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ISSN 2058-7813 Original Preference of North Carolina (USA) paediatric cardiologists for the American Heart Association guidelines for prevention of infectious endocarditis prior to invasive dental procedures Michael W. Roberts*, Jessica Y. Lee and Elman G. Frantz Department of Pediatric Dentistry, University of North Carolina School of Dentistry, Chapel Hill, USA. *Corresponding author: Michael W. Roberts [email protected] Editor approved: Pablo Varela-Centelles University of Santiago de Compostela, Spain Received: 20 October 2014 Revised: 03 December 2014 Accepted: 12 December 2014 Published: 18 December 2014 © 2014 Roberts et al; licensee Vernon Innovative Publishers. http://creativecommons.org/ licenses/by/4.0. Abstract Purpose: An updated Prevention of Infective Endocarditis guideline was published by the American Heart Association (AHA) in 2007. Our study examined whether paediatric cardiologists in North Carolina preferred the previous 1997 or the more recent 2007 guideline recommendations prior to invasive dental procedures. Methods: A cross-sectional study design was used to assess guideline preference among sixty-eight identified paediatric cardiologist in North Carolina (USA). The survey instrument contained questions relative to their preference for the AHA 1997 or 2007 guidelines, their age and sex, number of years in practice, practice profile and location. Results: Completed surveys were received from 32 paediatric cardiologists (4 females/28 males) for a response rate of 47%. There was no difference found between genders or in the number of years in practice in their prescribing preferences relative to antibiotic prophylaxis before invasive dental procedures. All but one (97%) preferred the 2007 guidelines but numerous exceptions were noted. Most of the responding paediatric cardiologists (27/32) were associated with a university/hospital, and practicing in an urban setting (19/32). Conclusions: An overwhelming majority of paediatric cardiologists in North Carolina who responded to our survey endorsed the 2007 AHA guidelines. However, exceptions were identified by some study respondents. Keywords: Infective endocarditis, cardiology, dental, antibiotic prophylaxis Introduction I nfective endocarditis (IE), formerly known as bacterial endocarditis, is fortunately a relatively uncommon life threatening disease. However, even though there have been advances in diagnosis, surgical techniques, and management of complications, high morbidity and mortality rates related to IE continues to exist in at-risk individuals. IE is the result of a complex interaction between blood-borne pathogens with matrix molecules and platelets at the site of endocardial cell damage. Turbulent blood flow produced by certain congenital or acquired heart disease predisposes the deposition of platelets and fibrin on the surface of the heart valve. This initially causes a thrombotic endocarditis on the cardiac valve surface and adherence of bacteria in the bloodstream to the thrombosis resulting in a vegetation and proliferation of the bacteria. Many of the clinical manifestations of IE are the result of the patient’s immune response to the microorganisms with pathogenic potential. Oral mucosal surfaces are covered by extensive and complex microflora including streptococcus viridans. A break in the mucosal surface permits many organisms to enter the blood stream. Only a few studies have been published that address the magnitude of bacteremia following a dental How to cite this article: Roberts, MW., Lee, JY. and Frantz, EG. (2014). Preference of North Carolina (USA) paediatric cardiologists for the American Heart Association guidelines for prevention of infectious endocarditis prior to invasive dental procedures. Archives of Oral and Dental Research, 1:4. Retrieved from http://www.vipoa.org/oraldent Archives of Oral and Dental Research procedure but it is relatively low [1-3]. There is no published the administration of antibiotics has the risk of increasing the evidence that the longer the bacteremia exists the greater the possibility of resistant strains of organisms developing. Indeed, an alarming number of resistant strains of streptococci viridians chance of IE. The first American Heart Association (AHA) guidelines were have emerged over time. In addition, the possibility of developing published in 1955 regarding prevention of rheumatic fever and an allergy to the antibiotic by the patient does exist [14]. The bacterial endocarditis through control of streptococcal infections recommendations regarding preventive antibiotic prophylaxis [4]. There have been numerous revisions and recommendations have over the years become complex often resulting in confusion published since [5-11]. In 1997, the AHA recommended among both health care providers and at-risk patients [15]. In 2007, the AHA published updated antibiotic prophylaxis antibiotic prophylaxis for prevention of bacterial endocarditis for both patients at high and moderate risk prior to certain guidelines for infective endocarditis that limited the prescription of antibiotics prior to defined invasive dental procedures and to dental procedure [12,13] Table 1. Since the 1997 AHA guidelines were published, numerous only patients at high risk [16,17] Table 1. Although there were studies have questioned the antibiotic recommendations differences, between the 1997 and the 2007 guidelines, both regarding