Heart of the matter

The Scottish Dental Clinical Effectiveness Programme has issued new advice on the use of antibiotics against infective endocarditis. In this article we look at what this means for the dental profession and hear the views of expert cardiologists on the clinical input to the process

Words: Dr Samantha Rutherford

In August 2018, the Scottish Dental Clinical Effectiveness Programme (SDCEP) issued new advice to support the implementation of National Institute for Health and Care Excellence (NICE) Clinical Guideline 64 (CG64) Prophylaxis Against Infective Endocarditis. The advice has been endorsed by NICE and is supported by a range of resources for practitioners and patients.

What is infective endocarditis?

Infective endocarditis (IE) is a rare infection of the endocardium (the inner lining of the heart), which has significant morbidity and mortality. The infection can be difficult to diagnose and particularly affects the heart valves. About 50 per cent of IE patients require corrective cardiac surgery, and fatality rates among IE patients are approximately 30 per cent.

What are the dental risk factors?

Patients with some predisposing cardiac conditions (see p28) are known to be at increased risk of IE, with most cases in this patient group caused by a bacterial infection originating from a transient bacteraemia. However, in about 50 per cent of new IE cases there is no known pre-existing cardiac disease. In the past, oral streptococci have been implicated in up to 45 per cent of IE cases. However, the proportion of IE cases associated with oral streptococci has fallen in recent years.

Previously, invasive dental procedures that cause high-grade bacteraemias were thought to be the main risk factor for IE of oral origin. This resulted in widespread use of antibiotic prophylaxis against IE in dentistry. However, the number of IE cases that originate from an invasive dental procedure appears to be small, and it is now believed that cumulative, low-grade bacteraemias, triggered by normal daily activities such as toothbrushing, flossing and chewing, are of greater significance. There is also a lack of evidence to support the use of antibiotic prophylaxis to prevent IE.

Invasive dental proceduresNon-invasive dental procedures
Placement of matrix bandsInfiltration or block local anaesthetic injections
Placement of Sub-gingival rubber dam clampsBPE Screening
Sub-gingival restorations including fixed prosthodonticsSupra-gingival scale and polish
Endodontic treatment before apical stop has been establishedSupra-gingival restorations
Preformed metal crown (PMC/SSCs)Supra-gingival orthodontic bands and separators
Full periodontal examinations (including pocket charting in diseased tissues)Removal of sutures
Root surface instrument/sub-gingival scalingRadiographs
Incision drainage of abscessPlacement or adjustment of orthodontic or removable prosthodontic appliances
Dental Extractions
Surgery involving elevation of a muco-periosteal flap or muco-gingival area
Placement of dental implants including temporary anchorage devices, mini-implants
Uncovering implant substructures

What is NICE Clinical Guideline 64 and why was it amended?

NICE Clinical Guideline 64 was issued in 2008 and provides recommendations on preventing IE in children, young people and adults. In a move away from previous practice, the guideline stated that “antibiotic prophylaxis against infective endocarditis is not recommended for people undergoing dental procedures”. Subsequently, prescribing practice in the UK changed, with a significant reduction in the provision of antibiotic prophylaxis against IE.

In 2015, the NICE guideline committee reviewed Clinical Guideline 64 in response to the publication of a study, which suggested that the incidence of IE in the UK might have been affected by the restriction of antibiotic prophylaxis. It found that there was no new evidence to determine whether antibiotic prophylaxis reduces the incidence of IE after interventional procedures, and the recommendation on antibiotic prophylaxis remained unchanged.

In 2016, NICE amended the recommendation to include the qualifying word ‘routinely’ to read: “Antibiotic prophylaxis against infective endocarditis is not recommended routinely for people undergoing dental procedures.”

NICE noted that this change was made to ensure that the recommendation was consistent with the obligations of healthcare professionals to involve patients in decisions about their care.

It was not intended that the amended recommendation would result in a change in practice as it remains true that the vast majority of patients at increased risk of infective endocarditis will not be prescribed prophylaxis. However, for a very small number of patients, it may be prudent to consider antibiotic prophylaxis (non-routine management), in consultation with the patient and their cardiologist or cardiac surgeon.

Why has the SDCEP advice been published?

