Which heart valve is most commonly affected by infective endocarditis?

Which heart valve is most commonly affected by infective endocarditis?

• A. Aortic valve
• B. Tricuspid valve
• C. Pulmonary valve
• D. Mitral valve

Answer: (D)

Infective endocarditis most often targets left-sided valves, and the mitral valve is the most commonly affected native valve. The left heart bears higher pressures and has more turbulent flow, which damages the endocardium and creates a nidus of platelet-fibrin that bacteria can latch onto to form vegetations. Preexisting mitral valve disease from rheumatic changes, degenerative wear, or calcification further predisposes the mitral valve to infection. While the aortic valve is also commonly involved, it ranks behind the mitral in frequency. In contrast, the tricuspid valve is more likely to be affected in intravenous drug users due to direct inoculation of pathogens into the venous system, and the pulmonary valve involvement is relatively rare.

Infective endocarditis most often targets left-sided valves, and the mitral valve is the most commonly affected native valve. The left heart bears higher pressures and has more turbulent flow, which damages the endocardium and creates a nidus of platelet-fibrin that bacteria can latch onto to form vegetations. Preexisting mitral valve disease from rheumatic changes, degenerative wear, or calcification further predisposes the mitral valve to infection. While the aortic valve is also commonly involved, it ranks behind the mitral in frequency. In contrast, the tricuspid valve is more likely to be affected in intravenous drug users due to direct inoculation of pathogens into the venous system, and the pulmonary valve involvement is relatively rare.