MATHEMATICAL APPROACH TO CARDIOVASCULAR MECHANICS

整体目标是：(A)引入新概念 并检验收缩期心肌僵硬的假设结束 与收缩末期应力无关的收缩期心肌硬度 (B)测试这一概念和收缩末期P-V的有效性 病理状态下的关系。(C)建立机械设备 和血流动力学在稳定期和失代偿期相关 容量和压力超负荷所致的左室肥厚状态 在有意识的狗身上。 将在容量过载模型(AV)中进行系列研究 瘘管或主动脉瓣返流)和压力超负荷模型 (腹主动脉缩窄和肾周高血压)。心力衰竭会 通过将体积超负荷叠加到狗身上而诱导 严重的主动脉狭窄和代偿性左心室肥厚。LV 体积计算将基于超声尺寸 技术和电影摄影术。 需要对心肌功能进行更可靠的评估 慢性左心室患者瓣膜置换术的最佳时机选择 体积过载或压力过载。这些研究将提供 为开发新的心肌功能奠定坚实的基础 参数，以及对机制的更好理解 参与左心室肥厚。

The overall objectives are (a) to introduce the new concept of systolic myocardial stiffness and test the hypothesis that end systolic myocardial stiffness in independent of end systolic stress (b) test the validity of this concept and the end systolic P-V relationship in the pathologic state. (c) establish the mechanical and hemodynamic correlates during the stable and decompensated states of LV hypertrophy induced by volume and pressure overload in conscious dogs. Serial studies will be conducted in the volume-overload model (AV fistula or aortic regurgitation) and pressure-overload models (aortic banding and perinephritic hypertension). Heart failure will be induced by superimposing a volume overload on dogs with severe aortic stenosis and compensated LV hypertrophy. LV volume calculations will be based on both the ultrasonic dimension technique and cineventriculography. More reliable assessments of myocardial function are needed for optimum timing of valve replacement in patients with chronic LV volume overload or pressure overload. These studies will provide a sound basis for the development of new myocardial function parameters, and a better understanding of the mechanisms involved in LV hypertrophy.