There were concerns that the 2016 amendment to the NICE guideline did not define which individual patient should be considered for “non-routine” management. There was also a lack of information on appropriate antibiotic prophylaxis regimen(s) for use in a dental setting. SDCEP has developed advice to help the dental team implement the NICE recommendations.

The advice also aims to prevent variation in how Clinical Guideline 64 is implemented in practice.   

What does the SDCEP advice cover?

The advice is comprehensive and includes information and resources to support:

  • the identification of patients at increased risk, and those requiring further special consideration
  • routine and non-routine management
  • management of children with cardiac conditions
  • definition of invasive dental procedures
  • treatment of emergency patients
  • appropriate prescribing
  • communication with patients and obtaining valid consent.

 


Cardiology input critical to success

One notable aspect of the SDCEP approach to developing the new advice was its inclusion of all shades of experience and knowledge. The short-life working group included expert cardiologists, a move welcomed by members of that profession, writes Stewart McRobert. 

Michael Stewart, Consultant Cardiologist at South Tees Hospitals NHS Foundation Trust, regularly treats patients affected by endocarditis and was one of those in the working group. He said contact between cardiologists and dentists focuses mostly around practical clinical advice. “We can receive enquiries from dentists about individual patients – do we think the patient requires antibiotic prophylaxis? If so, what prophylaxis should be given? In the past, different cardiologists will have given slightly different advice. The guidance helps bring consistency and emphasises that, ultimately, it should be the patient’s decision.

“Unfortunately, there were occasions in the past where a patient, backed by his/her cardiologist, wanted to minimise risk through antibiotic prophylaxis but found their dentist reluctant to prescribe. The new SDCEP advice should help us avoid that potential conflict.”

John Chambers, Consultant Cardiologist and Professor of Clinical Cardiology at Guys’ and St Thomas’s NHS Foundation Trust, believes that clinical input to the SDCEP process was crucial and helped to ensure that the resulting guidance provided a pragmatic solution.

“The NICE guidance was confusing for patients, dentists and cardiologists. It was engendered by people who did not understand the clinical aspects of what they were pronouncing upon.”

In contrast, he emphasised, the SDCEP advice incorporates the considered opinions of clinicians and scientists involved in patient care. He does admit to one or two minor concerns about the new guidelines.

“They don’t indicate the level of risk in the ‘high-risk’ groups, that is those with prior endocarditis, artificial heart valves or uncorrected congenital disease. Those risks are very high – at the order of 300 times the average for prior endocarditis and 50 times for replacement heart valves. In addition, some dentists I have spoken to are concerned that dental scaling is not recognised as a high-risk procedure. That said, this is a solution that brings us in line with worldwide practice. It will help patients and those trying to apply guidance in a more clinical way.”

 


Patients at increased risk

NICE recommends that healthcare professionals should regard people with the following cardiac conditions as being at increased risk of developing infective endocarditis:

  • acquired valvular heart disease with stenosis or regurgitation
  • hypertrophic cardiomyopathy
  • previous infective endocarditis
  • structural congenital heart disease, including surgically corrected or palliated structural conditions, but excluding isolated atrial septal defect, fully repaired ventricular septal defect or fully repaired patent ductus arteriosus, and closure devices that are judged to be endothelialised
  • valve replacement.

While the vast majority of patients at increased risk of infective endocarditis (IE) will receive their dental treatment without antibiotic prophylaxis, a small sub-group will require special consideration for non-routine management:

  • patients with any prosthetic valve, including a transcatheter valve, or those in whom any prosthetic material was used for cardiac valve repair
  • patients with a previous episode of infective endocarditis
  • patients with congenital heart disease (CHD):
    • any type of cyanotic CHD
    • any type of CHD  repaired with a prosthetic material, whether placed surgically or by percutaneous techniques, up to six months after the procedure or lifelong if residual shunt or valvular regurgitation remains.

As well as being at increased risk of IE, these patients are also considered to be at particularly high risk of developing serious and potentially life-threatening complications. The identification and assessment of these patients will require liaison with their cardiology consultant, cardiac surgeon or the local cardiology centre. The number of patients requiring special consideration is likely to be small and therefore most dental practices would be expected to have very few of these individuals registered.

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Published: 1 December, 2018 at 18:32