Infective Endocarditis

Endocarditis

Encocarditis is the inflammation of the inner tissue of the heart AKA the Endocardium. It usually involves the heart valves (natural or prosthetic valves).

Infective Endocarditis

Infective Endocarditis is a form of endocarditis in which the causative agent is an infectious agent (most commonly bacteria) but other agents as well could be the cause.

Mechanism of Infection

To begin with, micro organisms usually live in our mouth, skin, intestine and urinary track, but not in our blood. However some microorganisms can enter the bloodstream (via surgery or dental procedure).

For most people theses microorganisms don’t pose a threat to the body and are dealt with by the immune system, but if one the heart valves becomes or are damaged (e.g Rheumatic Fever or prosthetic valve surgery). The body will typically heal those valves by sending immune cells platelets and fibrin. However if by some chance the microorganism gets trapped under these cells, it will lead to development of clumps of tissue on the heart’s valves, which are called Vegetations.

These vegetations are dangerous because they aren’t firmly attached and can break off entering into the blood stream (Embolism). If a large enough embolus breaks off it can lead to  blockage of the smaller arteries depriving that specific area of blood. The damage of the blockage of blood depends on which area is has the blood supplied been altered, for example if it occurred in the  brain will cause stroke,  loss of sensation, partial blindness, even death.

Dental Management

Preventive antibiotics prior to a dental procedure are advised for patients with:

1. Artificial heart valves
2. A history of infective endocarditis
3. Certain specific, serious congenital heart conditions, including
   • unrepaired or incompletely repaired cyanotic congenital heart disease, including those with palliative shunts and conduits
   • A completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first six months after the procedure
   • Any repaired congenital heart defect with residual defect at the site or adjacent to the site of a prosthetic patch or a prosthetic device
4. A cardiac transplant that develops a problem in a heart valve.

Antibiotic Regimen

The Antibiotic Regimen for management of patients with Infective Endocarditis is as following:

• IV = Intra Venous / IM = Intra Muscular / g= Gram / mg = Milligram/     mg/kg = milligram per kilo
• Cephalosporins shouldnt be used with a person who has a history of anaphylaxis, angioedema or urticaria with penicillins or ampicillin.
• Table Courtesy  American Heart Association and American Dental Association.
  • Guide lines are from The Journal of the American Dental Association January 2008 vol. 139 no. suppl 1 3S-24S

Images Courtesy of Wikipedia: http://en.wikipedia.org/wiki/Infective_endocarditis