Published: European Heart Journal (2023), 44:3948–4042 Societies: ESC (European Society of Cardiology), endorsed by EACTS & EANM DOI:10.1093/eurheartj/ehad193
The revised criteria incorporate imaging advances and expanded pathogen recognition. Diagnosis requires definite, possible, or rejected classification based on major and minor criteria.
Major Criteria
1. Blood Cultures Positive for IE
Typical pathogens: oral streptococci, S. gallolyticus, S. aureus, HACEK group, E. faecalis
≥2 positive blood cultures from separate draws OR ≥3 out of 4 separate cultures
Single positive blood culture for C. burnetii (phase I IgG antibody titre >1:800)
2. Imaging Positive for IE
Echocardiography (TTE or TOE): vegetations, perivalvular/prosthetic lesions
Diagnostic Approach: Serology for Coxiella burnetii, Bartonella, Brucella; blood/tissue culture on specialized media; 16S rRNA/ITS sequencing; [18F]FDG-PET/CT.
Empiric Antibiotic Therapy
Recommended until culture results: Ceftriaxone 2g IV BD + Gentamicin 3 mg/kg IV daily + Ampicillin 2g IV QID (covers enterococci). Adjust within 24–48 hours based on organism identification and susceptibilities.
Antibiotic Regimens
Native Valve Endocarditis (NVE): Streptococci
Penicillin-Susceptible: Penicillin G 12–18 MU IV daily in 4–6 doses for 4 weeks OR Ceftriaxone 2g IV daily for 4 weeks ± gentamicin 3 mg/kg IV daily for 2 weeks.
Penicillin-Resistant: Penicillin G 24 MU IV daily for 4 weeks + gentamicin 3 mg/kg IV daily for 2 weeks OR Ceftriaxone 2g IV daily for 4 weeks + gentamicin.
Native Valve Endocarditis: Staphylococcus aureus
MSSA (Standard): Flucloxacillin 12g/day IV in 4–6 doses for 4–6 weeks OR Cefazolin 6g/day IV in 3 doses for 4–6 weeks ± gentamicin 3 mg/kg IV daily for first 3–5 days.
MRSA: Vancomycin 30–60 mg/kg IV daily (target trough 15–20 µg/mL) for 4–6 weeks + gentamicin 3 mg/kg IV daily for 2 weeks + rifampicin 900 mg/day in 3 divided doses.
Native Valve Endocarditis: Enterococcus
Beta-Lactam Susceptible: Ampicillin 12g/day IV in 4–6 doses for 6 weeks + gentamicin 3 mg/kg IV daily for 2 weeks.
Beta-Lactam Resistant: Vancomycin 30–60 mg/kg IV daily + gentamicin 3 mg/kg IV daily for 6 weeks.
Prosthetic Valve Endocarditis (PVE)
Key Point: Antibiotic durations are longer (≥6 weeks) due to increased relapse risk and local complications.
Streptococci: Same drugs as NVE but 6 weeks duration
Enterococcus: Ampicillin + gentamicin 6 weeks (or vancomycin-based if resistant)
Outpatient Parenteral Antibiotic Therapy (OPAT)
Criteria for Switch: Clinical stability, infection control, completion of inpatient phase ≥10 days, no major complications.
Facilitates early discharge and improves quality of life while maintaining therapeutic efficacy. Continue same IV antibiotics or switch to oral step-down if susceptibility allows.
Surgical Indications & Timing
Surgery in IE aims to remove infected material and address hemodynamic consequences. Up to 20% of IE patients require surgery in the acute phase.
Three Main Indications
1. Heart Failure (40%)
Acute severe regurgitation causing pulmonary edema/cardiogenic shock
Septal perforation, prosthetic valve dehiscence
Timing: Emergency within 24h if cardiogenic shock; Urgent 3–5 days if controlled HF
2. Uncontrolled Infection (40%)
Persistent positive blood cultures >7 days despite antibiotics
Local complications: perivalvular abscess, pseudoaneurysm, fistulae
Resistant organisms: fungi, MRSA, Gram-negatives
Timing: Urgent 3–5 days; Non-urgent within same admission if controlled
3. Prevention of Systemic Embolism (20%)
Large mobile vegetations ≥10 mm
Documented systemic/pulmonary embolism
Anterior mitral valve vegetations (highest risk)
Timing: Urgent 3–5 days if recurrent emboli despite antibiotics
Timing
Time Frame
Clinical Scenario
Emergency
Within 24h
Cardiogenic shock, pulmonary edema refractory to medical therapy
Urgent
3–5 days
Uncontrolled infection, large vegetations, severe HF
Non-urgent
Same admission
IE controlled, hemodynamics stable
Imaging: Echocardiography, CT, PET/CT, MRI
Transthoracic & Transesophageal Echocardiography
First-line diagnostic modality. TTE should be performed urgently in all suspected IE; TOE recommended if TTE inconclusive.
TOE Advantages: Superior sensitivity (85–95% vs 60%), better visualization of posterior structures and prosthetic valves, 3D reconstruction for surgical planning.
