Cardiovascular is a disorder of the heart and its blood vessels that causes millions of deaths around the world. Implanting stent in patient's artery is a typical procedure of treatment. However, a major problem associated with stents is the buildup of plaque/fatty acids deposits, a condition known as in-stent restenosis. Therefore, one of the preventive solutions is the development of "smart" stents that contain pressure sensors for monitoring stent blockage at early stages. Such sensors need to be associated with high sensitivity for early detection of flow abnormalities within the stent. Here, we propose several capacitive pressure sensor plate designs and analyze their sensitivities. Our results show that a square-shaped plate with straight slots on its edges can drastically improve sensitivity. Several analyses were carried out to optimize dimensions of the proposed design for monitoring in-stent restenosis.