INFECTIVE ENDOCARDITIS

1. Infective
Endocarditis
BY DR SALMAN MUSTAAN KHAN

2. Definition
 Inflammation of the inner linings of the heart’s
chambers and valves.
 Represents a complex interplay between a pathogen
and host factors such as endothelial disruption and
immune function.

3. Overview
 Significant cause of mortality and morbidity in children
 Often a complication of congenital heart disease or
rheumatic heart disease in children but can occur
without the presence of any abnormal valves or
cardiac malformations

4. Pathogenesis
 Turbulent blood flow because of a hole or stenotic
orifice or a high pressure gradient across a gradient
 Traumatizes the vascular endothelium
 Creating a substrate for deposition of platelets and
fibrin leading to formation of a non bacterial
thrombotic embolus that is an initiating lesion
 A substrate for infection
 Bacteremia appears leading to proliferation of bacteria
within the lesion

5. Cont’d

7. Common causative agents
 Viridans Streptococci(alpha hemolytic)(poor dental hygiene
dental procedures etc)
 Staphylococcus aureus(more common with indwelling
catheters, IV drugs abuse)
 Haemophilus influenzae
 Brucella
 Neisseria gonorrhoeae
 Chlamydia
 Pseudomonas Aeroginosa
 Fungi

8. Clinical manifestations
 Important history points: Prior congenital or rheumatic
heart disease, preceding dental, urinary tract or
intestinal procedures, IV drug use, Central venous
catheter, prosthetic valve
 Symptoms: Fever, chills, chest and abdominal pain,
arthralgia, myalgia, dyspnea, malaise, weakness,
night sweats, weight loss, CNS manifestations like
stroke, seizures, headache)

9. Clinical signs
 Elevated temperature
 Tachycardia
 Embolic phenomena like Roth spots, petechiae, splinter nail
bed hemorrhages, osler nodes, CNS or ocular lesions
 Janeway lesions
 New or changing murmur
 Splenomegaly
 Arthritis
 Heart failure and arrhythmias
 Metastatic infection like meningitis, mycotic arterial aneurysm,
pericarditis, abscess, septic pulmonary embolism
 Clubbing

11. Diagnosis
 Blood cultures.
 Duke’s criteria
 Echocardiography

12. Blood cultures
 Can be negative in less than 6% cases
 Three or more cultures required
 Three to five collection of blood specimen from
different sites
 In 90% cases, pathogen is recovered in first two
cultures
 May need a PCR test if culture isn’t conclusive

13. Echocardiography
 Transesophageal or transthoracic two dimensional
echocardiography
 When combined with doppler studies, the presence of
valve dysfunction can be identified
 Lesion greater than 1cm is at greater risk of
developing embolization

15. Treatment
 Antibiotic therapy including penicillin, vancomycin plus
gentamycin, cephalosporins like ceftriaxone etc
 At least 4 weeks therapy
 Heart failure therapy like diuretics, afterload reducing
agents etc
 Surgery if severe aortic, mitral or prosthetic valve
involvement with intractable heart failure