prophylaxis prior to invasive dental procedures. recommended antibiotic prophylaxis for at-risk patients prior Authorities have noted that most incidences of IE were the to all dental procedures that involve manipulation of gingival or result of bacteremia occurring from routine daily activities (i.e., the periapical region of teeth, or perforation of the oral mucosa. tooth brushing) and not the result of an invasive medical/dental However, the AHA 2007 guidelines were considerably more procedure. Previous recommendations regarding antibiotic limiting than the association’s earlier versions. To make substantial changes in the recommendations prophylaxis were based primarily on what appeared to be a reasonable attempt to avoid a life-threating infection. However, regarding whether antibiotic prophylaxis was indicated prior to dental procedures in IE at-risk patients posed certain risks and potential consequences. These included reversing longTable 1. Cardiac conditions for which prophylaxis for dental standing expectations and practice patterns, causing confusion procedures is recommended. among patients with cardiac risk factors, making fewer patients 1997 AHA Guidelines eligible for prophylaxis, reducing malpractice claims related to IE infections [16], and would hopefully stimulate prospective High-risk category studies to better inform future guidelines. On the basis of the • Prosthetic cardiac valves, including bioprosthetic and homograft valves 2007 guidelines, many fewer patients are recommended for IE prophylaxis prior to invasive dental procedures. • Previous bacterial endocarditis Previous investigations have focused on physicians’ prefer• Complex cyanotic congenital heart disease (e.g., single ventricle states, transposition of the great arteries, ences to changes in clinical practice guidelines but none have tetralogy of Fallot) examined this in the context of the AHA guideline changes • Surgically constructed systemic pulmonary shunts or conduits regarding IE antibiotic prophylaxis. The risk for IE associated Moderate-risk category with a dental procedure in a patient with underlying cardiac • Most other congenital cardiac malformations (other than above condition is at best an estimate, but has been suggested to be and below) 1:95,000-1.1 million depending upon the cardiac condition • Acquired valvar dysfunction (e.g., rheumatic heart disease) [17-19]. Anecdotal information has suggested that not all pae• Hypertrophic cardiomyopathy diatric cardiologists agreed with the 2007 AHA changes in the guidelines regarding IE prophylaxis. The purpose of this study • Mitral valve prolapse with valvar regurgitation and/or thickened leaflets was to assess the IE prophylaxis preference prior to invasive 2007 AHA Guidelines dental procedures among a group of paediatric cardiologists in the United States (US). • Prosthetic cardiac valve • Previous infective endocarditis • Congenital heart disease (CHD) • Unrepaired cyanotic CHD, including palliative shunts and conduits • 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 • Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization) • Cardiac transplantation recipients who develop cardiac valvulopathy Roberts et al. 2014 Methods This survey was targeted toward paediatric cardiologists in North Carolina (USA) to determine their preferred practice in prescribing antibiotic prophylaxis prior to dental procedures for patients at risk for IE. No identifying patient information was requested. The names of paediatric cardiologists practicing in North Carolina were obtained from the North Carolina Medical Board, American Board of Pediatrics and by internet search. Prior to data collection, the development of a survey instrument was completed in two phases: 1) guideline review and 2) expert panel review. The expert panel consisted of two 2 Archives of Oral and Dental Research paediatric dentists, one of whom is an expert in survey design and a paediatric cardiologist. The data collection followed a three step process. The survey, along with a self-addressed envelope, was mailed to the 68 identified paediatric cardiologists (13 females and 55 males) Table 2. The name of the paediatric cardiologist who completed the survey was not linked to the survey once it was returned. A second copy of the survey was sent to those who did not respond to the first solicitation or redirected if the first mailing was returned as undeliverable. If no response was received from these two mailings, the nonresponding paediatric cardiologist was phoned by a member of the study in attempt to gather the information requested on the survey. The ages of the cardiologists and their years in practice were obtained in order that maturity and experience could be assessed as potential confounding factors in guideline preference. The primary outcome measure was practice preferences among a group of paediatric cardiologists. The Wilcoxon Rank Sum Test was used to evaluate the response data. This study was approved by the University of North Carolina IRB #13-2949, dated September 23, 2013. Results Completed surveys were returned by 32 paediatric cardiologists (4 females/28 males) for a response rate of 47%. The response rate for females was 31% and 51% for males. Practice setting and description are presented in Table 3. Nineteen paediatric cardiologists reported to have an urban practice, 9 suburban and 4 rural. Twenty-seven of the responders practiced in a university/ hospital setting. The