Wan Ab Naim Wan Naimah, Mohamed Mokhtarudin Mohd Jamil, Chan Bee Ting, Lim Einly, Ahmad Bakir Azam, Nik Mohamed Nik Abdullah
Faculty of Mechanical and Automotive Engineering Technology, University Malaysia Pahang, 26600 Pekan, Pahang, Malaysia.
Department of Mechanical Engineering, College of Engineering, University Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Kuantan, Pahang, Malaysia.
J Theor Biol. 2021 Jan 21;509:110527. doi: 10.1016/j.jtbi.2020.110527. Epub 2020 Oct 20.
Reperfusion of the blood flow to ischemic myocardium is the standard treatment for patients suffering myocardial infarction. However, the reperfusion itself can also induce myocardial injury, in which the actual mechanism and its risk factors remain unclear. This work aims to study the mechanism of ischemia-reperfusion treatment using a three-dimensional (3D) oxygen diffusion model. An electrical model is then coupled to an oxygen model to identify the possible region of myocardial damage. Our findings show that the value of oxygen exceeds its optimum (>1.0) at the ischemic area during early reperfusion period. This complication was exacerbated in a longer ischemic period. While a longer reperfusion time causes a continuous excessive oxygen supply to the ischemic area throughout the reperfusion time. This work also suggests the use of less than 0.8 of initial oxygen concentration in the reperfusion treatment to prevent undesired upsurge at the early reperfusion period and further myocardial injury. We also found the region at risk for myocardial injury is confined in the ischemic vicinity revealed by its electrical conductivity impairment. Although there is a risk that reperfusion leads to myocardial injury for excessive oxygen accumulation, the reperfusion treatment is helpful in reducing the infarct size.
恢复缺血心肌的血流灌注是心肌梗死患者的标准治疗方法。然而，再灌注本身也会诱发心肌损伤，其实际机制及其危险因素仍不清楚。这项工作旨在使用三维（3D）氧扩散模型研究缺血再灌注治疗的机制。然后将一个电学模型与一个氧模型耦合，以确定心肌损伤的可能区域。我们的研究结果表明，在再灌注早期，缺血区域的氧值超过其最佳值（>1.0）。在较长的缺血期，这种并发症会加剧。而较长的再灌注时间会导致在整个再灌注期间向缺血区域持续供应过多的氧。这项工作还建议在再灌注治疗中使用低于初始氧浓度0.8的值，以防止在再灌注早期出现不必要的氧激增和进一步的心肌损伤。我们还发现，心肌损伤风险区域局限于因电导率受损而显示的缺血附近区域。尽管再灌注因过多的氧积累而有导致心肌损伤的风险，但再灌注治疗有助于减小梗死面积。
