Georgia Institute of Technology, G.W. Woodruff School of Mechanical Engineering, 315 Ferst Drive NW, IBB 2307, Atlanta, GA, 30332, USA.
Sci Rep. 2024 May 20;14(1):11460. doi: 10.1038/s41598-024-62165-1.
Arterial occlusion by thrombosis is the immediate cause of some strokes, heart attacks, and peripheral artery disease. Most prior studies assume that coagulation creates the thrombus. However, a contradiction arises as whole blood (WB) clots from coagulation are too weak to stop arterial blood pressures (> 150 mmHg). We measure the material mechanical properties of elasticity and ultimate strength for Shear-Induced Platelet Aggregation (SIPA) type clots, that form under stenotic arterial hemodynamics in comparison with coagulation clots. The ultimate strength of SIPA clots averaged 4.6 ± 1.3 kPa, while WB coagulation clots had a strength of 0.63 ± 0.3 kPa (p < 0.05). The elastic modulus of SIPA clots was 3.8 ± 1.5 kPa at 1 Hz and 0.5 mm displacement, or 2.8 times higher than WB coagulation clots (1.3 ± 1.2 kPa, p < 0.0001). This study shows that the SIPA thrombi, formed quickly under high shear hemodynamics, is seven-fold stronger and three-fold stiffer compared to WB coagulation clots. A force balance calculation shows a SIPA clot has the strength to resist arterial pressure with a short length of less than 2 mm, consistent with coronary pathology.
血栓引起的动脉阻塞是一些中风、心脏病发作和外周动脉疾病的直接原因。大多数先前的研究假设凝血会形成血栓。然而，由于全血（WB）凝结形成的血栓太弱，无法阻止动脉血压（>150mmHg），这就出现了矛盾。我们测量了剪切诱导血小板聚集（SIPA）型血栓的弹性和极限强度等物质力学性能，这些血栓是在狭窄动脉血流动力学条件下形成的，与凝血血栓形成进行了比较。SIPA 血栓的极限强度平均为 4.6±1.3kPa，而 WB 凝血血栓的强度为 0.63±0.3kPa（p<0.05）。SIPA 血栓在 1Hz 和 0.5mm 位移下的弹性模量为 3.8±1.5kPa，是 WB 凝血血栓（1.3±1.2kPa）的 2.8 倍（p<0.0001）。这项研究表明，在高剪切血流动力学条件下迅速形成的 SIPA 血栓，其强度比 WB 凝血血栓高 7 倍，硬度高 3 倍。力平衡计算表明，SIPA 血栓具有抵抗动脉血压的强度，其长度短于 2mm，与冠状动脉病理学一致。
