Agger Peter, Hyldebrandt Janus Adler, Nielsen Eva Amalie, Hjortdal Vibeke, Smerup Morten
Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Skejby, Aarhus, Denmark.
Interact Cardiovasc Thorac Surg. 2010 Jun;10(6):962-6. doi: 10.1510/icvts.2009.227264. Epub 2010 Mar 2.
The right ventricle (RV) tolerates acute pulmonary valvular regurgitation fairly well, however, in the long-term dilatation and failure often ensues. There is little known of the structural and functional myocardial alterations following this pathophysiology, and therefore animal models are sought. We aimed to develop an animal experimental model for RV dilatation emphasizing feasibility, reproducibility and human compatibility. Free pulmonary valve insufficiency and RV dilatation were created with a novel external suture plication technique in nine 5 kg piglets. Six matched animals served as controls. After 10 weeks cardiac dimensions and physiology were assessed with in vivo cardiovascular MRI and conductance technique. RV end-diastolic volume increased 31% in the intervention group (P=0.03). The regurgitation fraction was 37% in the intervention group compared to -2% in controls (P<0.001). Conductance measurements showed preserved RV contractile function, but significant left ventricular diastolic impairment. This study is the first to show that pulmonary valve regurgitation, RV dilatation and functional impairment can be achieved by external leaflet plication. Compared to known methods, the advantages of this model are: 1) no induction of stenosis over time, 2) no risk of stent migration, and 3) very simple and reproducible.
右心室（RV）对急性肺动脉瓣反流的耐受性相当良好，然而，长期来看往往会出现扩张和功能衰竭。对于这种病理生理过程后心肌的结构和功能改变，人们了解甚少，因此需要寻找动物模型。我们旨在开发一种用于右心室扩张的动物实验模型，强调可行性、可重复性和与人体的兼容性。采用一种新型的外部缝合折叠技术，在9只5千克重的仔猪身上造成游离肺动脉瓣关闭不全和右心室扩张。6只匹配的动物作为对照。10周后，采用体内心血管磁共振成像和电导技术评估心脏大小和生理功能。干预组右心室舒张末期容积增加了31%（P = 0.03）。干预组的反流分数为37%，而对照组为 -2%（P < 0.001）。电导测量显示右心室收缩功能保留，但左心室舒张功能有显著损害。本研究首次表明，通过外部瓣叶折叠可实现肺动脉瓣反流、右心室扩张和功能损害。与已知方法相比，该模型的优点是：1）不会随时间推移诱发狭窄；2）没有支架移位的风险；3）非常简单且可重复。
