Endocarditis is a medical term that refers to an inflammation of the inner lining of the heart (endocardium). It is typically caused by a bacterial infection that spreads to the heart from other parts of the body. 

Key points about endocarditis:

• Inflammation of the endocardium
• Caused by bacterial infection
• Affects the inner lining of the heart chambers and valves
• Can lead to serious complications, such as heart valve damage and heart failure
• Symptoms may include fever, chills, fatigue, and joint pain
• Treatment usually involves antibiotics and may require surgery in some cases