经导管人工主动脉瓣植入动物的实验方法及影像分析

目的:建立经导管人工主动脉瓣植入的动物实验方法，确定主动脉窦部造影的最佳投射体位，探讨经腹主动脉植入人工主动脉瓣的可行性、安全性。方法: 选取健康杂种大白猪10只，经右侧股动脉送入猪尾巴导管行左心室造影，确定主动脉窦部造影的最佳投射体位，测量主动脉窦部的直径；经右侧股静脉送入临时起搏电极至右心室，选择合适的起搏频率；经腹主动脉送入22F输送鞘管，观察经输送鞘管推送预载瓣膜支架球囊的可行性、安全性。结果: 左心室造影可在左前斜(30±2)°、头位(10±4)°清楚地显示主动脉窦部及冠脉开口。主动脉窦部的直径为（212±23） mm。实验动物可以耐受连续30 s的快速起搏（240~260次/min）。结论: 经腹主动脉途径植入人工主动脉瓣的方法可行、安全。在左前斜(30±2)°、头位(10±4)°可清楚地显示主动脉窦部。以240~260次/min的频率快速起搏可最大限度地减少血流对球囊的冲击，更好地实现瓣膜植入时的精确定位。

Transcatheter artificial aortic valve implantation: animal experiment and image analysis

AIM: To establish a new method of transcatheter aortic valve implantation, to determine the optimal projecting position for the angiography of aortic sinus and to explore the feasibility and safety of this method. METHODS: Ten healthy hybrid pigs were enrolled in this study. A pigtail catheter was placed in the left ventricle through the right femoral artery for ventriculography. The optimal projection position was determined and the diameter of the aortic sinus was measured after left ventriculography. A temporary pacemaker electrode was placed in the right ventricle and the appropriate pacing frequency was selected. A 22F delivery catheter was inserted in the abdominal aorta and a balloon catheter mounted with an artificial valve stent was attempted to be pushed and pulled through the delivery catheter system. RESULTS: Aortic sinus and coronary artery were well demonstrated in the left anterior oblique position (30±2°) plus cranial (10±4°). The diameter of the aortic sinus was (212±23) mm. All pigs enrolled in this study safely endured a rapid pacing frequency (240-260/min) for ~30 sec. CONCLUSION: Implantation of artificial aortic valves through the abdominal aorta is feasible and safe. Aortic sinus and coronary artery are well demonstrated in the left anterior oblique position (30±2°) plus cranial (10±4°). Under the condition of right ventricular rapid pacing, the valve stent could be more accurately implanted into position and the impact of blood flow could be maximally decreased.