School of Biomedical Engineering and Imaging Sciences, King's College London, Becket House, 1 Lambeth Palace Road, SE1 7EU, London, UK.
Cardiology Department, Guy's and St, Thomas's Hospital, London, UK.
J Cardiovasc Transl Res. 2023 Aug;16(4):862-873. doi: 10.1007/s12265-022-10350-w. Epub 2023 Feb 6.
Aortic stenosis is a condition which is fatal if left untreated. Novel quantitative imaging techniques which better characterise transvalvular pressure drops are being developed but require refinement and validation. A customisable and cost-effective workbench valve phantom circuit capable of replicating valve mechanics and pathology was created. The reproducibility and relationship of differing haemodynamic metrics were assessed from ground truth pressure data alongside imaging compatibility. The phantom met the requirements to capture ground truth pressure data alongside ultrasound and magnetic resonance image compatibility. The reproducibility was successfully tested. The robustness of three different pressure drop metrics was assessed: whilst the peak and net pressure drops provide a robust assessment of the stenotic burden in our phantom, the peak-to-peak pressure drop is a metric that is confounded by non-valvular factors such as wave reflection. The peak-to-peak pressure drop is a metric that should be reconsidered in clinical practice. The left panel shows manufacture of low cost, functional valves. The central section demonstrates circuit layout, representative MRI and US images alongside gross valve morphologies. The right panel shows the different pressure drop metrics that were assessed for reproducibility.
主动脉瓣狭窄是一种如果不治疗就会致命的疾病。目前正在开发新的定量成像技术，以更好地描述跨瓣压差，但这些技术需要进一步改进和验证。我们创建了一个定制的、具有成本效益的瓣膜模型工作坊，该模型能够复制瓣膜的力学和病理学特性。通过真实压力数据和成像兼容性评估了不同血流动力学指标的可重复性和相关性。该模型满足了捕获真实压力数据以及与超声和磁共振成像兼容性的要求。我们成功地测试了模型的可重复性。评估了三种不同的压力降指标的稳健性：虽然峰值和净压力降为我们的模型中的狭窄负担提供了稳健的评估，但峰峰值压力降是一个受到瓣膜以外因素（如波反射）影响的指标。在临床实践中，应该重新考虑峰峰值压力降这个指标。左侧面板显示了低成本、功能性瓣膜的制造过程。中间部分展示了电路布局、代表性的 MRI 和 US 图像以及大体瓣膜形态。右侧面板显示了为评估可重复性而评估的不同压力降指标。
