心尖轴流泵的解剖相容性及对心肌损伤的动物实验观察

Study of Anatomic Fit of Micro Apex Pump and Surgical Injure in Animal Implantation Experiments

目的:通过动物体内植入实验观察笔者研制的心尖微型轴流泵式心脏辅助装置的可植入性及对动物机体的损伤。方法:动物实验采用的心尖微型轴流泵呈圆柱形,外壳由钛合金制成,直径为18.4～20.6mm。实验动物采用普通家猪,质量为(65±5)kg。全麻下经右侧第5肋间开胸,用12mm直径人造血管与胸降主动脉行"端-侧"吻合。然后切开心包,在左心尖部用特制的环形刀将直径约为15mm的心肌切除,肝素化后将泵通过切口插入左心室,使入口与心室相通。间断缝合泵的环状缝合裙与心肌后严密止血。开始启动血泵后去除人造血管的阻断钳。调节泵转速,测定心腔压力。结果:总共6只动物均顺利完成手术植入,术中未发生不可控制的大出血。表明在非体外循环下植入心尖轴流泵的方法安全可靠。动物实验的压力测试表明:血泵可充分降低左心室压力负荷,维持稳定的外周血压。结论:心尖轴流泵结构设计可行,体积与质量小,可植入性和流体力学特性基本达到实用要求。

Objective Micro apex pump is a new type of micro-axial flow pump,intented to be implanted in left ventricular apex.The surgical implantation of this pump and its physiological performance was studed.Methods After the animal,swines of weight between 60-70 kg,was anesthetized intravenously,respiration was maintained with a volume-limited ventilator via a tracheotomy tube.The left chest was entered through a posterolateral thoracotomy at the fifth costal space.A section of artificial blood vessel was connected to the descending thoracic aorta by a side-to-end anastomosis.Then,the axial flow pump was inserted into the left ventricular through a circular cut at the ventricular apex.Catheter for pressure records was inserted into the aortic arch via the right femoral artery and into the left ventricular via the left atrium for aortic and left ventricular pressure moitoring.Results The testing in a mock circulation suggest that the apex pump is excellent of hydrodynamic characteristics.The surgical implantation of Apex pump was feasible and uneventfully in six of the eight animals.The preliminary in vivo study shows that significant change in the left ventricular pressure can be produced by the operation of pump.The left ventricular systolic pressure was greatly decreased with the increase of pump speed while the aortic pressure remained normal,indicating that the axial pump can effectively unload the ventricle and sustain the circulation.Conclusion Apex pump has a good anatomy fit and was promise to be used in the clinical practice in near future.