Effects of Left Ventricular Hypertrophy and Myocardial Stiffness on Myocardial Strain Under Preserved Ejection Fraction
Effects of Left Ventricular Hypertrophy and Myocardial Stiffness on Myocardial Strain Under Preserved Ejection Fraction
复制标题
左心室肥厚和心肌僵硬对保留射血分数下心肌应变的影响
DOI：
10.1007/s10439-020-02706-7
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发表时间：
2021
影响因子：
3.8
通讯作者：
Wada Shigeo
中科院分区：
文献类型：
--
作者：
Morishita Takaomi;Takeishi Naoki;Ii Satoshi;Wada Shigeo
尽管对射血分数保留型心力衰竭（HFpEF）进行了大量的实验观察，其主要特征是左心室肥厚且左心室射血分数超过50%，但HFpEF下的心肌动力学尚未完全阐明，特别是心肌应变分布与心肌做功之间的关系。为了解决这个问题，我们数值研究了在不同机械条件下，例如涉及心肌厚度和心肌纤维弹性的条件下，在收缩期和舒张期末具有固定内容积的心动周期期间心肌应变的径向分布。心肌被建模为粘超弹性连续材料。该模型考虑到沿心肌纤维方向的主动收缩应力取决于膜电位的变化。我们的数值结果表明，随着壁厚度的增加，径向和周向应变均减少，这反映了心脏肥大，但心肌做功变得比薄心室壁观察到的更大。此外，左心室舒张内压的变化引起周向应变，而纤维刚度则导致径向应变。由于峰值周向应变可以通过总内部体积和心肌体积之间的最大差异来很好地估计，因此测量心外膜收缩率应该有助于了解 HFpEF 患者。
Despite numerous experimental observations regarding heart failure with preserved ejection fraction (HFpEF), which is characterized mainly by left ventricular hypertrophy and a left ventricular ejection fraction over 50%, myocardial dynamics under HFpEF have not yet been fully clarified, particularly regarding the relationship between myocardial strain distribution and myocardial work. To address this issue, we numerically investigated radial distribution of myocardial strain during a cardiac cycle with fixed internal volume at the end of the systolic and diastolic phases under different mechanical conditions, such as those involving myocardial thickness and elasticity of myocardial fibers. The myocardium was a modeled as a visco-hyperelastic continuous material. This model was taken into account that active contractile stress along the myocardial fiber direction depends on membrane potential change. Our numerical results showed that both radial and circumferential strains decreased as wall thickness increased, which reflected cardiac hypertrophy, but that myocardial work became larger than that observed with thin ventricular walls. Further, the change in left ventricular diastolic internal pressure caused circumferential strain, while fiber stiffness contributed to radial strain. Since peak circumferential strain was well estimated by the maximum difference between total internal and myocardial volumes, measuring the epicardial contraction rate should be helpful in understanding patients with HFpEF.
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影响因子：
15.9
作者：
Nakao, K;Minobe, W;Leinwand, LA
通讯作者：
Leinwand, LA
影响因子：
2.8
作者：
Brucks, S;Little, WC;Shihabi, ZK
通讯作者：
Shihabi, ZK
影响因子：
24
作者：
Kraigher-Krainer E;Shah AM;Gupta DK;Santos A;Claggett B;Pieske B;Zile MR;Voors AA;Lefkowitz MP;Packer M;McMurray JJ;Solomon SD;PARAMOUNT Investigators
通讯作者：
PARAMOUNT Investigators
影响因子：
4.6
作者：
Guccione, JM;Moonly, SM;Pasque, MK
通讯作者：
Pasque, MK
影响因子：
158.5
作者：
Owan, Theophilus E.;Hodge, David O.;Redfield, Margaret M.
通讯作者：
Redfield, Margaret M.