Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Tex; Congenital Heart Surgery, Texas Children's Hospital, Houston, Tex.
Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Tex; Congenital Heart Surgery, Texas Children's Hospital, Houston, Tex.
J Thorac Cardiovasc Surg. 2017 Jul;154(1):291-300. doi: 10.1016/j.jtcvs.2016.12.070. Epub 2017 Mar 11.
The Infant Jarvik 2015 is an implantable axial-flow ventricular assist device (VAD) that has undergone the major evolutionary design modifications to improve hemocompatibility. This study was conducted in anticipation of data submission to the US Food and Drug Administration to obtain Investigational Device Exemption approval.
The VAD was implanted via a left thoracotomy in Barbado sheep (n = 10, 26 (19-34] kg). Anticoagulation was maintained with coumadin, with a target international normalized ratio of greater than the individual sheep's baseline values. The VAD was managed at the highest possible speed as clinically tolerable. Complete necropsy was performed at the end of the study.
There were 2 early mortalities: tension pneumothorax (n = 1) and shower emboli of the fragmented myocardium (n = 1). The remaining 8 sheep (2 with 30-day and 6 with 60-day protocols) completed the anticipated study duration in excellent condition, with the 6 completing 60-day sheep showing appropriate weight gain during support. There were no signs of clinically significant hemolysis, with the final plasma-free hemoglobin of 2 (1-17) mg/dL. Necropsy showed old renal infarction in 7 sheep. Although thromboembolism can be the potential etiology, given the mild anticoagulation regimen, other sources of emboli were identified in 2 sheep (graft coating material and fragmented myocardium). Flow study demonstrated favorable increase in flow (up to 3.0 L/min) in proportion to change in pump speed.
This study has demonstrated that the Infant Jarvik 2015 VAD is capable of maintaining its functionality for an extended period of time with minimal hemolysis.
婴儿 Jarvik 2015 是一种植入式轴流心室辅助装置 (VAD)，它经历了重大的进化设计修改，以提高血液相容性。这项研究是在向美国食品和药物管理局提交数据以获得研究性设备豁免批准之前进行的。
通过左开胸术将 VAD 植入巴巴多斯绵羊（n=10，26（19-34]kg）。用华法林维持抗凝，目标国际标准化比值大于个体羊的基线值。VAD 在临床可耐受的最高速度下进行管理。研究结束时进行全面尸检。
有 2 例早期死亡：张力性气胸（n=1）和碎片心肌的淋浴栓塞（n=1）。其余 8 只绵羊（2 只进行 30 天和 6 只进行 60 天方案）以极佳的状态完成了预期的研究持续时间，其中 6 只完成 60 天的绵羊在支持期间体重增加适当。没有明显的临床显著溶血迹象，最终血浆游离血红蛋白为 2（1-17）mg/dL。尸检显示 7 只绵羊有陈旧性肾梗死。尽管血栓栓塞可能是潜在的病因，但鉴于轻度抗凝方案，在 2 只绵羊中发现了其他来源的栓塞物（移植物涂层材料和碎片心肌）。流量研究表明，随着泵速的变化，流量以有利的方式增加（高达 3.0L/min）。
这项研究表明，婴儿 Jarvik 2015 VAD 能够在最小的溶血情况下维持其功能很长一段时间。
