Dr Amera Alkaisi

PhD Oral and Maxillofacial Surgery . USM . Malaysia

Endocarditis

Is an infection of the inner lining of the heart (endocardium).The infection usually involves one or more heart valves which are part of the endocardium

Classification

Clinically divided according to its duration

1. Acute bacterial endocarditis Affect normal valves

Occur over days or weeks

Staphylococcus aureus

High virulence

2. Subacute bacterial endocarditis

Often affect damaged valves Caused by  streptococci of low virulence Mild to moderate illness which progresses slowly over weeks and months• Has low propensity to hematogenously seed extracardiac sites.

New classification that is based on

The causative microorganism \

The type of valve that is infected Native valve endocarditis [NVE] Prosthetic valve endocarditis [PVE] Source of infection

Community-acquired Hospital-acquired whether the patient is an intravenous drug user (IVDU)

Causes

Many microorganisms can cause infective endocarditis

Streptococci viridans Alpha-hemolytic streptococci, Present in the mouth are the most frequently isolated micro-organisms

Enterococcus Enter the blood stream as a consequence of abnormalities in the gastrointestinal or genitourinary tracts

Staphylococcus aureus They can enter the blood stream through procedures that cause break in the integrity of skin like surgery

Fungal and Viral Fungi are seen less frequently.

Candida albicans, yeast, Associated with endocarditis in IV drug users.

Risk factors

Congenital heart defectsArtificial heart valvesHistory of endocarditis(Chronic rheumatic heart disease)History of intravenous (IV) illegal drug use, cause contamination

The organism may enter the bloodstream through:

• Everyday oral activities Brushing the teethChewing food can especially if the teeth and gums aren't healthy An infection or other medical conditionSkin soreGum disease Intestinal disorder such as inflammatory bowel disease Certain dental procedures (Gingivectomy)

PATHOPHYSIOLOGY

Signs and symptoms

•Fever and chills

•A new or changed heart murmur heart sounds made by blood rushing through the heart

• Immunologic responses

Neurological Sgns

Embolic stroke

Intracerebral hemorrhage

Multiple micro abscesses

Other signs of IE may include the following

•Fatigue• Paleness•Night sweats•Shortness of breath•Persistent cough•Swelling in the feet, legs or abdomen• Unexplained weight loss

•Hematuria (Blood in in urine) •Splenomegaly•Clubbing of the digits•Aching joints and muscles•Paralysis, hemiparesis, aphasia•Conjunctival hemorrhage•Cardiac arrhythmia•Chest pain

Investigations

Blood culturesThree separate sets of blood cultures from different sites obtained over a 24-hour period

EchocardiographyAs soon as possible (ideally within 24 hours) Transthoracic echocardiogram Transesophageal

To show the presence and size of vegetations

Vegetation (Arrow )on the tricuspid valve by echocardiography.

Diagnostic criteria 

Duke criteria

Collection of major and minor criteria used to establish a diagnosis of infective endocarditis (Established in 1994 by the Duke Endocarditis Service)

The diagnosis according to this criteria could be

Definite, possible, or rejected

One of these pathological criteria

Histology or culture of a cardiac vegetation, an embolized vegetation, or intracardiac abscess from the heart finds microorganisms

Active endocarditis

• One of these combinations of clinical criteria

2 major clinical criteria

1 major and 3 minor criteria

5 minor criteria

Major criteria

Positive findings on echocardiography

Positive blood culture with typical IE microorganism

Minor criteria

• Predisposing heart condition or IV drug use• Fever >38°C• Janeway lesions,•  conjunctival hemorrhage•, Roth's spots• Rheumatoid factor

Treatment

Surgery

Valve repair if the damage is less severe

Replacing a damaged valve with an artificial valve.