Hofferberth Sophie C, Saeed Mossab Y, Tomholt Lara, Fernandes Matheus C, Payne Christopher J, Price Karl, Marx Gerald R, Esch Jesse J, Brown David W, Brown Jonathan, Hammer Peter E, Bianco Richard W, Weaver James C, Edelman Elazer R, Del Nido Pedro J
Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA 02138, USA.
Sci Transl Med. 2020 Feb 19;12(531). doi: 10.1126/scitranslmed.aay4006.
Congenital heart valve disease has life-threatening consequences that warrant early valve replacement; however, the development of a growth-accommodating prosthetic valve has remained elusive. Thousands of children continue to face multiple high-risk open-heart operations to replace valves that they have outgrown. Here, we demonstrate a biomimetic prosthetic valve that is geometrically adaptable to accommodate somatic growth and structural asymmetries within the heart. Inspired by the human venous valve, whose geometry is optimized to preserve functionality across a wide range of constantly varying volume loads and diameters, our balloon-expandable synthetic bileaflet valve analog exhibits similar adaptability to dimensional and shape changes. Benchtop and acute in vivo experiments validated design functionality, and in vivo survival studies in growing sheep demonstrated that mechanical valve expansion accommodated growth. As illustrated in this work, dynamic size adaptability with preservation of unidirectional flow in prosthetic valves thus offers a paradigm shift in the treatment of heart valve disease.
先天性心脏瓣膜病会产生危及生命的后果，因此需要早期进行瓣膜置换；然而，能够适应生长的人工心脏瓣膜的研发一直难以实现。成千上万的儿童仍需面临多次高风险的心脏直视手术，以更换已不再适用的瓣膜。在此，我们展示了一种仿生人工心脏瓣膜，其在几何形状上具有适应性，能够适应身体生长以及心脏内部的结构不对称。受人类静脉瓣膜的启发，其几何形状经过优化，可在不断变化的各种容积负荷和直径范围内保持功能，我们的球囊扩张式合成双叶瓣膜类似物表现出对尺寸和形状变化的类似适应性。台式实验和急性体内实验验证了设计功能，在生长中的绵羊身上进行的体内存活研究表明，机械瓣膜扩张能够适应生长。正如本研究所示，人工心脏瓣膜具有动态尺寸适应性并能保持单向血流，这为心脏瓣膜病的治疗带来了范式转变。
