Lee Jack, Nordsletten David, Cookson Andrew, Rivolo Simone, Smith Nicolas
Department of Biomedical Engineering, King's College London, 3rd Floor, Lambeth Wing, St Thomas' Hospital, London, UK.
Biomech Model Mechanobiol. 2016 Dec;15(6):1535-1555. doi: 10.1007/s10237-016-0782-5. Epub 2016 Mar 23.
Coronary wave intensity analysis (cWIA) is a diagnostic technique based on invasive measurement of coronary pressure and velocity waveforms. The theory of WIA allows the forward- and backward-propagating coronary waves to be separated and attributed to their origin and timing, thus serving as a sensitive and specific cardiac functional indicator. In recent years, an increasing number of clinical studies have begun to establish associations between changes in specific waves and various diseases of myocardium and perfusion. These studies are, however, currently confined to a trial-and-error approach and are subject to technological limitations which may confound accurate interpretations. In this work, we have developed a biophysically based cardiac perfusion model which incorporates full ventricular-aortic-coronary coupling. This was achieved by integrating our previous work on one-dimensional modelling of vascular flow and poroelastic perfusion within an active myocardial mechanics framework. Extensive parameterisation was performed, yielding a close agreement with physiological levels of global coronary and myocardial function as well as experimentally observed cumulative wave intensity magnitudes. Results indicate a strong dependence of the backward suction wave on QRS duration and vascular resistance, the forward pushing wave on the rate of myocyte tension development, and the late forward pushing wave on the aortic valve dynamics. These findings are not only consistent with experimental observations, but offer a greater specificity to the wave-originating mechanisms, thus demonstrating the value of the integrated model as a tool for clinical investigation.
冠状动脉波强度分析（cWIA）是一种基于冠状动脉压力和速度波形侵入性测量的诊断技术。波强度分析理论能够分离向前和向后传播的冠状动脉波，并确定其起源和时间，从而成为一种敏感且特异的心脏功能指标。近年来，越来越多的临床研究开始探究特定波形变化与各种心肌和灌注疾病之间的关联。然而，这些研究目前局限于试错法，并且受到技术限制，可能会混淆准确的解释。在这项工作中，我们开发了一种基于生物物理学的心脏灌注模型，该模型纳入了完整的心室 - 主动脉 - 冠状动脉耦合。这是通过将我们之前关于血管流动和多孔弹性灌注的一维建模工作整合到一个主动心肌力学框架中实现的。进行了广泛的参数化，使得该模型与整体冠状动脉和心肌功能的生理水平以及实验观察到的累积波强度大小高度吻合。结果表明，反向抽吸波强烈依赖于QRS波持续时间和血管阻力，正向推动波依赖于心肌细胞张力发展速率，而晚期正向推动波依赖于主动脉瓣动力学。这些发现不仅与实验观察结果一致，而且为波的起源机制提供了更高的特异性，从而证明了该集成模型作为临床研究工具的价值。
