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Endocarditis

• Endocarditis is an infection of the cardiac tissue
• The most common pathogens
  • Strep viridans
  • Staph aureus
  • Enterococci
• Get the diagnosis flow sheet here  (sorry this is no longer available)

Risk Factors

• Prior endocarditis
• Damaged heart tissue or valves
  • Mitral rugurge
  • Aortic stenosis
  • Etc
• Prosthetic valve
• Post op valve replacement
  • Infection is most common in the first two months
  • The most common organisms in a post op infection are
    • Staph aureus
    • Fungi
    • Gram-negative bacteria
• Any event which may introduce bacteria into the circulatory system
  • Dental work
  • IV drug use -Most common bug is Staph aureus due to needle contamination
  • Central line placement
  • Surgery on infected tissue
  • Upper respiratory procedures including tonsillectomy or adenoidectomy
  • GI procedures
  • Urinary procedures
  • etc

Clinical presentation

Non specific signs of infection
– Fever/Chills
– Fatigue
– Loss of appetite
– Arthralgias

Physical Exam findings

• A new or changed heart murmur
• Embolic events
  • Embolus is an unattached mass that travels through the bloodstream
  • Splinter hemorrhages – small black lines in the nails
  • Janeway lesions – nontender, macular lesions most commonly involving the palms and soles.
  • Petechia – 1–2 mm purple spot on the skin
  • Signs of neurologic deficit
• Immunologic events
  • Antigen + antibody = immune complex which may travel and cause vasculitis or a blockage of a blood vessel
  • Osler nodes – painful, palpable, erythematous lesions most often involving the pads of the fingers and toes.
  • Roth spots – Retinal hemorrhages with white centers (very rare)
  • Glomerulonephritis

Labs and Studies

• Three blood cultures at least one hour apart from each other.
• CBC
• C reactive protein
• Sed rate
• BUN/CR
• BMP
• ECG will likely be normal
• Echo/Transesophageal – may show the affected heart valve

Diagnosis

• Duke criteria established in 1994 and revised in 2000 has been used to diagnose endocarditis. The Duke criteria requires one of the following be met for the diagnosis to be made clinically.
  • Two major criteria
  • One major criteria and three minor criteria
  • Five minor criteria
• Get the diagnosis flow sheet here  (sorry this is no longer available)

Major Criteria

• Positive blood
  • Must show organism consistent with endocarditis including
    • Strep viridans
    • Strep bovis
    • Staph aureus
    • Enterococci
    • HACEK
      • A group of gram negative bacteria which rarely cause of endocarditis and may be found in the oropharyngeal region
      • Haemophilus
      • Aggregatibacter
      • Cardiobacterium
      • Eikenella
      • Kingella
  • Must have 2 positive cultures at least 12 hours apart or 3 positive cultures drawn at least one hour apart.
• Positive echo findings
  • New regurgitation
  • Abscess
  • Oscillating mass

Minor Criteria

• Predisposing factor
  • Cardiac lesion
  • Any procedure which may introduce bacteria into the bloodstream
  • IV drug use
• Fever > 38 C or 100.4 F
• Embolic events
  • Splinter hemorrhages
  • Janeway lesions
  • Petechia
  • Signs of neurologic deficit
• Immunologic events
  • Osler nodes
  • Roth spots
  • Glomerulonephritis
• Positive blood culture not satisfying a major criteria

Treatment

• Medical
  • Prophylactic antibiotics use for patients with predisposing cardiac issues undergoing higher risk surgical procedures.
    • Oral Amoxicillin 1 hour before the procedure
  • In an acute setting empiric antibiotics are started after the first positive culture
    • Begin with vancomycin and ceftriaxone until cultures and susceptibilities are complete
  • Four to six weeks of IV antibiotic treatment
• Surgical
  • Valve replacement
  • Debridement of abscess or infected material

Pericarditis

Pericarditis is the inflammation of the pericardium. The pericardium is a double layer membrane that contains the heart.

Causes

• Viral infection is the most common cause
  • Echovirus
  • Coxsackie
  • Flu
  • HIV
  • Mumps
• Bacterial infection is rare and typically follows a respiratory infection
  • Pneumococcus
  • Tuberuclosis
• Post MI – Dressler Syndrome
• Post cardiac surgery
• Radiation
• Autoimmune
• Kidney failure
• Trauma

Clinical Presentation & Physical Exam Findings

• Sharp pleuritic chest pain
• Pain is affected by position
  • Aggravated by deep breathing or lying down
  • Alleviated by leaning forward
• Dyspnea
• Diaphoresis
• Fever
• Dry cough
• Patients may appear extremely ill
• Pericardial friction rub may be heard on the lower left sternal border

Labs & Studies

• CBC with elevated WBC’s
• BUN and CR may be elevated
• ECG
  • Diffuse ST- T elevation (think heart attack everywhere)
• The following tests will not have very specific findings for pericarditis, but will help rule out other disease processes and possible causes of the pericarditis
• Echo
• CT/MRI
• Cardiac enzymes
• Tap of pericardial effusion
• Pericardial biopsy

Treatment

• Treat underlying cause
  • Antibiotics
  • Antifungals
  • Dialysis
  • etc
• Aspirin and high doses of NSAIDS to reduce inflammation
• Corticosteroids if NSAIDS are not effective but increase the risk of recurrence
• Colchicine may be effective
• Diuretics
• Pericardiocentesis if effusion and tamponade occur
• Pericardiotomy

Pericardial Effusion and Tamponade

• Pericardial effusion is an increase in fluid within the pericardium.
• Cardiac tamponade is when the pressure from a pericardial effusion constricts the heart to a point where it begins to affect cardiac output.

Causes

• Most commonly cause is pericarditis
• Congestive Heart Failure
• Myxedema
• Trauma

Clinical Presentation

• Symptoms are similar to pericarditis

Physical Exam Findings

• Hypotension
• Jugular venous distension
• Tachycardia
• Tachypnea
• Paradoxical pulse pressures – a drop of more than 10 mmHg in systolic blood pressure during inspiration.
• Narrow pulse pressure
  • 40 mmHg is normal (120–80)
• Decreased heart sounds

Labs & Studies

• Chest X-ray – Water bottle heart
• ECG
  • Nonspecific T wave changes with low QRS voltages
  • Electrical alternans is pathognomonic – the QRS amplitudes fluctuate beat to beat.
• Echo – diagnostic
• Pericardiocentesis for culture and cytology

Treatment

• Small, stable effusions may be watched carefully
• Treat underlying cause
• Pericardiocentesis may be required
• Pericardiectomy

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