Elevated Strain and Structural Disarray Occur at the Right Ventricular Apex.
Elevated Strain and Structural Disarray Occur at the Right Ventricular Apex.
复制标题
右心室尖部出现应变升高和结构紊乱。
DOI：
10.1007/s13239-011-0081-3
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发表时间：
2012
影响因子：
1.8
通讯作者：
Huang,H
中科院分区：
文献类型：
--
作者：
Hariharan,V;Provost,J;Shah,S;Konofagou,E;Huang,H
右心室尖部（RVA）是心律异常发展的潜在热点。包括心律失常性右室心肌病和Brugada综合征在内的许多疾病都会影响RVA，此外，RVA仍然是一个不完全表征的起搏区域。是否存在这些传导特性背后的结构原因仍未解决。在本研究中，我们描述了右心室壁的力学应变和结构属性，并验证了右心室尖部经历非均匀应变分布和纤维组织改变的假设，从而易受传导改变的影响。机电波成像（EWI），或弹性成像，心脏被用来量化机械应变发生通过心脏周期。组织学和免疫荧光成像技术检查心脏壁结构和连接蛋白的排列。与左心室和中隔相比，右心室机械应变升高并持续整个收缩期。异质应变分布、心肌纤维紊乱和连接蛋白定位改变发生在RVA。混乱和应变分布的改变分别表明右心室顶点的结构强度下降，右心室的机械负荷增加。因此，这些数据证明了为什么右心室尖顶可能特别容易受到传导异常的影响。
The right ventricular apex (RVA) is a potential hot spot for development of cardiac rhythm anomalies. Many conditions, including arrhythmogenic right ventricular cardiomyopathy and Brugada’s syndrome affect the RVA, and further, the RVA remains an incompletely characterized pacing region. Whether there are structural reasons underlying these conduction properties remains unsettled. In the current study, we characterize the mechanical strains and structural attributes of the right ventricular wall, and test the hypothesis that the right ventricular apex experiences heterogeneous strain distributions and altered fiber organization, and is thus susceptible to conduction alterations. Electromechanical wave imaging (EWI), or elastography, of hearts was used to quantify mechanical strains occurring through a cardiac cycle. Histological and immunofluorescence imaging techniques were used to examine cardiac wall structure and arrangement of junctional proteins. Right ventricular mechanical strains were elevated and sustained throughout systole, compared to the left ventricle and septum. Heterogeneous strain distributions, myocardial fiber disarray, and altered junctional protein localization occured at the RVA. Disarray and altered strain distributions suggest decreased structural strength at the right ventricular apex in particular and increased mechanical impositions in the right ventricle, respectively. Thus, these data demonstrate why the right ventricular apex may be particularly vulnerable to conduction abnormalities.