Department of Cardiac and Thoracic Vascular Surgery, University of Luebeck, Luebeck, Germany.
Eur J Cardiothorac Surg. 2018 Jul 1;54(1):157-161. doi: 10.1093/ejcts/ezy033.
Transcatheter aortic valve implantation is a treatment strategy for degenerated aortic valve prostheses, but there is some concern regarding valve thrombosis. The optimal anticoagulation strategy for implantation of a transcatheter aortic valve prosthesis remains unclear.
Aortic root models with the Sapien-XT and S3 prostheses (sizes 23 and 26) fixed in a Perimount Magna Ease bioprosthesis (sizes 23 and 25) were constructed. The haemodynamics of the left ventricle were imitated in a proved in vitro model. Milk was used for coagulation after 90s. Different areas of the leaflets (W: wall coagulation, C: commissure coagulation left/right and S: sinus coagulation) were examined and the number of thrombus-like formations was counted.
A total of 54% of the thrombus-like formations were found in the sinus, 28% at the wall area, 13% at the right commissure and 10% at the left commissure. Significant differences were detected at the wall area. S3 prostheses had significantly more thrombus-like formations than the XT prostheses. Additionally, in the S3 prostheses, the thrombus-like formation resembled a film whereas in the XT prostheses, the thrombus-like formation was like the crumbs of a cake. We noted exactly the same pattern in explanted prostheses from patients.
The Sapien prostheses tend to form thromboses due to their flow properties. More than half of the thrombus-like formations were seen in the sinus. The S3 prostheses had significantly more thrombus-like formations than the XT prostheses in the wall area. There are different patterns of thrombus-like formations in XT and S3 prostheses used for transcatheter aortic valve implantation both in vivo and in vitro.
经导管主动脉瓣植入术是治疗退行性主动脉瓣假体的一种治疗策略，但存在一些关于瓣叶血栓形成的担忧。经导管主动脉瓣假体植入的最佳抗凝策略仍不清楚。
构建了带有 Sapien-XT 和 S3 假体（尺寸 23 和 26）的主动脉根部模型，并将其固定在 Perimount Magna Ease 生物假体（尺寸 23 和 25）中。在已验证的体外模型中模拟左心室的血液动力学。90 秒后用牛奶进行凝血。检查了叶片的不同区域（W：壁部凝血，C：左右交界部凝血和 S：窦部凝血）并计算了血栓样形成的数量。
总共发现 54%的血栓样形成位于窦部，28%位于壁部，13%位于右交界部，10%位于左交界部。壁部有显著差异。S3 假体比 XT 假体有更多的血栓样形成。此外，在 S3 假体中，血栓样形成类似于薄膜，而在 XT 假体中，血栓样形成类似于蛋糕屑。我们在从患者体内取出的假体中也注意到了完全相同的模式。
Sapien 假体由于其流动特性容易形成血栓。超过一半的血栓样形成位于窦部。在壁部，S3 假体比 XT 假体有更多的血栓样形成。在经导管主动脉瓣植入术中，体内和体外的 XT 和 S3 假体都存在不同类型的血栓样形成。
