachycardia inducibility was lower (7% vs. 21%).
- Epicardial mapping revealed slowed ventricular conduction in Des-/- mice.
Conclusions:
- Desmin deficiency alters cardiac electrophysiology, characterized by changes in refractory periods and conduction slowing.
- The observed electrophysiological profile in Des-/- mice, including enhanced atrial fibrillation and reduced ventricular arrhythmias, differs from human desminopathies.
- These findings suggest that functional alterations, not merely the loss of desmin, may underlie cardiac pathology in human desminopathies.
Purpose:
Desmin mutations in humans cause desmin-related cardiomyopathy, resulting in heart failure, atrial and ventricular arrhythmias, and sudden cardiac death. The intermediate filament desmin is strongly expressed in striated muscle cells and in Purkinje fibers of the ventricular conduction system. The aim of the present study was to characterize electrophysiological cardiac properties in a desmin-deficient mouse model.
Methods:
The impact of desmin deficiency on cardiac electrophysiological characteristics was examined in the present study. In vivo electrophysiological studies were carried out in 29 adult desmin deficient (Des-/-) and 19 wild-type (Des+/+) mice. Additionally, epicardial activation mapping was performed in Langendorff-perfused hearts.
Results:
Intracardiac electrograms showed no significant differences in AV, AH, and HV intervals. Functional testing revealed equal AV-nodal refractory periods, sinus-node recovery times, and Wenckebach points. However, compared to the wild-type situation, Des-/- mice were found to have a significantly reduced atrial (23.6+/-10.3 ms vs. 31.8+/-12.5 ms; p=0.045), but prolonged ventricular refractory period (33.0+/-8.7 ms vs. 26.7+/-6.5 ms; p=0.009). The probability of induction of atrial fibrillation was significantly higher in Des-/- mice (Des-/-: 38% vs. Des+/+: 27%; p=0.0255), while ventricular tachycardias significantly were reduced (Des-/-: 7% vs. Des+/+: 21%; p<0.0001). Epicardial activation mapping showed slowing of conduction in the ventricles of Des-/- mice.
Conclusions:
Des-/- mice exhibit reduced atrial but prolonged ventricular refractory periods and ventricular conduction slowing, accompanied by enhanced inducibility of atrial fibrillation and diminished susceptibility to ventricular arrhythmias. Desmin deficiency does not result in electrophysiological changes present in human desminopathies, suggesting that functional alterations rather than loss of desmin cause the cardiac alterations in these patients.
