Causes and Risk Factors of Endocarditis

Endocarditis, particularly infective endocarditis, typically develops in individuals with underlying heart conditions. Common predisposing factors include pre-existing heart diseases such as mitral valve disorders or congenital heart defects like atrial septal defect, ventricular septal defect, and patent ductus arteriosus. These conditions create an environment where bacteria can more easily attach and grow on the inner lining of the heart or heart valves.

How Infection Occurs

Patients who have undergone heart valve surgery or have structural heart abnormalities are especially vulnerable. When an infection is present elsewhere in the body—especially one that enters the bloodstream—bacteria can travel to the heart. Once in the bloodstream, these pathogens can settle on the heart valves or endocardium, particularly in areas already damaged or altered by disease.

The Development of Infective Endocarditis

Once bacteria colonize the heart tissue, they begin to multiply and attract deposits of fibrin and platelets. This process leads to the formation of vegetations—clumps of bacteria, blood cells, and fibrin—on the heart valves. These vegetations are unstable and can break off, traveling through the bloodstream to other organs, potentially causing secondary infections in distant parts of the body.

Sources of Bacterial Infection

Common sources of infection include untreated fungal infections like athlete's foot or bacterial infections resulting from dental procedures such as tooth extraction. These infections can enter the bloodstream, leading to bacteremia. Individuals with existing heart conditions who develop persistent or recurring fever should be evaluated for possible infective endocarditis.

Diagnosis and Delayed Detection

In some cases, the cause of symptoms remains undiagnosed for weeks or even months. Eventually, imaging techniques such as echocardiography may reveal new growths on the heart valves or endocardium, confirming the diagnosis of infective endocarditis. Early detection is crucial due to the serious nature of this condition.

Treatment Challenges

Infective endocarditis poses significant health risks. While long-term antibiotic therapy is the primary treatment, not all cases respond adequately. In such instances, surgical intervention may be necessary to repair or replace damaged heart valves and eliminate the infection completely.