American Board of Internal Medicine (ABIM) Certification Practice Exam

When should patients with left-sided endocarditis from Staphylococcus aureus undergo surgery?

1. Only after antibiotic therapy for 7 days

2. With persistent bacteremia and heart failure symptoms

3. When diagnosed with a mild bacterial infection

4. After 4 weeks of intravenous antibiotics

The correct answer is: With persistent bacteremia and heart failure symptoms

Patients with left-sided endocarditis caused by Staphylococcus aureus should undergo surgery when there is persistent bacteremia accompanied by heart failure symptoms. This recommendation is based on the aggressive nature of Staphylococcus aureus infections, which can quickly lead to severe complications, including the development of heart failure. Persistent bacteremia indicates that the infection is not resolving with medical therapy and poses a significant risk for further embolic events and deterioration of cardiac function. Additionally, the presence of heart failure symptoms suggests that the structural integrity of the heart is compromised, which may require surgical intervention to address the infected valve and prevent further complications. This surgical approach is often necessary when medical management alone is insufficient to control the infection or provide symptomatic relief in critically ill patients. Surgical intervention early in the course of illness, particularly when there are signs of systemic instability or heart failure, helps improve prognosis and may reduce mortality associated with these severe infections.