INEFECTIVE ENDOCARDITIS

• Endocarditis is an infection and/or inflammation of the heart's valves or its inner lining of heart (endocardium).
• It is classify into two group based on etiology
  • Non-infectious – Rheumatic Endocarditis (RHD)
  • Infectious- Infective Endocarditis

DEFINITION

• Infective endocarditis (bacterial endocarditis) is an infection of the inner lining of the heart caused by direct invasion of bacteria or other organisms leading to myocardial abscess and heart failure.

Etiology

• Infectious agent
  • Staphylococci (S. aureus )
  • streptococci, (S. viridans; S. bovis, S. pneumoni)
  • enterococci,
  • pneumococci,
  • chlamydia,
  • fungi (eg, Candida, Aspergillus)
  • Rickettsiae
• Predisposing factors
  • Bacteraemia, septicemia and pyaemia
  • Underlying heart disease
  • Impaired host defence
  • Invasive procedure
• High Risk People
  • Prosthetic cardiac valves or prosthetic material used for cardiac valve repair
  • Prior History of bacterial endocarditis (even without heart disease)
  • Congenital heart disease especially cyanotic
  • History of CABG, PTCA, RHD, VHD etc.
  • Cardiac transplant

Pathophysiology

Clinical Manifestations

• The onset of symptoms is usually ~2 weeks or less from the initiating bacteremia
• Symptoms are -
  • High grade fever and chills
  • Arthralgias/ myalgias
  • Abdominal pain
  • Pleuritic chest pain
  • Back pain
  • Anorexia
  • Weight loss
  • Fatigue
• Signs are –
  • Fever
  • Heart murmur – if no murmur with other signs and symptoms may indicate right-sided heart infection
  • Nonspecific signs – petechiae, "splinter" hemorrhages, clubbing, splenomegaly, neurologic changes
  • More specific signs - Osler's Nodes, Janeway lesions, and Roth's Spots
• Nonspecific signs –
  • Petechiae—conjunctiva, mucous membranes
  • Splinter hemorrhages in nail-beds
  • Clubbing of fingers and toes—primarily occurs in patients who have an extended course of untreated infective endocarditis.
  • Neurological changes - Localized headaches, Transient cerebral ischemia, Altered mental status, aphasia
  • Splenomegaly,
• More specific signs –
  • Osler's nodes—painful red nodes on palmds of fingers and toes; usually late sign of endocardial infection
  • Janeway's lesions—light pink macules on palms or soles, nontender, may change to light tan within several days or fade in 1 to 2 weeks; usually an early sign of endocardial infection.
  • Roth's spots on fundi (retinal hemorrhages)

Diagnostic Evaluation

• Varied clinical manifestations and similarities to other diseases make early diagnosis of IE difficult.
• So, for accurate diagnosis use Duke criteria or major and minor criteria to establishing diagnosis.
• Definite Diagnosis from Clinical Criteria: 2 (major) + 0 (minor) or 1 (major) + 3 (minor) or 0 (major) + 5 (minor).

MAJOR CRITERIA

• Blood cultures—at least two positive serial blood cultures.
• Endocardial involvement (diagnosed with echocardiography) —identification of vegetations and assessment of location and size of lesions.
• New valvular insufficiency/regurgitation.
• Development of partial dehiscence of prosthetic valve.

Minor Criteria

• Predisposing cardiac condition or I.V. drug use
• Fever higher than 100.4° F (38° C)
• Vascular factors—pulmonary complication, emboli, Janeway's lesions
• Immunologic factors—Osler's nodes, Roth's spots, rheumatoid factor
• Microbiology—positive cultures, but not meeting major criteria
• Echocardiogram—consistent with disease, but not meeting major criteria

Complications

• Complications may include:
  • Heart failure.
  • Abscesses in the heart.
  • Heart rhythm problems.
  • Heart attack.
  • Stroke.
  • Infections in other organs such as the lungs, brain, or kidneys.

Management

• Goals of Therapy
  • Eradicate infection
  • Definitively treat sequelae of destructive intra-cardiac and extra-cardiac lesions
• I.V. antimicrobial therapy, based on sensitivity of causative agent, for 4 to 6 weeks
  • Bactericidal serum levels of selected antibiotics are monitored by serial titers; if serum lacks adequate bactericidal activity, more antibiotics or a different antibiotic is given.
  • Do not miss the doses of antibiotics because it may have irreversible deleterious consequences. if doses will be missed to ensure that appropriate alternative measures are taken.
• Urine cultures obtained after 48 hours to assess efficacy of drug therapy
• Repeat blood cultures obtained after 48 hours to assess efficacy of drug therapy
• Close follow-up by cardiologist
• Supplemental nutrition
• Surgical Treatment require for Intra-Cardiac Complications
• Surgical intervention for:
  • Acute destructive valvular lesion—excision of infected valves or removal of prosthetic valve.
  • Hemodynamic impairment, severe heart failure
  • Recurrent emboli.
  • Resistant infection
  • Drainage of abscess or empyema
  • Repair of peripheral or cerebral mycotic aneurysm.

Nursing Management

Nursing Diagnoses

• Pain related to inflammation
• Activity intolerance related to imbalance between oxygen supply and demand
• Hyperthermia related to infection

Nursing intervention

• Assess heart sounds for new or worsening murmur.
• If patient received surgical treatment, provide post-surgical care and instruction.
• After surgery, monitor patient's temperature; a fever may be present for weeks.
• Monitor for signs and symptoms of systemic embolization, or, for patients with right heart endocarditis, signs and symptoms of pulmonary infarction and infiltrates.
• Assess for signs and symptoms of organ damage such as stroke (CVA, brain attack), meningitis, heart failure, myocardial infarction, glomerulonephritis, and splenomegaly.
• Instruct patient and family about activity restrictions, medications, and signs and symptoms of infection.
• Reinforce that antibiotic prophylaxis is recommended for patients who have had infective endocarditis and who are undergoing invasive procedures.