infective endocarditis
Skip this Video
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 55


  • Uploaded on

INFECTIVE ENDOCARDITIS. Manoj Kuduvalli. Definition. Bacterial or Fungal infection within the heart (although chlamydial and rickettsial infections are known) ; the role of viruses is unknown. ORIGINAL CLASSIFICATION (Prior to Antibiotic era). Current Criteria for Classification.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'INFECTIVE ENDOCARDITIS' - Patman

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
infective endocarditis


Manoj Kuduvalli



Bacterial or Fungal infection within the heart (although chlamydial and rickettsial infections are known) ; the role of viruses is unknown

current criteria for classification

Current Criteria for Classification

Underlying Anatomy:

› Native Valve Endocarditis

› Prosthetic Valve Endocarditis

Infecting Organism

› Serves as basis for therapy and prognosis

native valve endocarditis underlying predisposing conditions

Native Valve EndocarditisUnderlying Predisposing Conditions

›› 60 - 80% of non IV Drug abusers have a

predisposing condition

› Mitral Valve Prolapse 30 - 50%

› Rheumatic Heart Disease 20 - 40%

› Degenerative Aortic and 20 - 30%

Mitral valve disease

› Congenital Heart Disease 10 - 20%

native valve endocarditis microbiology

Native Valve EndocarditisMicrobiology

›› Streptococci 50 - 70%

Viridans Streptococci (50% of all Strep)

›› Staphylococci ~ 25%

Mostly Coagulase +ve Staph. Aureus

Staph. Epidermidis

›› Enterococci ~ 10%

native valve endocarditis microbiology7
Viridans Streptococci

Infect primarily abnormal valves

Indolent clinical course

Highly sensitive to Penicillins

Staph. aureus

Infect normal and abnormal valves

Fulminant course with rapid destruction of valves and multiple metastatic abscesses

Mostly resistant to Penicillins and sensitive to penicillinase resistant ß-lactams

Common with soft tissue infections, and infected IV catheters

Native Valve EndocarditisMicrobiology
native valve endocarditis microbiology8
Staph. Epidermidis

Indolent Course

Affects abnormal valves


Normally affects damaged valves

Recent history of genitourinary or gastrointestinal manipulation, disease or trauma

Usually sensitive to Penicllin+Gentamicin

Resistant strains prevalent

Native Valve EndocarditisMicrobiology
prosthetic valve endocarditis
Prosthetic valve endocarditis
  • 5 - 15% of all Infective Endocarditis
  • Overall incidence 1 - 4%
  • Risk of PVE peaks at 15 days postop. , then rapidly declines by 150 days
prosthetic valve endocarditis classification
Early ( < 60 days )

Reflects perioperative contamination

Incidence around 1%


Staph (45 - 50%)

Staph. Epiderm (~ 30%)

Staph. Aureus (~ 20%)

Gram -ve aerobes (~20%)

Fungi (~ 10%)

Strep and Entero (5-10%)

Late ( > 60 days)

After endothelialization

Incidence 0.2 -0.5 % / pt. year

Transient bacteraemia from dental, GI or GU


resembles native valve endocarditis

Prosthetic Valve EndocarditisClassification
ie in iv drug abusers

IE in IV Drug Abusers

Right sided predilection

Tricuspid Valve ~ 55%

Aortic Valve ~ 25%

Mitral Valve ~ 20%

Pulmonary Valve 1 - 1.5%

Mixed Rt. And Lt. Side 5 - 6%

ie in iv drug abusers12
IE in IV Drug Abusers
  • Skin most predominant source of infection
  • Also contamination of drugs and paraphernalia
  • 70 - 100% of Rt. sided IE results in pneumonia and septic emboli
  • Microbiology
    • Staph aureus ~60%
    • Streptococci and Enterococci ~20%
    • Gram -ve bacilli ~10%
    • Fungi (Candida and Aspergillus ~5%
ie in adults with congenital heart disease

IE in adults with congenital heart disease

Common defects


Bicuspid AV PS

Coarctation of Aorta

Occurs in defects with

--mild or no hemodynamic consequences

--high gradients

--high velocity jets impinging on endocardium


Microbiology very important since virulence of the infecting organism is a significant factor in determining the success rates of both medical and surgical treatment



Requires interaction between

› Host vascular endothelium

› Host haemostatic response

› Adventitiously circulating organisms

hemodynamic factors predisposing to infective endocarditis
Hemodynamic factors predisposing to Infective Endocarditis
  • High velocity abnormal jet stream
  • Flow from high to low pressure chamber
  • Narrow orifice between two chambers creating pressure gradient


