Coronary artery disease is characterized by the deposition of plaque consisting of substances such as fatty acids and proteins on the inner lining of the arteries. With the presence of plaque in coronary arteries, the blood flow is obstructed, affecting the blood supply to the heart. In this work, we have constructed patient-specific models of coronary arteries from computed tomography angiography (CTA) images. Computational fluid dynamics (CFD) simulations have been performed for both a healthy and a stenosed left anterior descending artery. A comparative analysis between the two states reveals how the flow redistribution in the left coronary branch happens in the presence of plaque. The qualitative and quantitative evaluation of the hemodynamic biomarkers was performed. Post-stenotic region was found to have lower value of wall shear stress and higher value of oscillatory shear index (OSI) and relative residence time (RRT) and can be considered as a potential risk for worsening the atherosclerosis.