Flow characteristics and wall shear stresses in bifurcated peripheral arteries

Abstract

Peripheral artery disease (PAD) is further complicated by co-morbidities like diabetes, hypertension and anemia. Previous studies on coronary and carotid arteries indicate that bifurcation at the arteries has an effect in the blood flow. When plaque develops at the bifurcation, it affects the velocity, blood pressure, shear stresses and flow rates of blood. Femoral artery flow is modeled with blockage at different bifurcation angles (30°,45° and 60°) and it is analyzed at different conditions. A review of stents shows that there are several limitations associated with stents in co-morbid PAD patients. A blocked bifurcated femoral artery is inserted with self expanding stent model and the blockage is modeled downstream of the stented region. Flow characteristics like velocity and wall shear stress in stented and blocked femoral artery are compared with plane artery (no stenosis) to study the effect of stent placements. Postural positions are found to affect the systolic and diastolic blood pressures in an artery. The study shows velocities and wall shear stresses in anterior and posterior tibial artery at different bifurcation angles and postures, and determined specific postures affect diabetic patients in different ways. Existing in-vitro studies indicate that plaque most commonly develops downstream of the knee region such as in a popliteal artery. Popliteal artery is modeled at various lower extremity angles and analyzed at varying co-morbidities. The analysis shows a highly affected bifurcation angle in a diseased artery, posture and knee curvature affects peripheral arteries to worse. The wall shear stress values from the analysis may be used for developing therapeutic drugs using nano particles.