Casikar Vidyasagar, Ramaswamy G S, Vidyasagar Vyshnavi
Nepean Hospital, P. O. Box. 63, Kingswood, NSW, 2751, Australia.
Cardiovasc Eng. 2010 Jun;10(2):66-77. doi: 10.1007/s10558-010-9095-y.
Hemodynamic play a very significant role in the pathophysiology of intracranial arteriovenous malformation. The surgical decisions are based on the understanding of the complexities of the flow. Quantification of the abnormal flow is difficult. The mathematical models provide limited information due to the simplicity of the design of these models. Flow of fluid in a tube is very sensitive to small changes in the diameter. We studied the flow characteristics of a fistula by introducing accurately machined acrylic fistulae between the femoral arteries and veins of dogs. The influences of systemic arterial pressure, diameter of the arterial feeders, volume of blood flow, velocity of flow and the diameter of the shunt on the flow of blood across the shunt were studied. Our experiments suggest that the flow characteristics of an arteriovenous fistulae are complex and are influenced by small changes in the diameters of the fistula and the feeding artery. Our model demonstrates the occurrence of the anomalous flow reduction in the fistula and steal phenomenon and is therefore a more realistic representation of the clinical situation. The design of a mathematical model should include the diameter of the fistula if it is intended to replicate the hemodynamic characteristics of an arteriovenous malformation more faithfully.
血流动力学在颅内动静脉畸形的病理生理学中起着非常重要的作用。手术决策基于对血流复杂性的理解。异常血流的量化很困难。由于这些模型设计简单，数学模型提供的信息有限。管内流体的流动对直径的微小变化非常敏感。我们通过在狗的股动脉和静脉之间引入精确加工的丙烯酸瘘管来研究瘘管的血流特性。研究了全身动脉压、动脉供血支直径、血流量、流速和分流直径对分流处血流的影响。我们的实验表明，动静脉瘘的血流特性很复杂，并且受到瘘管和供血动脉直径微小变化的影响。我们的模型证明了瘘管中异常血流减少和盗血现象的发生，因此更真实地反映了临床情况。如果要更忠实地复制动静脉畸形的血流动力学特征，数学模型的设计应包括瘘管的直径。
