Running head: INFECTIVE ENDOCARDITIS PROTOCOL

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INFECTIVE ENDOCARDITIS PROTOCOL

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Infective Endocarditis Protocol
Definition of Infective Endocarditis: Infective endocarditis (IE) is an infection involving the endocardial surface of the heart, including the valvular structures, the chordae tendineae, sites of septal defects, or the mural endocardium. Its intracardiac effects include severe valvular insufficiency, which may lead to intractable congestive heart failure and myocardial abscesses.
IE also produces a wide variety of systemic signs and symptoms through several mechanisms, including both sterile and infected emboli and various immunological phenomena. The incidence of IE is approximately 15,000-20,000 cases per year and affects men twice as often as women. Etiologies: The base for IE is usually the aortic or mitral valve and less commonly, the tricuspid valve with epithelial injury. Accumulation of bacteria, fibrin and platelets creates a thrombin, or vegetation, that may easily become dislodges into circulation
Native valve endocarditis (NVE) can have an underlying cause of rheumatic heart disease, congenital heart disease, mitral valve prolapse and degenerative heart disease.
Prosthetic valve endocarditis (PVE) may present early, shortly after surgery, or late. Infection is usually associated with a local abscess, fistula formation, and valvular dehiscence.
Endocarditis in IV drug users is common and requires a high index of suspicion. Two thirds of patients have no previous history of heart disease or murmur on admission.
Endocarditis may be associated with intravascular devices such as central or peripheral intravenous catheters, rhythm control devices such as pacemakers and defibrillators, hemodialysis shunts and catheters, and chemotherapeutic and hyperalimentation lines.
The most common pathogens are listed below:
• Viridans group streptococci (Strep)
• Staphylococcus aureus (Staph)
• Enterococci
• Coagulase-negative staphylococci
• Haemophilus parainfluenzae (h. influenza)
• Actinobacillus
• Streptococcus bovis
• Fungi (Candida, Aspergillus)
• Coxiella burnetii
• Brucella species
• Culture-negative Haemophilus species, Actinobacillus actinomycetemcomitans,
Cardiobacterium hominis, Eikenella corrodens, and Kingella species (HACEK).

INFECTIVE ENDOCARDITIS PROTOCOL

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Patients who develop NVE in the absence of intravenous drug use commonly present with viridans group streptococci, enterococci, or staphylococci, with other pathogens less frequent.
Intravenous drug users often present with right-sided valvular involvement and are more likely to have S aureus, streptococci, gram-negative bacilli, or polymicrobial infections.
PVE
is most commonly caused by coagulase-negative staphylococci, S aureus, enterococci, or gramnegative bacilli. Early prosthetic valve endocarditis is often caused by Staphylococcus epidermidis. Differential Diagnosis:
• Rheumatic Fever
• Antiphospholipid Syndrome
• Atrial Myxoma
• Nonbacterial thrombotic endocarditis (NBTE)
• Primary Cardiac Lesions
• Lyme Disease
• Polymyalgia Rheumatica
• Reactive Arthritis
• Systemic Lupus Erythematosus
• Thrombotic nonbacterial endocarditis
• Vasculitis
• Temporal arteritis
• Connective tissue disease
• Fever of unknown origin (FUO)
• Intra-abdominal infections
• Septic pulmonary infarction
• Tricuspid regurgitation
History/Clinical Presentation:
History of the following is associated with IE:
• Prior IE
• Artificial heart valves
• Congenital heart disease
• Heart transplant
• Implanted cardiac devices or vascular catheters
• Degenerative valve disease
• Mitral valve prolapse (MVP)
• Hypertrophic cardiomyopathy
• IV drug use

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Fever, possibly low-grade and intermittent, is present in 90% of patients with IE. Heart murmurs are heard in approximately 85% of patients.
One or more of the following classic signs of IE are found