McNamara N, Narroway H, Williams M Contemporary outcomes of continuous-flow left ventricular assist devices-a systematic review. Ann Cardiothorac Surg. 2021; 10:186-208 https://doi.org/10.21037/acs-2021-cfmcs-35
Little JW, Rhodus NL Dental management of the heart transplant patient. Gen Dent. 1992; 40:126-131
Pávek V, Bígl P Stomatologické osetrování nemocných pred transplantací srdce a po ní [Dental treatment of patients before and after transplantation of the heart].: Czech; 1988
Cao Y, Chen X, Jia Y Oral health status of adult heart transplant recipients in China: a cross-sectional study. Medicine (Baltimore). 2018; 97 https://doi.org/10.1097/MD.0000000000012508
Habib G, Lancellotti P, Antunes MJ 2015 ESC Guidelines for the management of infective endocarditis: The Task Force for the Management of Infective Endocarditis of the European Society of Cardiology (ESC). Endorsed by: European Association for Cardio-Thoracic Surgery (EACTS), the European Association of Nuclear Medicine (EANM). Eur Heart J. 2015; 36:3075-3128 https://doi.org/10.1093/eurheartj/ehv319
Albert N, Trochelman K, Li J, Lin S Signs and symptoms of heart failure: are you asking the right questions?. Am J Crit Care. 2010; 19:443-452 https://doi.org/10.4037/ajcc2009314
Meechan JG, Parry G, Rattray DT, Thomason JM Effects of dental local anaesthetics in cardiac transplant recipients. Br Dent J. 2002; 192:161-13 https://doi.org/10.1038/sj.bdj.4801323
Craig D, Boyle C Practical Conscious Sedation.: Quintessence Publishing; 2019
Tobias JD, Leder M Procedural sedation: a review of sedative agents, monitoring, and management of complications. Saudi J Anaesth. 2011; 5:395-410 https://doi.org/10.4103/1658-354X.87270
Lindenfeld J, Miller GG, Shakar SF Drug therapy in the heart transplant recipient: part I: cardiac rejection and immunosuppressive drugs. Circulation. 2004; 110:3734-3740 https://doi.org/10.1161/01.CIR.0000149745.83186.89
Gibson N, Ferguson JW Steroid cover for dental patients on long-term steroid medication: proposed clinical guidelines based upon a critical review of the literature. Br Dent J. 2004; 197:681-685 https://doi.org/10.1038/sj.bdj.4811857
Ellis JS, Seymour RA, Taylor JJ, Thomason JM Prevalence of gingival overgrowth in transplant patients immunosuppressed with tacrolimus. J Clin Periodontol. 2004; 31:126-131 https://doi.org/10.1111/j.0303-6979.2004.00459.x
Montebugnoli L, Bernardi F, Magelli C Cyclosporin-A-induced gingival overgrowth in heart transplant patients. A cross-sectional study. J Clin Periodontol. 1996; 23:868-872 https://doi.org/10.1111/j.1600-051x.1996.tb00625.x
Montebugnoli L, Servidio D, Bernardi F The rôle of time in reducing gingival overgrowth in heart-transplanted patients following cyclosporin therapy. J Clin Periodontol. 2000; 27:611-614 https://doi.org/10.1034/j.1600-051x.2000.027008611.x
Swami AC, Kumar A, Rupal S, Lata S Anaesthesia for non-cardiac surgery in a cardiac transplant recipient. Indian J Anaesth. 2011; 55:405-407 https://doi.org/10.4103/0019-5049.84849
Roca J, Cruz Caturla M, Hjemdahl P Effects of adrenaline on ventricular function and coronary haemodynamics in relation to catecholamine handling in transplanted human hearts. Eur Heart J. 1993; 14:474-483 https://doi.org/10.1093/eurheartj/14.4.474
Ranèiæ NK, Vaviæ NN, Kovaèeviæ AM Drug–drug interactions of tacrolimus. Hospital Pharmacology-International Multidisciplinary Journal. 2015; 2:291-296 https://doi.org/10.5937/hpimj1503291R
Saklad M Grading of patients for surgical procedures. Anesthesiology. 1941; 2:281-284
White PD, Myers MM The classificationof cardiac diagnosis. JAMA. 1921; 77:1414-1415
Assistant Professor and Consultant of Conscious Sedation and Special Care Dentistry, Department of Basic and Clinical Oral Science, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia
Consultant and Honorary Senior Lecturer in Special Care Dentistry; Clinical Lead, Department of Sedation and Special Care Dentistry, Guy’s and St Thomas’ NHS Foundation Trust, London
The number of cardiac transplants carried out each year within the UK is increasing. With this rise in numbers, it is important that dental professionals are aware of both pre- and post-operative considerations for these patients. This paper considers the practical elements of managing these patients, outlining important aspects of history taking, treatment planning, and safe pain and anxiety management options.