Cardiac Computed Tomography (CT)
Recommended in: Suspected NVE, PVE, paravalvular complications, aortic root pathology, inconclusive echo. Highly sensitive for small vegetations and abscesses.
[18F]FDG-PET/CT & WBC SPECT/CT
Recommended for: IE and cardiac complications diagnosis, detection of distant septic emboli, CIED-related IE, inconclusive echocardiography. Sensitivity 65–90%, Specificity 85–90%.
Brain Imaging (MRI & CT)
Mandatory when neurological complications suspected (stroke, TIA, mycotic aneurysm). MRI more sensitive for small lesions; CT useful for acute hemorrhage.
Complications of Infective Endocarditis
Embolic Events (20–50%)
Large, mobile vegetations carry highest embolic risk. Risk highest during early antibiotic therapy due to inflammation and bacterial biofilm breakdown.
Leading indication for urgent/emergency surgery. Caused by acute valvular regurgitation, septal perforation, or myocarditis.
Uncontrolled Infection
Persistent positive blood cultures >7 days despite appropriate antibiotics. Indicates insufficient antimicrobial efficacy or inaccessible infection source.
Neurological Complications (30–80%)
Most common: ischemic stroke from septic emboli. Also mycotic aneurysms, intracerebral hemorrhage, meningitis. S. aureus more frequently associated with neurological complications.
Pearl: Early cardiac surgery in high-risk neurological IE patients improves outcomes. Timing must balance hemorrhagic risk against embolic risk.
Perivalvular Abscess & Mycotic Aneurysms
Abscess: Detected by TOE, cardiac CT, PET/CT; often requires surgical drainage
Mycotic Aneurysms: Rare but serious; septic seeding of arterial walls; risk of rupture and hemorrhage; endovascular or neurosurgical intervention often needed
Prosthetic Valve Endocarditis
PVE is the most severe form of IE with higher mortality and morbidity than NVE. Surgical management often necessary.
Epidemiology
Incidence: 0.3–1.2% per patient-year
Early PVE (<1 year): S. aureus, Gram-negatives common (surgical contamination)
Late PVE (>1 year): Similar to NVE organisms
Mechanical valves higher risk than bioprostheses
Diagnosis of PVE
More challenging than NVE due to prosthetic material artifact. TOE essential; Cardiac CT helpful for perivalvular abscesses; [18F]FDG-PET/CT improves accuracy.
Management
Antibiotic Duration: ≥6 weeks minimum (longer than NVE).
Surgical Indications: Early valve replacement more frequently needed in PVE due to prosthetic valve dehiscence, paravalvular abscess, uncontrolled infection, systemic emboli.
Prognosis: In-hospital mortality 20–40% (higher than NVE). Early surgical intervention improves outcomes.
Cardiac Device-Related Infective Endocarditis
Definition
CIED-related IE involves the device, leads, or cardiac valves. Two categories: pocket infection (superficial) and lead-related/valvular IE (systemic).
Antibiotic therapy for S. aureus: flucloxacillin/cefazolin 4 weeks OR vancomycin 4–6 weeks if MRSA
Gentamicin first 2 weeks optional but recommended
Success rates 70–90% with appropriate antibiotics and close follow-up
Surgical Indications
Severe tricuspid regurgitation with HF refractory to diuretics
Large vegetations (>20 mm) with recurrent septic pulmonary emboli
Prosthetic valve IE with dysfunction
Uncontrolled infection with Gram-negative or fungal organisms
Surgical Options & Prognosis
Tricuspid valve repair preferred over replacement (better outcomes)
Generally better prognosis than left-sided IE (5–15% mortality with medical management)
High recurrence in IVDU without addiction treatment
Infective Endocarditis Prophylaxis
Antibiotic prophylaxis reduces bacteremia after dental and certain medical procedures. Indicated in high-risk patients undergoing procedures with significant bacteremia risk.
High-Risk Patients
Previous IE
Prosthetic heart valves (mechanical or bioprosthetic)
Complex cyanotic heart disease (unrepaired or residual defects)
CHD repaired with prosthetic material <6 months
Transposition of the great arteries, tetralogy of Fallot with residual shunt
2023 ESC Guidelines for the management of infective endocarditis. Developed by the Task Force on Infective Endocarditis of the European Society of Cardiology (ESC). Endorsed by EACTS and EANM.
Published: European Heart Journal (2023), 44(48):3948–4042
Recommendation Classes
Class I Recommended or indicated
Class IIa Should be considered
Class IIb May be considered
Class III Not recommended
Levels of Evidence
Level A Multiple RCTs or meta-analyses
Level B Single RCT or large non-randomized studies
Level C Expert consensus or small studies
Disclaimer: This quick reference is a condensed educational summary of the 2023 ESC Guidelines. For complete details, recommendations, and evidence tables, consult the full guideline published in the European Heart Journal. Clinical decisions should always be individualized based on patient factors, local epidemiology, and expert consensus within the Endocarditis Team.