INFERIOR VENA CAVA FILTRATION WITH A REMOVABLE DEVICE

描述（改编自申请人摘要）：将开发一种可拆卸的下腔静脉过滤器，以防止暂时有发生这种危及生命的并发症风险的患者发生肺栓塞。特殊的设计避免了永久性过滤器的长期不良影响，特别是小洞堵塞。它克服了其他临时过滤器的局限性，在存在被困凝块的情况下，要么必须永久植入，要么必须冒着引发肺栓塞的风险移除，它们是为了防止肺栓塞。在美国，每年有多达100万患者可能是这种装置的候选对象。本研究的目的是完善原型系统的设计，以达到最佳的疗效和安全性。捕获效率和可回收性将在使用标准化凝块制剂和人肺凝块的生理体外模拟中进行测试。诱捕效率、可回收性、迁移和内皮生长将在急性和慢性绵羊模型中进行测试，设备停留时间长达四周。完成后，申请人将证明临时腔静脉过滤系统的可行性，该系统可以捕获血块并允许血块清除。该项目将为未来的临床评估和商业化提供一个完善的、特性良好的、已知疗效的系统。拟议的商业应用：肺血栓栓塞的危险因素包括固定、骨科或腹部手术、脊髓损伤、多发性创伤、心脏病和肿瘤。这种可移动过滤器有利于有暂时肺栓塞风险的患者。最大的目标人群是下肢骨科大手术患者。1994年，在非联邦短期住院医院，474 000名患者接受了下肢关节置换术，89 000名患者接受了其他下肢修复术；此外，27,000名有妊娠期和产褥期并发症的患者将符合资格。考虑到多发创伤患者和腹部手术患者发生血栓栓塞的风险较高，每年的目标患者总数远远超过60万。这些患者都有发展为深静脉血栓和随后的肺栓塞的风险。额外的目标患者是那些在医院已经知道有深静脉血栓形成的人，估计每年有50万人。即使这110万患者中只有1/10会被转诊放置临时过滤器，每年也需要超过11万个过滤器。永久过滤器的成本在600美元到1400美元之间。一个高效实用的可移动过滤系统仅在美国每年就能带来6千万到1.4亿美元的市场机会。

DESCRIPTION (adapted from applicant's abstract): A removable inferior vena cava filter will be developed to prevent pulmonary embolism in patients who are temporarily at risk to develop this life-threatening complication. The specific design avoids long-term adverse effects of permanent filters, especially cavel occlusion. It overcomes limitations of other temporary filters which, in presence of trapped clot, either must be implanted permanently or be removed at risk of precipitating the pulmonary embolism they were intended to prevent. Up to 1 million patients per year in the United States may be candidates for such a device. The objective of this research is to refine the design of a prototype system towards optimal efficacy and safety. Trapping efficiency and retrievability will be tested in a physiologic in vitro simulation using standardized clot preparations and human pulmonary clot. Trapping efficiency, retrievability, migration, and endothelial ingrowth will be tested in an acute and chronic sheep model with device dwell times up to four weeks. On completion the applicant will have demonstrated feasibility of a temporary caval filter system that catches clot and permits clot removal. The project will provide a refined and well-characterized system with known efficacy as basis for future clinical evaluation and commercialization. PROPOSED COMMERCIAL APPLICATION: Risk factors for pulmonary thromboembolism include immobilization, orthopedic or abdominal surgery, spinal cord injury, multiple trauma, cardiac disease and neoplasm. the removable filter is to benefit patients with temporary risk of pulmonary embolisms. The largest target group is patients with major lower extremity orthopedic surgery. In 1994, in non-Federal short-stay hospitals, 474,000 patients underwent joint replacement of the lower extremities and 89,000 underwent other repair of lower extremities; in addition 27,000 patients with complications in pregnancy and puerperium would qualify. considering that patients with multiple trauma and those with abdominal surgeries are at higher risk of thromboembolism, the total pool of target patients far exceeds 600,000 per year. These are all patients who are at risk of developing deep venous thrombosis and subsequent pulmonary embolism. Additional target patients are those who already have known deep venous thrombosis in the hospital, an estimated 500,000 annually. Even if only 1/10 of these 1.1 million patients would be referred for placement of the temporary filter, an annual need of more than 110,000 filters would result. Costs of permanent filters range between $600-$1400. An efficient and practical removable filter system could represent an annual market opportunity of 60- 140 million dollars in the United States alone.