NMF Professional Advisory Board Statement
Endocarditis Prophylaxis for People with Marfan Syndrome

Issued November 2007

In April 2007, the American Heart Association (AHA) revised its guidelines for antibiotic treatment at the time of dental procedures and other medical situations in which there is a high likelihood of bacteria entering the blood stream. In general, the AHA guidelines are the “gold standard” in the United States for how physicians and dentists should practice with respect to this important issue of preventing infections of heart valves (endocarditis). A major aspect of the revised guidelines is the recommendation that oral antibiotic therapy is no longer required at the time of dental work or other procedures expected to contaminate the bloodstream with bacteria for patients with mitral valve prolapse or other valve dysfunction, but is still recommended for those patients who have an artificial heart valve.  The basis for this decision was not the conclusion that risk of endocarditis is not present in this population at the time of such procedures, but rather that a cumulative risk is also present in association with other routine activities of daily living such as normal brushing and flossing of teeth and even chewing of food. In fact, it is considered that the cumulative risk of endocarditis during daily life activities is higher than that associated with a specific dental or other invasive procedure.  (See Box 2 below).  

The AHA continues to recommend antibiotic prophylaxis for specific subpopulations of individuals with valve dysfunction or intracardiac conduits who are deemed less capable of withstanding such infection, such as those with complex congenital heart disease or those with prosthetic heart valves or previous episodes of endocarditis  (See Box 3 below). Individuals with Marfan syndrome or other inherited connective tissue disorders are neither specifically included nor excluded from this list.
 
 The NMF Professional Advisory Board recognizes the importance of good oral health and routine dental evaluation for people with Marfan syndrome and related disorders.  We continue to stress that all patients who have had a composite graft repair, placement of an artificial valve or a history of infective endocarditis must receive antibiotics before dental work or other procedures expected to contaminate the bloodstream with bacteria.  At a minimum, the AHA guidelines should be applied.   In addition, the relevance of the recent modifications to Marfan patients with only mitral valve prolapse, prolapse with mitral regurgitation, or aortic regurgitation is unknown.  Clearly more studies are needed to address this important issue. In the interim, given the propensity of individuals with Marfan syndrome formultivalvular dysfunction, myxomatous valve changes, and other cardiovascular disease and/or systemic illness that can predispose to infection or hamper recovery from endocarditis, and given the low burden and risk associated with the use of antibiotics for endocarditis prophylaxis, the Professional Advisory Board (PAB) of the NMF finds a compelling argument for the continued use of antibiotics in people with Marfan syndrome and valve dysfunction that is consistent with the spirit of the recent modification of AHA guidelines. There are differences of opinion from the PAB as to whether all people with Marfan syndrome should receive SBE prophylaxis. Individuals with Marfan syndrome without valvular abnormality or with mild mitral valve prolapse without an obvious leak are at such low risk of endocarditis that prophylactic antibiotics are of little or no value. Each person with Marfan syndrome should consult with his or her cardiologist or cardiovascular surgeon to discuss this issue and for specific recommendations for their care with regards to whether or not antibiotic prophylaxis is appropriate for him/her.

The 2007 AHA guidelines recommendations are listed for your reference. Tables from the text of the AHA recommendations are listed below for your reference.

NMF Professional Advisory Board Chair
Dianna Milewicz, MD, Ph.D., University of Texas Houston Medical Center

NMF Endocarditis Prophylaxis Task Force
Joseph Coselli, M.D., Methodist Hospital and Baylor College of Medicine
Richard Devereux, M.D., New York Presbyterian - Weill Cornell Medical College
Alan Braverman, M.D., Washington University School of Medicine
Hal Dietz, M.D., Johns Hopkins School of Medicine
Heidi Connolly, MD,  Mayo Clinic

Box 2:  Reasons for the revision of the infective endocarditis guidelines.

Box 3:  Cardiac conditions associated with the highest risk of poor outcomes if endocarditis would develop and therefore for which antibiotic prophylaxis has been recommended.

Box 5 :  Summary of the changes in Antibiotic Recommendations from the AHA.

Tables from the AHA Guidelines as published in:  J Am Dent Assoc, Vol 138, No 6, 739-760, 2007

2007 American Heart Association Guidelines
Prophylactic Regimens for Dental, Oral, Respiratory Tract, or Esophageal Procedures. (Follow-up dose no longer recommended.) Total children's dose should not exceed adult dose.

I. Standard general prophylaxis for patients at risk:
Amoxicillin: Adults, 2.0 g (children, 50 mg/kg) given orally one hour before procedure.

II. Unable to take oral medications:
Ampicillin: Adults, 2.0 g (children, 50 mg/kg) given IM or IV within 30 minutes before procedure.

III. Amoxicillin/ampicillin/penicillin-allergic patients:
Clindamycin: Adults, 600 mg (children, 20 mg/kg) given orally one hour before procedure.
-OR-
Cephalexin* or Cefadroxil*: Adults, 2.0 g (children, 50 mg/kg) orally one hour before procedure.
-OR-
Azithromycin or Clarithromycin: Adults, 500 mg (children, 15 mg/kg) orally one hour before procedure.

IV. Amoxicillin/ampicillin/penicillin-allergic patients unable to take oral medications:
Clindamycin: Adults, 600 mg (children, 20 mg/kg) IV within 30 minutes before procedure.
-OR-
Cefazolin: Adults, 1.0 g (children, 25 mg/kg) IM or IV within 30 minutes before procedure.

*Cephalosporins should not be used in patients with immediate-type hypersensitivity reaction to penicillins. 

NOTE: For patients already taking an antibiotic, or for other special situations, please refer to the full scientific statement on the prevention of bacterial endocarditis:  Prevention of infective endocarditis: Guidelines from the American Heart Association on-line at
http://circ.ahajournals.org/cgi/reprint/CIRCULATIONAHA.106.183095v1
and
http://circ.ahajournals.org/cgi/content/full/circulationaha;116/15/e376