What is the management plan for an adult patient with a history of infective endocarditis of the aortic valve, now presenting with worsening moderate to severe aortic regurgitation (AR), fatigue, night sweats, and dyspnea on exertion?

Management of Recurrent Infective Endocarditis with Worsening Aortic Regurgitation

This patient requires urgent hospitalization, immediate blood cultures, empirical antibiotic therapy, and urgent cardiac surgery consultation with strong consideration for early surgical intervention given the combination of moderate-to-severe AR, symptoms, and suspected active endocarditis. 1

Immediate Diagnostic Workup

• Obtain at least 3 sets of blood cultures from separate venipuncture sites before initiating antibiotics to identify the causative organism and guide targeted therapy 1
• Perform urgent transthoracic echocardiography (TTE) followed by transesophageal echocardiography (TEE) to assess vegetation size, valve destruction, perivalvular extension (abscess formation), and quantify AR severity 1
• Obtain baseline ECG to evaluate for heart block, which may indicate perivalvular abscess extension 1
• Assess left ventricular function and dimensions, as LV systolic dysfunction or progressive LV enlargement are surgical indications even in the absence of active infection 1

Critical pitfall: The presence of night sweats, fatigue, and worsening AR in a patient with previous IE strongly suggests recurrent/relapsed endocarditis rather than simple hemodynamic progression. Do not delay blood cultures or empirical antibiotics while awaiting echocardiography if the patient is hemodynamically unstable 1

Empirical Antibiotic Therapy

Initiate broad-spectrum antibiotics immediately after blood cultures are obtained 1:

• For subacute presentation (weeks) of native valve endocarditis, provide coverage for S. aureus, viridans group streptococci (VGS), HACEK organisms, and enterococci 1
• A reasonable empirical regimen includes vancomycin plus gentamicin plus either ampicillin or ceftriaxone to cover the most likely pathogens 1
• Consult infectious diseases immediately to optimize antimicrobial selection, as this is a Class I recommendation for culture-negative or complicated endocarditis 1
• Once blood cultures identify the pathogen, narrow therapy to pathogen-directed treatment 1

Surgical Indications and Timing

This patient has multiple Class I indications for urgent cardiac surgery 1:

1. Heart failure due to severe AR - The patient has dyspnea on exertion and moderate-to-severe AR, which constitutes valve regurgitation resulting in heart failure 1
2. Hemodynamic evidence of elevated LV filling pressures - Dyspnea on exertion with moderate-to-severe AR indicates elevated left atrial/LV end-diastolic pressures 1
3. Active endocarditis with worsening valve function - The combination of constitutional symptoms (night sweats, fatigue) and progressive AR suggests active infection with ongoing valve destruction 1, 2

Timing of Surgery

• Surgery should not be delayed when heart failure is present in acute infective endocarditis 1
• The presence of symptoms (dyspnea, fatigue) with moderate-to-severe AR indicates the patient is already decompensating and requires urgent intervention 1, 3
• Historical data demonstrates that immediate surgery (within 24 hours) for severe AR with NYHA Class IV symptoms and active IE has acceptable mortality (6-7%) and prevents further deterioration 3
• Waiting for completion of antibiotic therapy is not necessary when heart failure or hemodynamic instability is present 1, 3

Additional surgical indications to assess:

• Perivalvular abscess formation (evaluate with TEE) - Class I indication for surgery 1
• Vegetation size >10mm, particularly with embolic events - increases embolic risk and may warrant earlier surgery 1
• Persistent bacteremia despite appropriate antibiotics (repeat blood cultures at 48-72 hours) 1
• Heart block on ECG suggesting perivalvular extension 1

Perioperative Management

• Discontinue warfarin if the patient is anticoagulated and transition to heparin to allow for urgent surgery without delay for warfarin reversal 1
• Discontinue aspirin to reduce bleeding risk 1
• If neurological symptoms develop, hold anticoagulation until intracranial hemorrhage is excluded by imaging 1
• Intra-aortic balloon pump is absolutely contraindicated in severe AR as it worsens regurgitant volume 4
• Temporary medical stabilization may include vasodilators (nitroprusside) and inotropes to augment forward flow, but surgery must not be delayed 4

Surgical Approach

• Aortic valve replacement is the standard procedure for IE with severe AR 1, 2
• Mechanical prosthesis is most commonly used (83% in one series), though choice depends on patient age, anticoagulation tolerance, and surgeon preference 2
• Assess for mitral valve involvement intraoperatively, as combined aortic and mitral valve replacement may be necessary 3
• Complete debridement of infected tissue and abscess drainage if present 1

Postoperative Antibiotic Duration

• Continue pathogen-directed antibiotics for 4-6 weeks postoperatively from the date of surgery 3
• The surgical procedure does not "reset" the antibiotic clock - total duration should be adequate to eradicate infection 1

Critical Contraindications to Delaying Surgery

Do not wait for antibiotic completion if any of the following are present 1, 3, 5:

• Progressive heart failure or hemodynamic instability
• Cardiogenic shock
• Evidence of perivalvular extension (abscess, fistula, heart block)
• Persistent bacteremia despite appropriate antibiotics
• Recurrent embolic events

The mortality for severe AR with active IE and advanced heart failure is 15-28% even with surgery 5, and procrastination increases morbidity and mortality 3. Early surgical intervention in the active phase of endocarditis provides good short and mid-term outcomes 2.