Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, Medical Faculty, RWTH Aachen University, Aachen, Germany.
ReinHeart TAH GmbH, Aachen, Germany.
Artif Organs. 2022 Jan;46(1):71-82. doi: 10.1111/aor.14042. Epub 2021 Jul 30.
The objective of this study is to identify the preload and afterload sensitivity of the ReinHeart TAH 2.0. For adequate left-right flow balance, the concept of a reduced right stroke volume (by about 10%) and active adaption of the right diastole duration are evaluated concerning the controllability of the flow balance. This study used an active mock circulation loop to test a wide range of preload and afterload conditions. Preload sensitivity was tested at atrial pressures (APs) between 4 and 20 mm Hg. Left afterload was varied in a range of 60-140 mm Hg mean aortic pressure (MAP), right afterload was simulated between 15 and 40 mm Hg. Four scenarios were developed to verify that the flow difference fully covers the defined target range of 0-1.5 L/min. Although a positive correlation between inlet pressure and flow is identified for the right pump chamber, the left pump chamber already fills completely at an inlet pressure of 8-10 mm Hg. With increasing afterload, both the left and right flow decrease. A positive flow balance (left flow exceeds right flow) is achieved over the full range of tested afterloads. At high APs, the flow difference is limited to a maximum of 0.7 L/min. The controllability of flow balance was successfully evaluated in four scenarios, revealing that a positive flow difference can be achieved over the full range of MAPs. Under physiological test conditions, the linear relationship between flow and heart rate was confirmed, ensuring good controllability of the TAH.
本研究旨在确定 ReinHeart TAH 2.0 的前负荷和后负荷敏感性。为了实现左右心腔流量的平衡，评估了通过降低右心室每搏量（约 10%）和主动调整右心室舒张期持续时间的概念，以评估流量平衡的可控性。本研究使用主动模拟循环回路来测试广泛的前负荷和后负荷条件。在前负荷测试中，心房压（AP）在 4 至 20 毫米汞柱之间变化。左后负荷在 60-140 毫米汞柱平均主动脉压（MAP）范围内变化，右后负荷模拟在 15-40 毫米汞柱之间。开发了四个场景来验证流量差完全覆盖 0-1.5 升/分钟的定义目标范围。尽管右泵腔的入口压力与流量之间存在正相关关系，但入口压力为 8-10 毫米汞柱时，左泵腔已完全充满。随着后负荷的增加，左、右心腔的流量均下降。在整个测试后负荷范围内，实现了正流量平衡（左心腔流量超过右心腔流量）。在高心房压下，流量差限制在 0.7 升/分钟以内。在四个场景中成功评估了流量平衡的可控性，结果表明在整个 MAP 范围内都可以实现正流量差。在生理测试条件下，流量与心率之间的线性关系得到了确认，从而确保了 TAH 的良好可控性。
