Percutaneous Coronary Intervention (PCI) is a minimally invasive procedure used to treat narrowed or blocked coronary arteries, typically due to coronary artery disease. During PCI, a thin catheter with a balloon at the tip is inserted through a blood vessel in the arm or leg and guided to the affected artery. The balloon is inflated to widen the artery, improving blood flow to the heart. Often, a stent (a small mesh tube) is placed to keep the artery open. PCI is commonly referred to as angioplasty and helps relieve chest pain (angina) and reduce the risk of heart attacks.