Freidoonimehr Navid, Girolamo Olivia, Atkins Tam, Yang Bo, Tavella Rosanna, Zeitz Christopher, Arjomandi Maziar, Beltrame John F
Advanced Cardiorespiratory Engineering Laboratory, School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, Queensland, Australia,
Centre for Biomedical Technologies, Queensland University of Technology, Brisbane, Queensland, Australia,
Cardiology. 2025 Jun 30:1-9. doi: 10.1159/000547197.
Intracoronary acetylcholine provocative testing is the gold standard method for the assessment of epicardial and/or microvascular spasm, with the latter diagnosed when there are acetylcholine (ACh)-induced chest pain and ischaemic electrocardiogram changes in the absence of epicardial spasm. While epicardial spasm can be visualised, microvascular spasm cannot and remains a presumed diagnosis.
This article describes a hydrodynamic model developed to calculate the epicardial and microvascular resistances for both pre- and post-ACh administration. The model is based on the concept of two resistances (epicardial and microvascular) located in a series arrangement. The epicardial resistance is obtained as a hydraulic resistance, accounting for the friction resistance between the coronary blood flow and the arterial walls. The microvascular resistance is calculated by subtracting the epicardial resistance from the ratio of the pressure and flow measured using coronary guidewire-based techniques.
This novel methodology provides key insights into the physiological characteristics of epicardial and microvascular spasm during ACh provocation testing. Further clinical validation is required to explore the clinical utility of this methodology.
冠状动脉内乙酰胆碱激发试验是评估心外膜和/或微血管痉挛的金标准方法，当在无心外膜痉挛的情况下出现乙酰胆碱（ACh）诱发的胸痛和缺血性心电图改变时，可诊断为微血管痉挛。虽然心外膜痉挛可以可视化，但微血管痉挛无法可视化，仍然是一种推测性诊断。
本文描述了一种流体动力学模型，该模型用于计算ACh给药前后的心外膜和微血管阻力。该模型基于串联排列的两个阻力（心外膜和微血管）的概念。心外膜阻力作为水力阻力获得，考虑了冠状动脉血流与动脉壁之间的摩擦阻力。微血管阻力通过使用基于冠状动脉导丝技术测量的压力与流量之比减去心外膜阻力来计算。
这种新方法为ACh激发试验中心外膜和微血管痉挛的生理特征提供了关键见解。需要进一步的临床验证来探索该方法的临床实用性。
