When a mother and father are given the news that their baby has a severe, congenital heart defect (CHD), they are given a lot of information that needs to be discussed again and again as the child ages. One of the areas that my son's cardiologists have been good at reviewing with us has been the need for taking medication in anticipation of dental procedures -- which is known as prophylaxis antibiotics by the doctors.
What are doctors worried about? A horrible, possibly life-threatening condition known as "infective endocarditis" is an infection of the endocardium (heart muscle) that usually involves the valves and adjacent structures and is caused by a wide variety of bacteria and fungi. Although infectious disease clinicians may be familiar with this disease, general internists may not have much exposure to this condition, therefore it behooves parents of children with congenital heart defects to understand and prevent this condition if at all possible. (See http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/infectious-disease/infective-endocarditis/ for more information, but be prepared; some of the photos are pretty graphic.)
Since infants aren't receiving dental cleanings, taking antibiotics before cleanings doesn't become an issue for many of us until our children have recovered from at least one open-heart surgery and in my son's case, it wasn't necessary until after his fenestrated Fontan (since his surgery was done at 9 months of age). The good news regarding that situation is that our CHD babies have time to heal from their cardiac surgery before worrying that something as mundane as a dental cleaning could cause an infection that could cause a hospitalization, or worse -- more surgery or even death.
Why should parents worry about whether or not their children need antibiotics before dental cleanings? The simple answer is because parents of babies with severe, congenital heart defects are dealing with a medical condition which transcends their hearts and has the chance to affect them in other non-cardiac areas as well. A prudent parent is always on watch against potential problems that could be prevented with something as benign as a dose of penicillin before a dental cleaning or some other procedure.
The American Heart Association has been very good at providing wallet cards for patients (or parents) which outlines the people who need to be aware of the guidelines to prevent infective endocarditis (http://www.heart.org/idc/groups/heart-public/@wcm/@hcm/documents/downloadable/ucm_307684.pdf) My son's cardiologist frequently asked Alex if he needed a new card for his wallet whenever he had his regular visit (every 6 months). What should perhaps cause us concern is that these guidelines are based on logic and not on quantifiable research. That is why I was so interested to read a study actually looking at cumulative incidence and predictors in CHILDREN with congenital heart disease (http://circ.ahajournals.org/content/128/13/1412.full.pdf+html). The reason there haven't been more studies like this is because of the enormity of the task in gathering the information needed to make statistics meaningful. Thankfully, the incidence of infective endocarditis is relatively small (between 2 and 6 cases per 100,000 person-years), but the incidence in patients with underlying valvular heart diseases is greater.
The study referenced above fascinated me because it looked at all of the patients in the Quebec CHD Database who were children 0-18 years of age between January 1, 1988 and March 31, 2010. The authors did a good job of explaining how the data was gathered and analyzed and even detailing possible flaws with the study. What was most interesting were the results:
They found that children most at risk for infective endocarditis were the following:
• children with cyanotic CHD lesions
• children with left-sided lesions
• children with endocardial cushion defects
• children recovering from open-heart surgery, especial during the 6-month postoperative period and in children 3 years of age and younger
This study confirmed the AHA guidelines for giving antibiotics before dental procedures or other surgical procedures but it found that the relaxed AHA guidelines (from 2008) may have left out children who suffered from some of the conditions above who had not had surgery, and especially the patients with left-sided lesions or endocardial cushion defects. My son suffers from left-sided heart lesions (hypoplastic left heart syndrome), and even though the AHA relaxed its guidelines in 2008, my son's cardiologists always insisted that Alex continue to take antibiotics prophylactically and I'm thankfully they did! This study shows that people like Alex are more at risk for developing infective endocarditis than other CHD children who don't have the conditions listed above.
We need more studies like the one done in Quebec. If we can get funding for the Congenital Hearts Future Act, then we will start to develop a database of information like the one that the Canadians can refer to and we will be able to gather information like that in this study here in the United States. The fact that this study questions some of the AHA Guidelines for prevention of infective endocarditis is indicative of the need for more research. Research like this is much easier to do if we have the data in a national database. Let's keep pushing for the United States Congress to provide funding for the Congenital Heart Futures Act so we can continue to modify the AHA guidelines when needed so our children, and aging population of adults with CHDs, won't be at risk for infective endocarditis.