脑动静脉畸形血液动力学研究

An Experimental Study on the hemodynamics of Cerebral Arteriovenous Malformations

目的建立脑动静脉畸形 (AVM )的病理生理学模型 ,检测血液动力学改变。 方法将大鼠左侧颈外静脉与颈总动脉行端侧吻合 ,结扎吻合口近尾端的颈总动脉 ,测定吻合前后及模型动物饲养 16周后的局部脑血流量、右侧颈外静脉压力、颈总动脉压力、颈总动脉的血流速度。 结果大鼠静脉动脉的端侧吻合形成动静脉分流 ,左侧局部脑血流量显著降低 ,右侧颈外静脉压增加、颈总动脉压降低、颈总动脉血流速度增快。 16周后 ,局部脑血流量较动静脉吻合形成后即刻升高 ,右侧颈外静脉压和右颈总动脉血流速度进一步增加 ,右侧颈总动脉压无明显改变。结论大鼠颈部动静脉分流形成低灌注压、高血流量、静脉高压的模型 ,符合AVM的血液动力学特征。长期的脑低灌注压使脑血管反应改变 。

Objective This study was to establish a pathophysiologic model of arteriovenous malformations and measure its hemodynamic changes. Methods The model of carotid-jugular fistula(CJF) in 10 rats was constructed by left external jugular vein (EJV) and common carotid artery (CCA) side to end anastomosis. The left CCA and EJV were ligated as controls in 10 rate.We measured regional blood flow (rCFB), right jugular vein blood pressure (VBP),right carotid artery average blood pressure (ABP) and its blood flow velocity(BFV). Results The overall patency rate of fistula in these 10 rats was 100%. In the CJF group rCBF and ABP declined significantly (P<0.01), VBP ascended (P< 0.05 ),BFV became faster (P<0.01). After 16 weeks rCBF, VBP and BFV were increased more (P<0.05),but ABP had no change. Conclusion This model simulates the pathophysiologic perturbations by cerebral arteriovenous malformations. With this study we found that the cerebral vasoreactivity would be adapted to increase rCBF after long term hypoperfusion resulting from arteriovenous malformations.