Abstract：
Current surgical aortic valve (AV) replacement options include bioprosthetic and mechanical heart valves (MHVs), each with inherent limitations. Bioprosthetic valves offer superior hemodynamics but suffer from durability issues, typically initiating deterioration within 7-8 years. MHVs, while durable, necessitate lifelong anticoagulation therapy, presenting risks such as severe bleeding and thromboembolic events. The need for anticoagulants is caused by non-physiological flow through the hinge area during the closed phase and large spikes of regional backflow velocity (RBV) during the closing phase that produces high shear events. This study introduces the iValve, a novel MHV designed to combine the hemodynamic benefits of bioprosthetic valves with the durability of MHVs without requiring anticoagulation. The iValve features eye-like leaflets, a saddle-shaped housing, and an optimized hinge design to enhance blood flow and minimize thrombotic risk. Fabricated using 6061-T6 aluminum and polyether ether ketone (PEEK), twelve iValve iterations were evaluated for their opening and closing dynamics. The reported top-performing prototypes demonstrated competitive performance against industry standards. The proposed iValve prototype exhibited a mean RBV of -4.34 m/s with no spikes in RBV, performing similarly to bioprosthetic valves and significantly outperforming existing MHVs. The iValve\'s optimized design showed a 7-10% reduction in closing time and a substantial decrease in RBV spikes, potentially reducing the need for anticoagulation therapy. This study highlights the iValve\'s potential to revolutionize prosthetic heart valve technology by offering a durable, hemodynamically superior solution that mitigates the drawbacks of current MHVs.
摘要：
目前的外科主动脉瓣（AV）替代方案包括生物假体和机械心脏瓣膜（MHV），每个都有固有的局限性。生物瓣膜提供优越的血液动力学，但遭受耐久性问题，通常在7-8年内开始恶化。MHV,虽然耐用，需要终身抗凝治疗,存在严重出血和血栓栓塞事件等风险。对抗凝剂的需求是由在闭合阶段期间通过铰链区域的非生理流动和在闭合阶段期间产生高剪切事件的区域回流速度(RBV)的大峰值引起的。本研究介绍了iValve，一种新型MHV，旨在将生物瓣膜的血液动力学益处与MHV的耐久性相结合，而无需抗凝。iValve的特点是像眼睛一样的小叶，马鞍形的外壳，和一个优化的铰链设计，以提高血液流动和减少血栓风险。使用6061-T6铝和聚醚醚酮（PEEK）制造，评估了12次iValve迭代的打开和关闭动力学。报告的性能最佳的原型显示了与行业标准相比的竞争性能。拟议的iValve原型显示平均RBV为-4.34m/s，RBV没有尖峰，与生物人工瓣膜相似，并且明显优于现有的MHV。iValve的优化设计显示关闭时间减少7-10%，RBV尖峰大幅减少，有可能减少抗凝治疗的需要.这项研究强调了iValve的潜力，通过提供耐用的，血液动力学优越的解决方案，减轻了当前MHV的缺点。
