Cardiothoracic Surgery: Infective Endocarditis

Infective Endocarditis

Risk Factors

  • Structural Heart Disease
    • Valvular Disease (Mitral Valve Prolapse, Mitral Regurgitation, Aortic Stenosis, Aortic Regurgitation, Rheumatic Heart Disease)
    • Congenital Heart Disease (Bicuspid Valve Disease, Ventricular Septal Defect, Patent Ductus Arteriosus, Tetralogy of Fallot)
  • Prosthetic Heart Valve
  • Age > 60 Years
  • Male Sex
  • IV Drug Abuse
  • Poor Dentition
  • Cardiac Implantable Electronic Device
  • Hemodialysis

Site

  • Side:
    • Most Common Side Overall: Left Side
    • Most Common Side in Drug Abuse: Right Side
  • Valve:
    • Most Common Native Valve: Mitral Valve
    • Most Common Prosthetic Valve: Aortic Valve

Microbiology

  • Staphylococcus aureus – Most Common Organism
  • Viridans Group Streptococci
  • Enterococci
  • Coagulase Negative Staphylococcus
  • Streptococcus bovis – Associated with Ulcerative Lesions of the Colon (Malignancy or Ulcerative Colitis)
  • HACEK Group: Hemophilus, Aggregatibacter, Cardiobacterium, Eikenella & Kingella

Presentation

  • Fever
  • Anorexia
  • Weight Loss
  • Malaise
  • Signs:
    • Petechiae on Skin or Mucous Membranes
    • Splenomegaly
    • Clubbing of the Digits
    • Splinter Hemorrhages – Linear Red-Brown Lesions Under the Nail Bed
    • Janeway Lesions – Nontender Erythematous Macules on the Palms & Soles
    • Osler Nodes – Tender Subcutaneous Nodules on the Pads of the Fingers & Toes
    • Roth Spots – Exudative, Erythematous Hemorrhagic Lesions of the Retina with Pale Centers
  • Complications:
    • Heart Failure
    • Valvular Insufficiency
    • Embolic Stroke
    • Brain Abscess
    • Septic Emboli
    • Metastatic Abscesses

Diagnosis

Diagnosis

  • General Evaluation:
    • Labs:
      • Leukocytosis
      • Bacteremia on Blood Cultures
    • Imaging: Echocardiogram
    • All Require a Thorough Dental Examination
  • Diagnosis: “Duke Criteria”
    • Pathologic Lesions: Histologic Evidence of Endocarditis
    • Microorganisms: Culture of a Vegetation or Intracardiac Abscess
    • Clinical Criteria:
      • 2 Major Criteria
      • 1 Major Criteria & 3 Minor Criteria
      • 5 Minor Criteria

Major Criteria

  • Positive Blood Cultures:
    • Typical Microorganism for Infective Endocarditis from Two Separate Blood Cultures
    • Persistently Positive Blood Cultures:
      • ≥ 2 Blood Cultures Drawn > 12 Hours Apart
      • All of 3 or The Majority of 4 Blood Cultures with the First & Last Drawn ≥ 1 Hour Apart
    • Single Positive Blood Culture forCoxiella burnetii or Phase I IgG Antibody Titer to Coxiella burnetii > 1:800
  • Echocardiogram Evidence of Infective Endocarditis:
    • Vegetation (Oscillating Intracardiac Mass on a Valve or Supporting Structures, in the Path of Regurgitant Jets, or On Implanted Material in the Absence of an Alternative Anatomic Explanation)
    • Abscess
    • New Partial Dehiscence of Prosthetic Valve
    • New Valvular Regurgitation (Worsening or Change of Preexisting Murmur Not Sufficient)

Minor Criteria

  • Predisposition: Predisposing Heart Condition or IV Drug Abuse
  • Fever
  • Vascular Phenomena (Major Emboli, Septic Pulmonary Infarcts, Mycotic Aneurysm, Intracranial Hemorrhage, Conjunctival Hemorrhage or Janeway Lesions)
  • Immunologic Phenomena (Glomerulonephritis, Osler Nodes, Roth Spots or Rheumatoid Factor)
  • Microbiological Evidence (Positive Blood Culture that Does Not Meet Major Criteria or Serologic Evidence of an Active Infection with an Organism Consistent with Infective Endocarditis)

Management

Primary Treatment

  • Primary Treatment: Antibiotics
    • No Role for Anticoagulant or Antiplatelet Therapy (Does Not Prevent Septic Thromboembolic Complications)
  • Considerations:
    • Consider Removal of Any Infected Implanted Devices
    • Obtain Source Control for All Active Oral Infections
    • Consider Colonoscopy for Streptococcus bovis Infections

Surgery Indications

  • Antibiotic Failure
  • Valve Stenosis or Regurgitation Leading to Heart Failure
  • Aortic or Mitral Regurgitation with Elevated Left-Sided End-Diastolic Pressure
  • Fungal Infection or Other Multidrug Resistant Organisms
  • Heart Block
  • Annular or Aortic Abscess
  • Destructive Penetrating Lesions (Fistula, etc.)
  • Recurrent Emboli with Persistent Vegetations
  • Large Mobile Vegetations > 10 mm

Antimicrobial Prophylaxis

  • Regimen: Oral Amoxicillin 30-60 Minutes Prior to Procedure
  • Indication: Highest-Risk Patients Undergoing Procedures Likely to Cause Bacteremia with Potential to Cause Infective Endocarditis
  • Highest-Risk Patients:
    • Prosthetic Heart Valves
    • Prosthetic Material Used for Cardiac Valve Repair
    • History of Infective Endocarditis
    • Congenital Heart Disease:
      • Unrepaired Cyanotic Congenital Heart Disease
      • Repaired Congenital Heart Disease with Residual Shunts or Valvular Regurgitation Near the Prosthetic Device or Patch
      • Within the First 6 Months After Repair of Congenital Heart Defects with Catheter-Based Intervention Using an Occlusive Device or Stent
    • Transplanted Heart with Valve Regurgitation Due to a Structurally Abnormal Valve
  • Indicated Procedures:
    • Dental Work – Highest Risk Procedure
    • Respiratory Tract Procedures
    • Skin or Soft Tissue Procedures
    • Cardiac Surgery with Prosthetic Material
    • *Generally Not Indicated for Gastrointestinal Procedures, Genitourinary Procedures, Vaginal or Cesarean Delivery