Infective endocarditis is an inflammatory infection of the lining of the heart valves and chambers. This disease causes bacteria (vegetations) to grow on the valves where they produce toxins and enzymes that are capable of breaking down heart tissue. If left untreated, the damage to the heart valves could be permanent which could eventually lead to heart failure, thrombus formation, or even death.

Bacterial endocarditis is another name for this disease since bacteria are the most common agents but fungi and other germs can also cause endocarditis. These pathogens enter the bloodstream and attach themselves to damaged structures in the heart where they can multiply and cause greater problems in the circulatory system. The following are risk factors that increase the chances of a an individual developing infective endocarditis:

• Structural heart diseases
• Abnormal heart valves
• Prosthetic heart valves
• Pacemaker implants
• Rheumatic fever and rheumatic heart disease

Infective endocarditis can present acutely (rapid progression) or subacutely (developed over time) and the most common symptoms that manifest are listed below:

• Fever
• Fatigue and shortness of breath upon exertion
• New heart murmur
• Night sweats
• Swelling in the feet or legs
• Chest pain when breathing
• Rapid heart rate
• Small red spots in the eye conjunctiva and fingernails
• Janeway lesions on the palms and soles

Diagnosing endocarditis is based upon history, physical examination, and some laboratory tests. The disease of the patient must satisfy certain findings under the modified Duke criteria to be diagnosed as definite infective endocarditis. 

Blood cultures are key to determining the main agent of the infection so proper antibiotics can be prescribed by the physician. The antibiotics are then delivered through IV for the first few weeks depending on the bacterium responsible for the disease. Echocardiography is also done to observe heart valve involvement and decide whether heart failure medications or surgical repair is required.

Patients who have recovered from this disease are at a greater risk of recurrent infective endocarditis. These patients should be educated about the possibility of relapse, what symptoms to look out for, and where to find immediate medical care once these symptoms do appear. Doctors can give antibiotic prophylaxis to patients with the highest risk to help ensure that endocarditis does not develop again. 

References:

Chu, V., & Sexton, D. (2022). Prevention of endocarditis: Antibiotic prophylaxis and other measures. https://www.uptodate.com/contents/prevention-of-endocarditis-antibiotic-prophylaxis-and-other-measures

Chu, V., & Wang, A. (2022). Clinical manifestations and evaluation of adults with suspected left-sided native valve endocarditis. https://www.uptodate.com/contents/clinical-manifestations-and-evaluation-of-adults-with-suspected-left-sided-native-valve-endocarditis

O’Brein, S. (2022). Infective endocarditis in children. UpToDate. https://www.uptodate.com/contents/infective-endocarditis-in-children