Left ventricular strain distribution in healthy dogs and in dogs with tachycardia-induced dilated cardiomyopathy

Cardiovascular Ultrasound

Research

James D Thomas¹  Kenya Kusunose¹  Zoran B Popović¹  Youhua Zhang²  Todor N Mazgalev² 

[1]Department of Cardiovascular Medicine, Cleveland Clinic, Heart and Vascular Institute, 9500 Euclid Avenue, Desk J1-5, 44195, Cleveland, OH, USA

[2]Department of Molecular Cardiology, Cleveland Clinic, Heart and Vascular Institute, 44195, Cleveland, OH, USA

关键词: Strain echocardiography;    Twist;    Tachycardia induced cardiomyopathy;   

DOI  :  10.1186/1476-7120-11-43

 received in 2013-10-29, accepted in 2013-11-23,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundRecently, left ventricular (LV) strain distribution pattern has been assessed in several cardiac disease states. Tachycardia-induced cardiomyopathy (TIC) is an animal model of non-ischemic cardiomyopathy well characterized in terms of global LV dysfunction but with poor understanding of regional variability in LV function. We hypothesized that TIC induces specific changes in LV strain distribution pattern.MethodsTwenty five adult mongrel conscious dogs were trained to lie down calmly for echocardiography. In seven selected dogs, we implanted pacing system for TIC induction under general anesthesia. We measured LV geometry and function, strains, and torsion before and after the development of TIC in awake non-sedated state.ResultsIn 25 healthy dogs, all three types of normal strain significantly increased from base to apex (p <0.05), while a definite and recognizable twist could be measured due to presence of shear strain. In 7 dogs with TIC, marked changes in LV mechanics occurred throughout the cardiac cycle, resulting in decrease of strain (p <0.001), twist (p <0.05), and negative peak twist rate (p <0.05). Interestingly, the relative decrease of strain due to TIC was more pronounced in the apex (p < 0.001), with the radial strain decreasing the most (p < 0.05).ConclusionTIC is accompanied by decreased systolic LV strain and twist deformation, as well as loss of early diastolic recoil. In addition, the decrease of strain was more profound in the apex. This “reverse” distribution of LV strain may help us understand LV dysfunction in the presence of nonischemic etiology.

【 授权许可】

Unknown   
© Kusunose et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.