决定不就是限制了吗？

Ventriculoarterial coupling is the ratio of the arterial elastance (Ea) to the left ventricle (LV) end-systolic elastance (Ees). Ea/Eesexpresses the efficiency of the cardiovascular system in providing adequate peripheral perfusion and oxygen delivery to the organs through the dynamic interaction between the heart and the vascular system. As LV stroke volume (SV) in the steady state is both determined and is limited by arterial pressure, the intersection between stoke volume and arterial pressure represents the end-product of ventriculoarterial coupling in a given patient. As previously demonstrated, the cardiovascular function is optimal when the system is coupled, meaning that Ea/Ees is near the unity (Ea/ Ees=1±0.36) with Ea=2.2±0.8 mmHg/ml and Ees=2.3±1 mmHg/ml [2,5]. This occurs when the continuous modulation of the LV performance to the arterial load provides adequate cardiac output, proper perfusion pressure, and flow distribution to the peripheral organs. In addition,Ea/Ees defines one of the primary determinants of LV energetics, in that mechanical energy needed by the LV to transfer the stoke volume to the arterial system is optimal. This occurs when Eaand Eesare equal to each other. When the dynamic interaction between the heart and the vascular system fails, as seen in different acute and chronic pathologic conditions, changes in Eaand Eesoccur and the system becomes uncoupled (Ea/Ees>1)

心室-动脉耦联是动脉弹性(Ea)与左心室(LV)收缩期末期弹性(Ees)的比值。通过心脏和血管系统之间的动态相互作用，Ea/Ees代表了心血管系统为器官提供充足的周围灌注和氧气输送的效率。由于稳定状态下的左室每搏量(SV)既由动脉压决定，又受动脉压的限制，因此，在特点的患者中，每搏量与动脉压的相互作用就代表了心室-动脉藕联的终产物。正如前面所说，当这一系统藕联良好时，心血管功能最佳，此时Ea / Ees接近1(Ea /Ees=1±0.36)，即Ea=2.2±0.8mmHg/ml、Ees=2.3±1 mmHg/ml。这在左室对动脉负荷的连续调节提供了充足的心输出量、对周围器官合适的灌注压和血流分布时即会发生。此外，Ea/Ees定义了左心室活力的主要决定因素之一，在这个时候左室转送每搏量至动脉系统时所需要的机械能最佳。这发生在Ea与Ees相等时。当心脏和血管系统之间的动态相互作用失效时，也就是在不同的急性和慢性病理条件下，Ea和Ees即会发生改变，这一系统变得失藕联(Ea/Ees >1)。

determined and is limited 决定并限制？决定不就是限制了吗？

unity？1

define 能不能翻译成：是