Infective Endocarditis

Which of the following organisms is the most common cause of infective endocarditis in India?

According to the modified Duke criteria, which of the following is classified as a major criterion for the diagnosis of infective endocarditis?

A 52-year-old man with a prosthetic aortic valve (mechanical, inserted 3 years ago for aortic stenosis) presents with fever, malaise, and new-onset heart failure. He has been compliant with anticoagulation (INR 2.5–3.5). On examination: temperature 39.2°C, new early diastolic murmur at the left sternal border, and signs of acute pulmonary edema. Blood cultures (before antibiotics) are pending. Transthoracic echocardiography is suboptimal due to acoustic shadowing from the prosthesis. Transesophageal echocardiography shows a 6 mm vegetation at the prosthetic valve-tissue interface with paravalvular aortic regurgitation. What is the most appropriate next step in management?

A 32-year-old man with a history of rheumatic mitral stenosis presents with fever, new cardiac murmur, and positive blood cultures growing Streptococcus viridans. Echocardiography confirms vegetations on the mitral valve. What is the drug of choice for this patient?

A 38-year-old man with a history of rheumatic mitral stenosis presents with fever, new cardiac murmur, and splinter hemorrhages on fingernails for 2 weeks. Blood cultures have been drawn. Which investigation is most specific for confirming the diagnosis of infective endocarditis?