The Intervention Centre, Division of Technology and Innovation, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
The Intervention Centre, Division of Technology and Innovation, Oslo University Hospital, Oslo, Norway.
J Heart Lung Transplant. 2024 Jan;43(1):111-119. doi: 10.1016/j.healun.2023.08.022. Epub 2023 Sep 4.
Pump thrombosis (PT) and related adverse complications contributed to the HeartWare Ventricular Assist Device (HVAD) market withdrawal. Many patients still receive lifelong support, with deficient PT surveillance based on pump power trends. Analysis of pump vibrations is better for detecting PT. Here, we investigated the feasibility of an extracorporeal accelerometer to detect PT from pump vibrations propagated out on the driveline.
In a porcine HVAD model (n = 6), an accelerometer was attached to the pump as a reference and another to the driveline for comparisons of signals. In total, 59 thrombi were injected into the heart to induce PT, followed by intermittent thrombus washout maneuvers. Signals were compared visually in spectrograms and quantitatively in third harmonic saliences (S) by correlation analysis. Receiver operating characteristic curves expressed the method's outcome in sensitivity vs specificity, with the overall diagnostic performance in the area under the curve (AUC) score.
Five experiments had good driveline signal strength, with clear spectrographic relationships between the 2 accelerometers. Third harmonic driveline vibrations were visible 20 vs 30 times in the reference. The comparison in S showed a strong correlation and yielded an AUC of 0.85. Notably, S proved robust regarding noise and false PT detections.
An extracorporeal accelerometer on the driveline can be a readily available method for accurate HVAD PT detection before an accelerometer integration with left ventricular assist device is feasible.
泵血栓（PT）和相关的不良并发症导致 HeartWare 心室辅助装置（HVAD）市场退出。许多患者仍需接受终身支持，但基于泵功率趋势的 PT 监测不足。分析泵振动更有助于检测 PT。在这里，我们研究了从泵振动通过驱动轴传播到体外的加速度计检测 PT 的可行性。
在猪的 HVAD 模型中（n=6），将加速度计附着在泵上作为参考，另一个附着在驱动轴上进行比较。总共将 59 个血栓注入心脏以诱导 PT，然后进行间歇性血栓冲洗操作。通过相关分析，在频谱图中进行视觉比较，并在第三谐波显着性（S）中进行定量比较。接收器操作特征曲线表示方法的敏感性与特异性的结果，总体诊断性能用曲线下面积（AUC）评分表示。
五个实验的驱动轴信号强度良好，两个加速度计之间的频谱关系清晰。第三谐波驱动轴振动在参考中可见 20 次，而在参考中可见 30 次。S 的比较显示出很强的相关性，AUC 为 0.85。值得注意的是，S 在噪声和假 PT 检测方面表现稳健。
在可将加速度计与左心室辅助装置集成之前，驱动轴上的体外加速度计可以成为一种准确检测 HVAD PT 的简便方法。
