What is the most common form of infective endocarditis?

What is the most common form of infective endocarditis?

• A. Prosthetic valve endocarditis
• B. Left-sided endocarditis
• C. Native valve endocarditis
• D. Right-sided endocarditis

Answer: (C)

Infective endocarditis most often involves a native valve rather than a prosthetic valve or the right-sided valves. Endothelial injury on native valves—especially the high‑pressure left‑sided valves like the mitral and aortic valves—promotes deposition of a platelet‑fibrin nidus that bacteria can adhere to, making native-valve endocarditis the commonest form. Prosthetic valve endocarditis happens, but it is less frequent than native-valve disease and has a different, more complex risk profile. Right-sided endocarditis occurs even less often overall and is more commonly seen with IV drug use or devices. So the typical pattern is infection on a native valve, which is why this is the most common form.

Infective endocarditis most often involves a native valve rather than a prosthetic valve or the right-sided valves. Endothelial injury on native valves—especially the high‑pressure left‑sided valves like the mitral and aortic valves—promotes deposition of a platelet‑fibrin nidus that bacteria can adhere to, making native-valve endocarditis the commonest form. Prosthetic valve endocarditis happens, but it is less frequent than native-valve disease and has a different, more complex risk profile. Right-sided endocarditis occurs even less often overall and is more commonly seen with IV drug use or devices. So the typical pattern is infection on a native valve, which is why this is the most common form.