Research Project: Evaluation of Disturbed Flow Patterns through a Curved Stented Superficial Femoral Artery
3D Digital Particle Image Velocimetry (DPIV) In Vitro Evaluation of Disturbed Flow Patterns in a Curved Superficial Femoral Arterial (SFA) Stent Model: The use of implanted stents in coronary, peripheral vascular and carotid arteries has dramatically increased since the original approval by the FDA of the first coronary stent in 1994, largely as a result of technological advances. The prediction of stent implants by IData Research Inc. for the year 2009 is 567,000 units, and for the year 2011 it is predicted to approach 900,000 units.
Although existing stents perform their function of supporting diseased arterial tissue walls, stent design profoundly influences the post-procedural hemodynamic and solid mechanical environments of the stented artery. This alteration in the hemodynamic and mechanical environment of the stented artery is emerging as a critical factor in the long term patency of stented vessels. Both In vitro and In vivo studies have revealed that stent design and geometry influences local flow patterns and disturbances, thrombus accumulation between struts, and hence restenosis.
The ability to visually characterize 3D flow disturbances is critical to discern these geometry induced secondary and/or turbulent flow patterns, and the effects of stent design on the development of such non-laminar flow fields.
This proposed study will add 3D Digital Particle Image Velocimetry (DPIV) capability to our present 2D DPIV system, and permit us to characterize all three velocity components (u, v, and w), to more accurately quantify the velocity profiles and wall shear stresses that may contribute to red blood cell damage (hemolysis), or stagnant flow regions which may contribute to thrombus (blood clot) formation.
With the expected increase in stent submissions, and new expected bifurcated stent-graft devices coming on the market, new state of the art flow visualization techniques should be supported to keep up with future medical advancements, and help identify future problematic stent designs to insure more dependable vessel patency results.