Clinic for Cardiothoracic and Vascular Surgery, University Hospital RWTH Aachen, Aachen, Germany.
J Thorac Cardiovasc Surg. 2010 Jul;140(1):97-102. doi: 10.1016/j.jtcvs.2009.09.037. Epub 2009 Nov 11.
Transcatheter replacement or repair of mitral valve regurgitation has proved demanding. We aimed for a new approach to anchor a biologic heart valve in the mitral position by inserting a valve-carrying hollow body into the left atrium. This approach was investigated in both a simulation and an animal model.
After creating a mold representing the porcine left atrium from the pulmonary veins as far as the mitral valve, a nitinol skeleton was sutured onto interlaced yarns of polyvinylidene fluoride fitting the mold. The resulting device was equipped with a commercially available stentless valve (25 mm) and investigated in a simulator regarding basic functionality. Furthermore, the device was implanted in 8 female pigs through incision of the left atrium during extracorporeal circulation. Before implantation, artificial regurgitation was created by means of excision from the posterior mitral leaflet. Hemodynamic, echocardiographic, and radiologic examinations followed. For a postmortem examination, the entire heart and the lungs were excised.
We could demonstrate the functionality of the heart valve in a complex, collapsible, and self-expanding hollow body. The device adapted to the surrounding structures, leading to an exclusion of the left atrium. Sufficient treatment of mitral regurgitation was monitored hemodynamically and by means of echocardiographic analysis, although overall visualization remained difficult. Therefore in 4 animals computed tomographic scans were performed. Autopsy revealed proper positioning without major trauma to the surrounding structures.
Anchoring an additional heart valve in the atrioventricular position does not necessarily need to be performed in the heart valve structure itself. Placement of an additional valve in the mitral position is feasible through this approach.
经导管二尖瓣反流置换或修复一直颇具挑战性。我们旨在探索一种新方法，通过将带瓣中空体插入左心房，将生物心脏瓣膜锚定于二尖瓣位置。我们在模拟和动物模型中对此方法进行了研究。
在创建了一个从肺动脉到二尖瓣的猪左心房模型后，将镍钛诺骨架缝合到交错的聚偏二氟乙烯纤维上，以适应模具。所得装置配备了一种市售的无支架瓣膜（25 毫米），并在模拟器中对其基本功能进行了研究。此外，该装置通过体外循环期间对左心房进行切开，在 8 头雌性猪中进行了植入。在植入之前，通过从后二尖瓣叶切除来创建人工反流。随后进行了血流动力学、超声心动图和放射学检查。为了进行尸体检查，整个心脏和肺都被切除。
我们能够证明心脏瓣膜在复杂、可折叠和自扩张的中空体中的功能。该装置适应周围结构，导致左心房被排除在外。通过血流动力学和超声心动图分析监测到二尖瓣反流得到充分治疗，尽管总体可视化仍然困难。因此，在 4 只动物中进行了计算机断层扫描检查。尸检显示位置适当，周围结构无重大创伤。
在房室位置锚定额外的心脏瓣膜不一定需要在心脏瓣膜结构本身中进行。通过这种方法可以在二尖瓣位置放置额外的瓣膜。
