12th March 2024

Management

Native valve endocarditis is typically treated with antibiotic duration of 2-6 weeks. Prosthetic valve endocarditis requires treatment for longer than 6 weeks (see Table 1).

Table 1: Treatment and duration of antibiotics in IE. Adapted from 2015 ESC Guidelines for the management of infective endocarditis

Approximately half of patients with IE will eventually require surgery as a result of complications. Indications for cardiac surgery include:

• Heart Failure: aortic/mitral valve IE resulting in severe regurgitation with subsequent cardiogenic shock or pulmonary congestion. 
• Perivalvular extension: this can lead to formation of abscesses resulting in atrio-ventricular blocks and acute coronary syndromes.
• Resistant infection: fever and blood cultures remaining positive 7-10 days after antibiotic initiation
• Fungal aetiology: IE caused by these organisms have a low chance of being successfully treated with antibiotics alone
• Prevention of septic emboli: size of vegetations are associated with an increased risk of embolisation to the brain and lungs. Aortic or mitral vegetations >10mm on echocardiography are an indication for surgical escalation. 

As per the ESC 2018 update, antibiotic prophylaxis is currently recommended only for those patients with the highest risk of IE undergoing invasive dental operations. Those deemed to be at highest risk of I.E include one of three groups:

• Patients with a prosthetic valve or have had cardiac valve repair with prosthetic material
• Patients with previous IE
• Patients with untreated cyanotic heart disease

Antibiotics currently licensed for prophylaxis include either Amoxicillin or Ampicillin. Clindamycin can be used in cases of Penicillin allergy.