摘要
目的 探讨心脏垂直移位时血流动力学改变以及对心室形态 ,功能的影响。方法 健康杂种犬 6条 ,开胸后分别比较正常位置 ,心脏垂直位和心脏垂直加整体头低位时的血流动力学变化 ,心腔压力改变和短轴切面心室形态变化。结果 将心脏处于垂直移位时 ,心输出量 ,每搏量 ,平均动脉压出现显著下降。心脏表面超声显示 :乳头肌中部短轴切面上左、右室的舒张末面积均显著减少。左室舒张末的偏心指数由 0 .99± 0 .2 7升高为1.2 5± 0 .37(P <0 .0 5 )。心脏垂直加头低位时 ,平均动脉压、左室舒张面积和左室舒张末偏心指数可恢复到正常水平。跨室间隔压力差与左室舒张末偏心指数呈显著负相关。结论 心脏垂直移位会产生严重的血流动力学紊乱 ,并伴有心室形态的改变 ;头低位可以部分纠正这些改变。
Purpose To study the effects of vertical displacement of heart on the ventricular geometry and function. Methods Six open-chest,anesthetized dogs were studied.Hemodynamic parameters and ventri-cular geometry were compared at normal position,vertical displacement and Trendelenberg position.The relationship of ventricular pressure and geometry was explored,and how preload impacts on the ventricular pressure and geometry were also examined. Results Cardiac output,mean arterial pressure declined dramatically at vertical displacement of heart comparing with normal position.Left and right ventricular end-diastolic cross-sectional area (determined by epicardial echocardiography) significantly decreased (P<0.05).End-diastolic eccentric index of left ventricle increased from (0.99±0.27) to (1.25±0.37) (P<0.05).Subsequent 20 degrees Trendelenburg position recovered mean arterial pressure,end-diastolic cross-sectional area of left ventricles and eccentric index to the baseline.The diastolic transseptal pressure gradient correlated inversely with the eccentric index. Conclusions Vertical displacement of heart could cause significant hemodynamic deterioration and change ventricular geometry.Trendelenburg position can partially reverse these effects.
出处
《复旦学报（医学版）》
CAS
CSCD
北大核心
2005年第2期209-211,共3页
Fudan University Journal of Medical Sciences