remaining reported private/community practices. Neither age nor years in practice were significantly different for male and female respondents (Wilcoxon Rank Sum test: p=0.21 for age and years of practice) Table 4. When the paediatric cardiologists were asked whether they preferred the 1997 or the 2007 AHA guideline, an overwhelming 97% (all but one) preferred the 2007 version Table 5. However, a number of the respondents did report practice exceptions. A list of these exceptions is displayed in Table 6. Discussion This is the first study to examine the preferences of paediatric cardiologists in the United States since the 2007 changes in the AHA guidelines for infective endocarditis antibiotic prophylaxis. Interestingly, the National Institute for Health and Care Excellence (NICE) published guidelines in 2008 in the United Kingdom (UK) that recommended complete cessation of antibiotic prophylaxis for prevention of IE [20]. However, the European Society of Cardiology continued to recommend antibiotic prophylaxis prior to invasive dental procedures for high-risk patients [21]. Nevertheless, similar investigations on the preference of the Table 2. Survey instrument. Please circle or write your answer to the following: 1. ____ Check here if you do not practice pediatric cardiology in North Carolina. Do not complete the survey but do return it in the enclosed envelope. 2. For your at risk cardiac patients, which one of the above guidelines (1997 or 2007) do you prefer to follow for preventative antibiotic prophylaxis prior to your patients having and invasive dental procedure? 1997 2007 No preference 3. If you prefer to follow the 1997 rather than the most recent 2007 antibiotic prophylaxis guidelines, why? Easier to understand and follow More comfortable with old guidelines Did not appreciate that there was a difference between the two guidelines Other: _____________________________________________________________ 4. Are there exceptions to your usual antibiotic prophylaxis recommendations? Yes No If yes, what are these exceptions: ________________________________________ 5. What is your age? ______ 6. What is your sex? Male ______ Female ______ 7. What is your practicing setting? Urban ______ Rural ______ Suburban ______ 8. How best to describe your practice? Private/community ______ University/hospital ______ 9. How many years have you practiced as a pediatric cardiologist? ______ Roberts et al. 2014 3 Archives of Oral and Dental Research Table 3. Practice setting and description. Practice setting N Rural Suburban Urban Females 4 1 0 3 Males 28 3 9 16 Practice description N Private/ Community Females 4 0 Males 28 5 University/ Hospital 4 23 Table 4. Age and years in practice. Age in years N P25 Median P75 p-value Females 4 36.50 38.00 45.50 0.21 Males 28 40.00 45.50 52.00 -- Years practicing as a paediatric cardiologist N P25 Median P75 p-value Females 4 3.00 5.50 12.50 0.21 Males 28 5.00 12.00 20.00 -- P25, P75=percentiles; Wilcoxon Rank Sum test Table 5. AHA guideline preference. N 1997 Guideline 2007 Guideline Females 4 0 4 Males 28 1 27 Table 6. Exceptions given when not following the 2007 AHA guidelines. All single ventricle patients, even those with no fenestration are prescribed IE prophylaxis. (1) If I have assumed the patient’s care and the previous cardiologist, or dentist, recommended IE and the patient (parent) is reluctant to change this regimen, then occasionally I will continue IE prophylaxis even if they don’t meet the 2007 guidelines. (5) All patients with pacemaker/implantable cardioverter defibrillator. (1) Patients that are status/post tetralogy of Fallot repair if residual pulmonary stenosis/insufficiency exists and valve was manipulated. (1) All post-heart transplant patients. (1) If the patient’s paediatrician or dentist express concern if no antibiotics are prescribed. (1) Acyanotic complex congenital heart disease (i.e. Fontan without fenestration, baffle leaks). (1) If parent prefers/demands antibiotic prophylaxis. (4) Cyanotic heart defects even after repair and post repair surgery turbulence. (1) (X)=number of times cited by a responding paediatric cardiologist Roberts et al. 2014 NICE IE guidelines versus other guidelines amongst dentists, cardiologists and patient have since been address in the UK and Ireland [22-25]. The validity of any of the various conflicting recommendations has not been confirmed by a randomized clinical trial [26]. While previously, a retrospective study initially failed to show an increase over and above the rising trend of the incidence of IE in England two years on from the publication of the NICE guidelines, along with nearly a 79% reduction in the number of prophylactic antibiotic dental prescriptions, [27] a more recent, sophisticated analysis has reported an increased incidence above the rising trend of IE among high and lower risk patients in England, together with a 90% reduction in prescribed antibiotic prophylaxis prescriptions over the last five years [28]. Although this study has statistically confirmed a temporal association between the onset of NICE’s 2008 IE guidelines and the increase in the number of cases developing this disease, caution has been advocated before jumping to any conclusions on a cause and affect association [28]. Prospective randomized controlled studies have been therefore been advocated to address the issue, recognizing that failing to do so perpetuate the confusion among both patients and health