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Coronary artery disease (CAD)develops when the major blood vessels that supply blood to the heart muscles become damaged or diseased. CAD occurs when the coronary arteries become narrowed or blocked because of the build- up of fat, cholesterol, and other substances within the artery wall. Using computational methods can help visualize blood flow in the coronary artery bifurcation and with the study of certain hemodynamic parameters, the occurrence of Atherosclerosis can be predicted to a certain extent. The paper mainly focuses on using two-way Fluid Structure Interaction (FSI) to simulate and study the relation between stenosis location and percentage of blockage with parameters such as Wall Shear Stress (WSS) and velocity. It was observed that Wall Shear stress increases almost linearly with increase in velocity and it was also seen that proximity of stenosis at bifurcation resulted in higher oscillatory nature of WSS

Coronary stents are tubular, mesh-like structures used to force open clogged artery. Mounted on an inflatable balloon, stent compresses calcified plaque inside atherosclerotic artery with an inflating device, which transfers the load through the compliant balloon, thus maintaining the patency of lumen. One of the contributors for success of angioplasty is type of stents, which mainly differs in its geometrical design. A clinician recommends a stent based on comparative advantages. An ideal stent should be flexible to manoeuver through tortuous artery, easy to expand, provide good scaffolding to the vessel, have less radial recoil and foreshortening, possess uniformity in expansion and induce minimum alteration in physiological blood flow dynamics. In a stent these parameters are in competition with each other and are optimized by trade-offs. The present work tries to sequentially investigate the effect of number of stent cells and type of links on the expansion and haemodynamics behaviour through computational analysis based on finite element and finite volume techniques. The study compares performance within same classes of designs rather than comparing the designs that are completely different form each other. Results show that more number of stent cells in longitudinal direction considerably decrease the radial recoil, but increase the foreshortening effect. Restenosis-prone zones are localized around the stent struts and are predominant during end of systolic phase of cardiac cycle. Shorter links are preferred for better recoil and favourable distribution of wall shear stress while longer links are preferred for favourable foreshortening.

Numerical analysis of complex physical environment continues to be preferred over “build and test” approach in product development process. Finite Element Analysis (FEA) of coronary artery stenting is studied and researched worldwide for many years. Potential of using FEA for mimicking in-vivo is high as experimental test is ruled out for variety of reasons. This review aims at discussing issues and challenges of numerical simulation based on part of available literature on usage of FEA techniques for investigating behavior of balloon expandable (BE) coronary stents inside artery. Literatures of past 16 years of study on the structural analysis is summarized and potential issues for research is discussed. Study tries to investigate deployment characteristics and biomechanical response of artery post stenting and significance of non-physiological conditions induced. Effects of geometrical parameters, simulation strategies are summarized. Study mainly underscores the potential challenges of reliable numerical investigation. Scope of FEA in predicting contributor for in-stent restenosis (ISR), a major drawback of stenting procedure, by correlating the engineering aspect of stent design and its clinical significance supported by clinical trials are highlighted. Study is expected to serve as qualitative assessment for cardiologists to minimize procedural failure and quantitative tool for the designers for stent optimization.