Endocarditis is an inflammation of your heart's inner lining. The most common type, bacterial endocarditis, occurs when germs enter your heart. These germs come through your bloodstream from another part of your body, often your mouth. Bacterial endocarditis can damage your heart valves. If untreated, it can be life-threatening. It is rare in healthy hearts. Risk factors include having An abnormal or damaged heart valve A severe case of mitral valve prolapse An artificial heart valve Certain heart defects If you have a high risk of bacterial endocarditis, your doctor might prescribe antibiotics before dental work and certain types of surgery. Early treatment can help you avoid complications. Symptoms you might notice include fever, shortness of breath, fluid buildup in your arms or legs, tiny red spots on your skin and weight loss. Treatment usually involves high-dose antibiotics.