providers [29]. The 1997 AHA guidelines regarding recommended antibiotic prophylaxis prior to invasive dental procedures were based on a few case control studies, clinical observations, and expert opinion. The rationale for the guidelines was to avoid a life threatening infection, where prevention would be preferable to treatment. The 2007 guidelines regarding antibiotic prophylaxis for identified cardiac issues prior to invasive dental procedures reflected changes from the 1997 version due to a lack of evidence to support some of the earlier recommendations [16,17]. However, there have been challenges to these conclusions. Some cardiologists believe that patients with cardiac issues (especially those with mitral valve prolapse) should be allowed to choose whether to take or not take antibiotics prior to an invasive dental procedure after being informed of the current (2007) recommendations until additional clinical evidence is available [30]. So far, earlier studies have not found an increased incidence of endocarditis since the 2007 AHA guidelines were introduced and would appear to support the more recent recommendations [31,32]. Other studies have reported that bacteraemia after tooth brushing is significantly greater in patients with poor oral hygiene and periodontal disease [33,34]. This would suggest that improving oral hygiene may be a more effective means of reducing the incidence of IE caused by oral bacteria than prescribing antibiotic prophylaxis prior to invasive dental procedures [35]. The results of our study should be considered in the light of some limitations. Because the survey was self-completed and submitted, responses may be susceptible to response bias. Another limitation of our study is the power of the study. Although a few trends were evident, the sample size was small. Despite these limitations, this study has several strengths including it being the first to report on this important topic 4 Archives of Oral and Dental Research of clinical relevance in the US. Only a little is known about 5. Rammelkamp, CH Jr., Breese, BB. And Griffeath, HI., et al. (1957). (Committee on Prevention of Rheumatic Fever and cardiologists’ preferences to the changes in the infective endoBacterial Endocarditis, American Heart Association). Prevention carditis recommendations prior to invasive dental procedures, of rheumatic fever and bacterial endocarditis through control of and almost nothing is known about recommendations in the streptococcal infections. Circulation, 15, 154-8. paediatric arena. 6. Committee on Prevention of Rheumatic Fever and Bacterial The child’s paediatric cardiologist is in the best position to Endocarditis, American Heart Association (1960). Prevention of appreciate the circumstances that could alter recommended Rheumatic fever and bacterial endocarditis through control of streptococcal infections. Circulation, 21, 151-5. antibiotic prophylaxis requirements. Therefore, it would appear 7. Wannamaker LW, Denny FW, Diehl A, Jawetz E, et al. (Committee prudent that a dentist contact the child’s paediatric cardiologist on Prevention of Rheumatic Fever and Bacterial Endocarditis, regarding recommendations for antibiotic prophylaxis prior to American Heart Association). Prevention of bacterial beginning an invasive dental procedure. endocarditis. Circulation 1965;31:953-4. 8. Rheumatic Fever Committee and the Committee on Congenital Conclusions Cardiac Defects (1972). American Heart Association. Prevention From the data collected in this present study, the following of bacterial endocarditis. Circulation, 46, S3-S6. conclusions can be made: 9. Kaplan, EL., Anthony, BF. And Bisno, A., et al. (1977). (Committee 1. An overwhelming majority of paediatric cardiologists in North on Rheumatic Fever and Bacterial Endocarditis, American Heart Association). Prevention of bacterial endocarditis. Circulation, 56, Carolina who responded to our survey endorsed the AHA 139A-43A. 2007 guidelines. However, there were exceptions identified 10.Shulman, ST., Amren, DP. And Bisno, AL., et al. (1984). by some study respondents. (Committee on Rheumatic Fever and Infective Endocarditis, 2. There was no difference between female and male paediatric American Heart Association). Prevention of bacterial cardiologists in their prescribing preferences relative to anendocarditis: a statement for health professionals by the tibiotic prophylaxis prior to dental procedures. Committee on Rheumatic Fever and Infective Endocarditis of the 3. There was no difference between female and male paediatric Council on Cardiovascular Disease in the Young. Circulation, 70, 1123A-27A. cardiologists in their age or the number of years they had 11. Dajani, A. S., Bisno, A. L., Chung, K. J., Durack, D. T., Freed, been practicing. M., Gerber, M. A., Karchmer, A. W., Millard, H. D., Rahimtoola, S., Shulman, S. T. and et al. (1990). Prevention of bacterial Competing interests endocarditis. Recommendations by the American Heart The authors declare that they have no competing interests. Association. JAMA, 264, 2919-22. 12. Dajani, A. S., Taubert, K. A., Wilson, W., Bolger, A. F., Bayer, A., Authors’ contributions Ferrieri, P., Gewitz, M. H., Shulman, S. T., Nouri, S., Newburger, J. All authors made significant contributions to this paper. W., Hutto, C., Pallasch, T. J., Gage, T. W., Levison, M. E., Peter, G. and Zuccaro, G., Jr. (1997). Prevention of bacterial endocarditis. 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