Initially affects

Valve leaflets in native valve endocarditis

Can extend into annulus

Annulus in prosthetic valve endocarditis

Due to presence of sewing rim

pathology embolic phenomena
Pathology -Embolic Phenomena
  • Incidence
    • Clinically 15 - 45%
    • Pathologically 45 - 65%
  • More with large mobile vegetations
    • Fungi (Candida and Aspergillus)
    • Group B and G Streptococci
    • Staph aureus
  • Result in
    • Infarcts
    • Abscesses
    • Mycotic aneurysms
pathology immune complex associated
PathologyImmune Complex Associated
  • Glomerulonephritis
  • Arthritis
  • Osler’s nodes
clinical features

Clinical Features

Onset usually within 2 weeks of infection

› Indolent course

- Malaise

- Fatigue

- Night sweats

- Anorexia

- Weight loss

› Explosive course


- S/o severe systemic sepsis

clinical features25

Clinical features

› Fever

- Usually < 39 °C, remittent

- May be absent in

- elderly

- severe debility


- Already on antibiotics

› Murmurs

- Appearance of new murmur or true

change in existent murmur indicates

infection with virulent organism

other clinical features
Other Clinical Features
  • Splenomegaly ~ 30%
  • Petechiae 20 - 40%
    • Conjunctivae
    • Buccal mucosa
    • palate
    • skin in supraclavicular regions
  • Osler’s Nodes 10 - 25%
  • Splinter Haemorrhages 5 - 10%
  • Roth Spots ~ 5%
  • Musculoskeletal (arthritis)
  • Congestive Cardiac Failure (Commonest complication)
      • Valve Destruction
      • Myocarditis
      • Coronary artery embolism and MI
      • Myocardial Abscesses
  • Neurological Manifestations (1/3 cases)
      • Major embolism to MCA territory ~25%
      • Mycotic Aneurysms 2 - 10%
  • Metastatic infections
    • Rt. Sided vegetations
      • Lung abscesses
      • Pyothorax / Pyopneumothorax
    • Lt. Sided vegetations
      • Pyogenic Meningitis
      • Splenic Abscesses
      • Pyelonephritis
      • Osteomyelitis
  • Renal impairment d/t Glomerulonephritis
  • Blood Cultures
    • Positive in 95% cases
  • Other Laboratory Parameters
    • Anaemia
    • Leucocytosis (WCC may be normal in indolent infection)
    • Thrombocytopenia
    •  ESR (may be absent in CCF and renal failure)
    • Urine - Microscopic hematuria / proteinuria
  • Can demonstrate lesion / vegetation in 60 - 80% of cases
  • Difficult in prosthetic valve endocarditis
  • TOE better than TTE
  • Can demonstrate
    • Morphology of valve
    • Annular abscesses
    • Hemodynamics of the valves
  • Serial observations can contribute to decision for surgery




principles of medical management

Principles of Medical Management

Sterilization of Vegetations with antibiotics

- prolonged Slowly metabolising bacteria

due to high density, hence  sensitivity

- high dose

Bacteria deep inside



principles of medical management33

Principles of Medical Management

Acute onset, fulminant

-Within two to three hours of

clinical diagnosis.

-Take cultures, but do not wait

for results

Timing of Therapy

Subacute onset, or having

received recent antibiotic

-Within two to three days. -Can wait for culture reports

principles of medical management34
Principles of Medical Management
  • Isolation of organisms very important
  • Therapy before isolation of organism
      • Native valve endocarditis and in IV drug abusers
        • Directed against Staph aureus
      • Prosthetic valve endocarditis
        • Broad spectrum antibiotics directed against
          • Staph aureus
          • Staph epidermidis
          • Gram –ve bacilli
indications for surgery left sided native valve endocarditis
Indications for SurgeryLeft sided native valve endocarditis
  • Valvular disruption leading to severe insufficiency and CCF
  • Extravalvar extension
  • Embolization of vegetations
  • Failure of medical management

Positive blood culture and systemic signs of infection after “adequate” antibiotic therapy

  • Resistant organisms

such as MRSA, Fungi , Pseudomonas

  • Echo detected vegetation > 1 cm ??
indications for surgery right sided native valve endocarditis
Indications for SurgeryRight sided native valve endocarditis

Indications differ because:

- Consequences of valve disruption and emboli are less

- Success with antibiotics seems to be better

--Failure of medical treatment

--CCF, with its complications Indications (elective)

--Recurrent pulmonary emboli

with complications

--Extravalvar spread (rare)

indications for surgery prosthetic valve endocarditis
Indications for surgeryProsthetic valve endocarditis
  • Early infection almost always require surgery
  • Late infection

Antibiotic therapy succeeds more often with

Bioprosthesis compared to mechanical valves

CCF due to prosthesis dysfunction

Indications Multiple emboli

Persistent infection

indications for surgery special situations

Indications for SurgerySpecial situations


Not usually indicated since life expectancy due to AIDS very poor

HIV +ve patient without AIDS

IV Drug Abusers

No change in indications since enough number survive > 10 years

when to operate

When to operate ?

