Center for Medical Physics and Biomedical Engineering; Department of Cardiothoracic Surgery, Medical University of Vienna, Vienna, Austria; Ludwig-Boltzmann-Cluster for Cardiovascular Research, Vienna, Austria.
Department of Cardiothoracic Surgery, Medical University of Vienna, Vienna, Austria; Heartware Inc, Miami Lakes, Florida.
J Heart Lung Transplant. 2014 Apr;33(4):422-8. doi: 10.1016/j.healun.2013.10.032. Epub 2013 Oct 25.
Minimally invasive techniques are desirable to minimize surgical trauma during left ventricular assist device (LVAD) implantation. This is particularly challenging for full-flow support. In this study, a minimally invasive implantation technique was developed for a microaxial rotary pump. The system was evaluated in a chronic sheep model.
A HeartWare MVAD (HeartWare, Miami Lakes, FL) pump (length, 50 mm; diameter, 21 mm; maximum flow, 7-8 liters/min) was combined with a novel inflow cannula, including a new flow-optimized tip. The device was implanted into sheep (range, 60-80 kg, mean, 71.6 ± 6.8 kg) through a right-sided minithoracotomy. The inflow cannula was inserted through the superior pulmonary vein, passing through the left atrium into the left ventricle. Scheduled implant period was 30 days for 8 sheep and 100 days for 3 sheep. Mean support flow was set to half of the nominal cardiac output.
Six of 8 sheep finished the scheduled 30-day investigation period (one failed due to early non-pump-related post-operative bleeding and one due to prototype controller failure). The 3 sheep scheduled for 100 days reached the study end point. Peak pump flows of up to 6.9 liters/min were achieved. At necropsy, no signs of mitral valve lesions or thrombus formation around the cannula, the tip, or the insertion site were observed, except for valve leaflet erosion in 1 animal, where the cannula had been entangled in the sub-valvular chords due to lack of ultrasound monitoring.
The minimally invasive implantation technique using the HeartWare MVAD pump, together with a new cannula, provided excellent results in a chronic animal model.
微创技术是在植入左心室辅助装置（LVAD）时将手术创伤最小化的理想选择。对于全流量支持来说，这是特别具有挑战性的。在这项研究中，开发了一种用于微型轴流旋转泵的微创植入技术。该系统在慢性绵羊模型中进行了评估。
将 HeartWare MVAD（HeartWare，迈阿密湖，FL）泵（长度 50mm；直径 21mm；最大流量 7-8 升/分钟）与一种新型的流入管相结合，包括一种新的优化流量的尖端。该装置通过右侧小开胸术植入绵羊（范围 60-80kg，平均值 71.6±6.8kg）。流入管通过上肺静脉插入，穿过左心房进入左心室。计划的植入期为 8 只绵羊 30 天，3 只绵羊 100 天。平均支持流量设定为名义心输出量的一半。
8 只绵羊中有 6 只完成了计划的 30 天研究期（一只因早期与泵无关的术后出血失败，一只因原型控制器故障失败）。3 只计划进行 100 天的绵羊达到了研究终点。达到了高达 6.9 升/分钟的峰值泵流量。尸检时，除了 1 只动物因缺乏超声监测而导致瓣膜叶被卷入瓣下腱索，导致瓣膜叶侵蚀外，在流入管、尖端或插入部位周围未发现二尖瓣损伤或血栓形成的迹象。
使用 HeartWare MVAD 泵和一种新的导管的微创植入技术在慢性动物模型中提供了优异的结果。
