Coronary arteries are blood vessels that supply the heart muscle with oxygen-rich blood, running along its outer surface. Coronary artery disease (CAD) develops when these arteries become narrowed or blocked, commonly due to plaque buildup (atherosclerosis). While partial narrowing can cause symptoms such as chest pain (angina), a sudden and complete blockage can lead to a heart attack. Percutaneous Coronary Intervention (PCI) is a non-surgical procedure designed to open these narrowed or blocked coronary arteries. During PCI, a catheter is inserted into a peripheral blood vessel and guided to the affected coronary artery. The procedure typically involves using a balloon to widen the narrowed segment and often placing a small mesh tube, known as a stent, to maintain the artery's patency.