Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance
Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance
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DOI：
10.1161/jaha.117.006084
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发表时间：
2017-09-01
影响因子：
5.4
通讯作者：
Simon, Marc A.
中科院分区：
文献类型：
--
作者：
Jang, Sae;Vanderpool, Rebecca R.;Simon, Marc A.
背景：右心室舒张功能与肺动脉高压患者的预后相关；然而，右心室生物力学与血流动力学之间的关系尚未得到研究。方法与结果采用肺动脉束带法（PAB，对照组，n=7； PAB, n=5）建立RV压力过载大鼠模型。绑扎后3周，采用导尿管测量右心室血流动力学。获得右心室游离壁心肌的双轴力学特性，推断低应变区和高应变区（分别为E-1和E-2）纵向和周向弹性模量。血液动力学分析显示，PAB组舒张末期弹性（E-ed）显著增加（对照组：55.1 mm Hg/mL[四分位数范围：44.785.4 mm Hg/mL]； PAB组：146.6 mm Hg/mL[四分位数范围：105.8155.0 mm Hg/mL]； P=0.010）。PAB组纵向E1升高（对照组：7.2 kPa[四分位间距：6.718.1 kPa]； PAB组：34.2 kPa[四分位间距：18.144.6 kPa]， P=0.018），而纵向E-2和周向E-1和E-2无显著变化。最后，通过将右心室建模为球体，根据血流动力学数据计算壁应力：（应力=压力x半径/2 x厚度）结论：PAB大鼠右心室压力过载导致舒张期心肌刚度增加，这既反映在血流动力学上，通过增加E-ed，也反映在生物力学上，通过增加纵向E-1。组织生物力学刚度的适度增加与E-ed的大幅增加有关。右心室舒张功能的血流动力学测量可用于预测心肌的生物力学变化。
Background Right ventricular (RV) diastolic function has been associated with outcomes for patients with pulmonary hypertension; however, the relationship between biomechanics and hemodynamics in the right ventricle has not been studied.Methods and Results Rat models of RV pressure overload were obtained via pulmonary artery banding (PAB; control, n=7; PAB, n=5). At 3 weeks after banding, RV hemodynamics were measured using a conductance catheter. Biaxial mechanical properties of the RV free wall myocardium were obtained to extrapolate longitudinal and circumferential elastic modulus in low and high strain regions (E-1 and E-2, respectively). Hemodynamic analysis revealed significantly increased end-diastolic elastance (E-ed) in PAB (control: 55.1 mm Hg/mL [interquartile range: 44.785.4 mm Hg/mL]; PAB: 146.6 mm Hg/mL [interquartile range: 105.8155.0 mm Hg/mL]; P=0.010). Longitudinal E1 was increased in PAB (control: 7.2 kPa [interquartile range: 6.718.1 kPa]; PAB: 34.2 kPa [interquartile range: 18.144.6 kPa]; P=0.018), whereas there were no significant changes in longitudinal E-2 or circumferential E-1 and E-2. Last, wall stress was calculated from hemodynamic data by modeling the right ventricle as a sphere: (stress = Pressure x radius/2 x thicknessConclusions RV pressure overload in PAB rats resulted in an increase in diastolic myocardial stiffness reflected both hemodynamically, by an increase in E-ed, and biomechanically, by an increase in longitudinal E-1. Modest increases in tissue biomechanical stiffness are associated with large increases in E-ed. Hemodynamic measurements of RV diastolic function can be used to predict biomechanical changes in the myocardium.