Study on the blood flow in stenosed microvascular model under pulsed magnetic field

Abstract

It is widely known that abnormal peripheral blood circulation due to intravascular stenosis causes ischemic diseases and blood circulatory disorders. The purpose of this study was to investigate the influence of pulsed magnetic field (PMF) on hemodynamic characteristics in blood vessel with stenosis of 33% with diameter of 15μm, with the change of PMF intensity and hematocrit (Ht) concentration. Stenosed microvascular channels were fabricated using polydimethylsiloxane (PDMS). Our PMF stimulator has the maximum intensity of 2700G at a transition time of 102 μs with pulse intervals of 1Hz. For the Ht altered RBCs suspension, the changes in blood flow and deformation of red blood cells (RBCs) were examined before and after PMF stimulus with various intensity of 200∼2700G. In stenosed channel, threshold intensity for improvement of blood flow seems to be 400G. The higher the Ht, the higher the viscosity and the slower the velocity of RBCs, but after PMF stimulus, RBCs movement overall increased by more than 9∼67% in both Ht 5% and 20% RBCs suspension. Our study shows that PMF plays an important role in in treating cardiovascular diseases with blood circulation disorders caused by narrowing microvascular due to stenosis. In order to extend our results to clinical applications, we need develop more indicators for hemorheologic characteristics such as viscosity and resistance, and need further experiment with diverse PMF condition such as pulse shape, pulse duration, or repetition rate.