What are the indications for surgical treatment of endocarditis?

Among patients with endocarditis, 40 - 45% will need surgical intervention.  The rest will get better on a prolonged antibiotics alone.  Indications for surgical treatment are:

• severe valvular dysfunction likely to precipitate hemodynamic compromise, ie. CHF
• intracardiac abscess
• endocarditis caused by organisms known to be refractory to medical management including Pseudomonas, Candida, and multidrug-resistant organisms

Source

McDonald, J.  "Acute Infective Endocarditis"  Infect Dis Clin N Am.  2009.