CHORDAL PRESERVATION DURING MITRAL VALVE REPLACEMENT--EFFECT ON LV FUNCTION

二尖瓣置换术期间的腱索保护——对左心室功能的影响

• 批准号: 3899192
• 负责人: H A HENNEIN
• 金额: --
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3899192
• 关键词: Mammalia; disease /disorder model; heart circulation; heart function; heart imaging /visualization /scanning; heart preservation; heart prosthesis; heart surgery; heart valve transplantation; hemodynamics; sheep; tendon injury

To assess the relative contribution of the chordal structures and mitral valve apparatus to left ventricular function (LVF), in the presence of chronic mitral regurgitation (CMR), 18/26 animal models of CMR were developed by creating a 4mm perforation of the anterior mitral valve leaflet during cardiopulmonary bypass. Complete hemodynamic, ultrasonographic, and radionuclide functional analysis will be performed on a control group of animals and in all survivors of the perforation operation to evaluate the effects of CMR on LVF. Data acquired to date show that a 70-80% survivorship was attained in 20-25kg animals, and over 90% in 25-30kg animals. Acute changes in LVF included a drop in dP/dt, while cardiac output remain unchanged. Right heart, left atrial and wedge pressure increased. The second phase of the study consists of performing mitral valve replacement (MVR) in 18 control animals, half of which will be randomized to chordal preservation and half to standard native- valve-removal. The study arm consists of randomization of the CMR animals to these same two groups. Studies of LV function and geometry along with nuclear angiographic data will be obtained and analyzed, to assess whether chordal preservation during MVR has any effect on subsequent LVF in normal volume overloaded ventricles.

评估弦结构的相对贡献和 二尖瓣装置与左心功能(LVF) 存在慢性二尖瓣反流(CMR)，18/26动物模型 通过在前部形成一个4 mm的穿孔来形成CMR 体外循环中的二尖瓣瓣叶。完成 血流动力学、超声和放射性核素功能分析 将在一组对照动物身上和在所有 以评估穿孔手术的幸存者的疗效 LVF上的CMR。 迄今为止获得的数据显示，它们的存活率达到了70%-80%。 在20-25公斤级动物中，在25-30公斤级动物中达到90%以上。剧烈变化 LVF中包括dp/dt下降，而心输出量保持不变 保持不变。右心、左房和楔压升高。 研究的第二阶段包括二尖瓣手术。 替换(MVR)18只对照动物，其中一半将是 随机保存弦乐，一半保存标准原生音乐- 瓣膜摘除。研究ARM由CMR的随机化组成 同样的两组动物。左心功能和心功能的研究 将获得几何学和核血管造影数据，并 分析，以评估MVR过程中的脊索保存是否有 在正常容量超负荷的情况下对随后的LVF的影响。