The left anterior descending (LAD) coronary artery is the most frequently involved vessel in coronary artery dissection, a cause of acute coronary syndrome or sudden cardiac death. The biomechanical mechanisms underlying arterial dissection are not well understood. This study investigated the dissection properties of LAD specimens harvested from explanted hearts at the time of cardiac transplantation, from patients with primary dilated cardiomyopathy (n = 12). Using a previously validated approach uniquely modified for these human LAD specimens, we quantified the local energy release rate, G, within different arterial layers during experimental dissection events (tissue tearing). Results show that the mean values of G during arterial dissection within the intima and within the media in human LADs are 20.7 ± 16.5 J/m2 and 10.3 ± 5.0 J/m2, respectively. The difference in dissection resistance between tearing events occurring within the intima and within the media is statistically significant. Our data fall in the same order of magnitude as most previous measurements of adhesive strength in other human arteries, with the differences in measured values of G within the layers most likely due to histologically observed differences in the structure and composition of arterial layers.

中文翻译：

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人冠状动脉内膜和中层剥离阻力的定量测量

左前降支 (LAD) 冠状动脉是冠状动脉夹层中最常受累的血管，是导致急性冠状动脉综合征或心源性猝死的原因。动脉夹层的生物力学机制尚不清楚。本研究调查了在心脏移植时从外植心脏采集的 LAD 标本的解剖特性，这些标本来自原发性扩张型心肌病患者（n = 12）。使用先前针对这些人类 LAD 标本进行独特修改的验证方法，我们量化了实验解剖事件（组织撕裂）期间不同动脉层内的局部能量释放率 G。结果表明，在人类 LAD 内膜内和中膜内动脉夹层期间 G 的平均值为 20.7 ± 16.5 J/m2 和 10.3 ± 5.0 J/m2，分别。在内膜和中膜内发生的撕裂事件之间的解剖阻力差异具有统计学意义。我们的数据与其他人类动脉中大多数先前的粘附强度测量值处于同一数量级，层内 G 测量值的差异很可能是由于组织学观察到的动脉层结构和组成的差异。