本文選題：人工心臟泵　切入點：輔助水平　出處：《北京工業(yè)大學》2014年碩士論文　論文類型：學位論文

【摘要】：心室輔助會改變左心室血流動力學特性，但其機理目前卻并不明確。本論文的目標是闡明人工心臟泵輔助水平對左心室血流動力學特性的影響規(guī)律。為此本論文展開如下的研究： 利用有限元仿真軟件ADINA實施在健康、心衰以及人工心臟泵不同輔助水平下的左心室及內部血液的流固耦合數值仿真并對結果進行分析。 本論文的研究結果獲得如下結論： 第一，人工心臟泵輔助改變了心室內壓力。20%和55%輔助水平下的左心室壓力高于心衰時的左心室壓力，在輔助水平為75%、80%以及95%時，左心室壓力低于心衰時的左心室壓，整體上，隨著輔助水平增加，左心室壓力呈現遞減趨勢，高輔助水平可以改善心室卸載； 第二，人工心臟泵輔助改變了心室內流量。在充盈期，隨著輔助水平增加，，二尖瓣入口處體積流速持續(xù)增加；在射血期，隨著輔助水平增加，主動脈瓣出口體積流速持續(xù)減小，射血時間延長，泵血量增加，人工心臟泵輔助可以改善器官灌注； 第三，人工心臟泵輔助改變了左心室壁面切應力。隨著輔助水平增加，壁面切應力持續(xù)降低，此外，在高輔助水平下，赤道面至心尖區(qū)域壁面無壁面切應力分布； 第四，人工心臟泵輔助改變了心室內漩渦。在健康狀態(tài)下，二尖瓣入口處產生兩個漩渦，從正面觀察，上側漩渦順時針轉動，下側漩渦逆時針轉動，充盈結束時，漩渦有最大面積，健康狀態(tài)下，漩渦存在時間最長，在充盈結束時漩渦運動至心尖位置，提高心尖處血流流動，降低血栓產生的可能性；在低輔助水平時（20%和55%），存在兩個漩渦，但是漩渦不能運動至心尖位置，導致心尖存在血液停滯區(qū)；在高輔助水平時（85%和95%），由于主動脈瓣提前打開，上側的漩渦在運動過程中受到出口處血流影響，漩渦的形狀受到影響，同時漩渦不能運動至心尖位置，使得心尖處存在血液停滯區(qū)；在75%輔助水平時，漩渦的運動和健康時類似，它在充盈末期能運動至心尖，保證了心尖處血流流動。
[Abstract]:Ventricular assist changes left ventricular hemodynamics, But the mechanism is not clear at present. The aim of this thesis is to clarify the influence of the auxiliary level of artificial heart pump on left ventricular hemodynamics. Finite element simulation software ADINA was used to simulate the fluid-solid coupling of left ventricle and internal blood at different levels of health, heart failure and artificial heart pump, and the results were analyzed. The research results of this thesis are as follows:. First, the artificial heart pump adjuvant changes the left ventricular pressure at 20% and 55% auxiliary levels, which is higher than the left ventricular pressure at heart failure. At the auxiliary level of 75% or 80% and 95%, the left ventricular pressure is lower than the left ventricular pressure at heart failure as a whole. With the increase of auxiliary level, the pressure of left ventricle decreased, and high auxiliary level could improve the unloading of ventricle. Second, the artificial heart pump adjusts the flow in the ventricle. During the filling period, with the increase of the auxiliary level, the volume velocity of the mitral valve inlet continues to increase, and during the ejection period, with the increase of the auxiliary level, The volume velocity of aortic valve outlet continuously decreased, the ejection time prolonged, the pump blood volume increased, the artificial heart pump can improve the organ perfusion. Thirdly, the wall shear stress of the left ventricular wall was changed by the artificial heart pump. With the increase of the auxiliary level, the wall shear stress continued to decrease, in addition, there was no wall shear stress distribution from the equator to the apical region at the high auxiliary level. In 4th, the artificial heart pump helped change the swirl in the ventricle. In a healthy state, two swirls occur at the entrance of the mitral valve, viewed from the front, turning clockwise on the upper side, turning counterclockwise on the lower side, and turning at the end of the filling. The whirlpool has the largest area. In healthy condition, the vortex exists for the longest time. At the end of filling, the vortex moves to the apical position, increases the flow of blood flow at the apex, and reduces the possibility of thrombosis. At the low auxiliary level, there are two whirlpools, 20% and 5550%. However, the vortex can not move to the apical position, leading to the existence of a blood stagnation area at the apical point. At the high auxiliary level, 85% and 95% of the aortic valve opens ahead, and the upper vortex is affected by the blood flow at the outlet during the course of movement. The shape of the vortex is affected, and the vortex is unable to move to the apical position, resulting in a blood stagnation zone at the apical point; at the 75% auxiliary level, the vortex moves like a healthy one, moving to the apex at the end of filling. The blood flow at the apex is guaranteed.
【學位授予單位】：北京工業(yè)大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：R318.11

【引證文獻】

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1 王文鑫;計算流體力學結合病理學對顱內動脈瘤生長及破裂機制的研究[D];中國人民解放軍醫(yī)學院;2015年

相關碩士學位論文 前1條

1 王慧;基于左心室輔助的心血管系統(tǒng)建模與控制策略研究[D];吉林大學;2017年

本文編號：1566370