As soon as there is a major indication

Valid reasons for delay

Acute CNS injury

--Hemorrhagic infarct (Wait for 10 days to allow healing)

--Coma (very poor prognosis )

Renal failure due to Glom’nephritis

Follow through the acute phase

(Prerenal failure -- early operation)

principles of operation

Principles of operation

Repair or Replacement ?

(More important with mitral valves)

Repair contemplated only if:

--Infection well controlled

--Repair structurally feasible after involved tissue excised

principles of operation41
Principles of operation
  • Early operation once indicated
  • Preop. knowledgeof morphology of valve
  • Good exposure(may be difficult in mitrals)
  • Excision and debridement of all infected or involved tissue even if extensive reconstruction or permanent pacing required
principles of operation42
Principles of operation
  • Lookfor extravalvar extension
  • If present,evacuate abscess cavity and repairwith biological material such as autologous or bovine pericardium
  • Suturevalve onto clean and relatively strong tissue
  • Temporary pacing leads

Stented Bioprosthesis


Which Prosthesis?

Stentless Bioprosthesis


choice of prosthesis

Choice of prosthesis

Important factor is location of infection

-- Infection of cusps only:

Choice does not matter, since all infected tissue is usually excised

-- Perivalvar extension:

No choice between mechanical and stented bioprosthesis (both with cloth sewing rims)

Homograft, maybe stentless bioprosthesis have lesser incidence of infection

choice of prosthesis mechanical v s bioprosthetic
Choice of prosthesisMechanical v/s Bioprosthetic
  • No difference in linearized rates for recurrent or residual infection (~1-2% per patient year)
  • No difference in operative mortality and complication free survival
  • Infected bioprosthesis more easily sterilized (since infection initially involves leaflets)
  • However, infection in bioprosthesis may hasten SVD due to damage to leaflets
choice of prosthesis homograft v s others
Choice of prosthesisHomograft v/s others
  • Hazard function for recurrent endocarditis has only low constant phase and has no high early hazard phase like other prosthesis
  • Homograft best choice if valved conduit is required for root replacement ( > 50% annular dehiscence or aortoventricular discontinuity)
postoperative antibiotics

Postoperative Antibiotics

To continue for 6 weeks if

› Operated for --Acute fulminant infection

--Failure of medical therapy

--Resistant organisms

› Excised valve yields positive cultures

› Periannular involvement

› Valve culture –ve, but organisms seen on


› Positive blood cultures 3 – 4 days postop.

results of treatment native valve endocarditis medical management

Results of TreatmentNative valve endocarditisMedical Management

Mortality 10 – 60 %

Risk Factors

Virulent organisms s/a MRSA, G-ve bacilli, fungi


Persistence of systemic sepsis

Major septic embolus

Extravalvar extension

Acute renal failure

results of treatment native valve endocarditis surgical management

Results of TreatmentNative valve endocarditisSurgical Management

Hospital Mortality 5 – 20%

Risk factors

Virulent organisms

Perivalvar extension

Intractable CCF

Renal and multiorgan failure

results of treatment native valve endocarditis surgical management50

Results of TreatmentNative valve endocarditisSurgical Management

Recurrent Endocarditis ~ 2%

Most occurs within 2 months post op.

Same organism

No fresh source of infection

Perivalvar leaks 3-7%

results of treatment prosthetic valve endocarditis medical management

Results of TreatmentProsthetic valve endocarditisMedical Management

Mortality ~ 70%

Risk factors

Valve incompetence or perivalvar leak

Early postoperative onset

Virulent organism

results of treatment prosthetic valve endocarditis surgical management

Results of TreatmentProsthetic valve endocarditisSurgical Management

Hospital Mortality 0 –22%

Risk factors

Early postoperative infection

Virulent organism

Perivalvar extension

Delay in operation

results of treatment prosthetic valve endocarditis surgical management53
Results of TreatmentProsthetic valve endocarditisSurgical Management
  • Long term results differ from valve replacement for NVE or other lesions
  • Have comparatively unfavourable rates of late death, recurrence of infection and reoperation
antibiotic prophylaxis

Antibiotic Prophylaxis

Protocol usually followed recommended by Dajani et al in JAMA 1990

Recommended in following conditions

Prosthetic valves

Previous history of infective endocarditis (even without underlying heart disease)

Most congenital heart diseases

Rheumatic or other acquired valve disease


MVP with MR