de Vos Annemiek, Troost Sophie, Waterschoot Anke, Pijls Nico, van 't Veer Marcel
Department of Cardiology, Catharina Hospital, Eindhoven, The Netherlands.
Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
Eur Heart J Digit Health. 2024 May 16;5(4):491-501. doi: 10.1093/ehjdh/ztae033. eCollection 2024 Jul.
Continuous infusion thermodilution is an established technique for the assessment of absolute coronary blood flow and microvascular resistance due to its proven accuracy and reproducibility. However, for this technique to yield reliable measurements, direct and homogenous mixing of injected saline and blood is mandatory. This study aimed to assess and compare the mixing properties of two different microcatheters, namely the Rayflow® (with sideholes for infusion) and the Finecross® catheter (single end-hole for infusion), which are commonly used in the catheterization laboratory.
The study employed three different methods to evaluate the mixing properties of the catheters. Firstly, a qualitative assessment of mixing was performed using ink injections in an bench model of a coronary artery. Secondly, in analogy to the human catheterization laboratory, mixing properties over the length of the coronary artery were assessed semi-quantitatively by temperature measurements in the bench model. Lastly, a quantitative assessment was performed by 3D computational fluid dynamics, where the standard deviation and entropy ratio of the temperature over the cross-section in the coronary artery model were calculated for both catheters.
All three evaluation methods demonstrated that the Rayflow catheter's specific design leads to a more optimal, homogeneous mixture of blood and saline over both the cross-section and length of a coronary vessel, as compared with the standard end-hole catheter.
连续输注热稀释法是一种成熟的技术，因其已被证实的准确性和可重复性，可用于评估绝对冠状动脉血流量和微血管阻力。然而，要使该技术获得可靠的测量结果，注入的盐水和血液必须直接且均匀地混合。本研究旨在评估和比较两种不同的微导管（即Rayflow®导管（带有用于输注的侧孔）和Finecross®导管（用于输注的单端孔））的混合特性，这两种导管常用于导管实验室。
本研究采用三种不同方法评估导管的混合特性。首先，在冠状动脉的实验台模型中通过注入墨水对混合进行定性评估。其次，类似于人体导管实验室，通过在实验台模型中进行温度测量，对冠状动脉长度上的混合特性进行半定量评估。最后，通过三维计算流体动力学进行定量评估，计算两种导管在冠状动脉模型横截面上温度的标准差和熵比。
所有三种评估方法均表明，与标准端孔导管相比，Rayflow导管的特殊设计可在冠状动脉的横截面和长度上实现血液与盐水更优化、更均匀的混合。
