Pericardial effusion is a medical condition where excess fluid accumulates in the pericardial sac, the double-layered membrane surrounding the heart. This fluid buildup can occur due to various reasons, including infections, inflammation, or injury. When the fluid volume increases significantly, it can put pressure on the heart, affecting its ability to pump blood effectively. Symptoms of pericardial effusion may include chest pain, shortness of breath, and a feeling of fullness in the chest. Diagnosis is typically made through imaging tests like ultrasound or CT scans. Treatment options vary depending on the severity and underlying cause, ranging from monitoring to procedures that drain the excess fluid.