Abstract
Duchenne muscular dystrophy (DMD) is a progressive muscle disease caused by mutations in the dystrophin gene. Cardiomyopathy, conduction abnormalities, and ventricular arrhythmias are significant complications of this disease. The mdx ( 5cv ) mouse carries a dystrophin mutation and demonstrates a more severe phenotype than the classic mdx mouse. Comprehensive electrophysiological phenotyping was performed in adult mdx ( 5cv ) and wildtype mice, including electrocardiography (ECG), implantable Holter monitoring, intracardiac electrophysiological testing, echocardiography, and exercise treadmill testing. ECG performed in mdx ( 5cv ) mice revealed significantly shorter PR intervals and prominent R waves in surface lead V1. During electrophysiological testing, mdx ( 5cv ) mice exhibited longer ventricle effective refractory periods and mildly increased ventricular tachycardia inducibility. There was no evidence for cardiomyopathy or ventricular dysfunction on echocardiography. Histopathology showed no increased myocardial fibrosis. Exercise endurance was lower in mdx ( 5cv ) mice without arrhythmias or other cardiac abnormalities. Taken together at the age range examined, mdx ( 5cv ) mice exhibit discrete cardiac electrophysiological dysfunction but display no evidence of structural or contractile abnormalities. Thus, the mdx ( 5cv ) mouse recapitulates some of the electrophysiological, but not hemodynamic cardiac defects present in human DMD. In certain settings, the mdx ( 5cv ) mouse may be an appropriate subject for studying electrical pathophysiology and therapy of the cardiac complications of DMD.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of Interventional Cardiac Electrophysiology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.