CPD/Clinical Relevance:
The unilateral sagittal split osteotomy may present an alternative method for removing impacted mandibular third molar teeth in certain situations.
Article
Cardiac transplantation replaces a non-functioning heart with a healthy heart from a recently deceased donor.1 It is performed in those with end-stage heart failure or those with life threatening arrythmias when other medical or surgical treatments have failed.2
Annually, around 200 cardiac transplants are performed in the UK, with 5-year adult survival rates of approximately 71%.1
Those waiting for a cardiac transplant are assigned to either a super-urgent, urgent or non-urgent (routine) heart transplant list. The median waiting time on a non-urgent list is 2189 days, on an urgent list is 37 days, and on a super-urgent list it is 10 days.3 Those waiting for a donor may be offered a ventricular assist device (VAD). These are battery-operated pumps surgically implanted into the heart's left ventricle to partially or completely replace cardiac function. Although results are variable, 12-, 24- and 48-month survival rates with VADs are reported as 82%, 72% and 57%, respectively.4
The pre-cardiac transplant dental assessment
A comprehensive dental assessment is a fundamental part of the work-up towards cardiac transplant surgery. As patients are placed on high-dose immunosuppressive regimens in the post-transplant period,5,6 their risk of severe infection is increased. Any potential or actual sources of dental infection may therefore become acute, with potentially fatal consequences for the patient, including sepsis. Studies have demonstrated pre-cardiac transplant patients to have worse oral hygiene, higher DMFT scores, a higher prevalence of dental caries and a higher community periodontal index of treatment needs when compared to controls, further emphasizing the need for a dental assessment.7
The European Society of Cardiology recommends elimination of all potential sources of dental sepsis at least 2 weeks prior to the procedure.8 In some cases, this may not be possible, for example, if a heart becomes unexpectedly available, or if a patient who is very medically unwell cannot be transferred to dental services.
The pre-cardiac transplant dental assessment and treatment
Although a pre-cardiac transplant dental assessment is recommended, there is little guidance or detail on how this should be undertaken.
Medical history
Those being considered for cardiac transplantation, or those already on a list, will be ASA (American Society of Anesthesiologists) grade III–IV (see Table 1).
ASA
Description
I
Normal healthy patients
II
Mild systematic diseases
III
Severe systematic diseases that are limiting but not incapacitating
IV
Sever incapacitating systematic disease that is a constant threat to life
V
Not expected to live more than 24 hours
Questioning will help ascertain the stability of the patient's disease and their appropriateness for care in a primary versus secondary care setting.
Are you currently on a transplant list? If so, are you on an urgent or routine list?
Patients on an urgent or super-urgent list will have the most severe, unstable disease. Many will be inpatients in a specialist cardiac centre and, if safe for transfer, will be referred directly to specialist dental teams in either secondary or tertiary care. In some instances, transfer is not advisable. Assessments and, in rare cases, treatment may be carried out on wards; however, if not possible, treatment may be delayed until after surgery in the authors’ experience.
Those on routine lists and those being considered for cardiac transplantation are more likely to be outpatients. If treatment is required, the setting will depend on the amount and complexity of treatment needed, the level of dental anxiety, other comorbidities, and the severity of heart failure. This can be assessed with the following questions:
Do you get breathless/tired/dizzy?
The more marked these symptoms are, the worse the functional failure is likely to be. Cardiologists often describe class 1–4 symptoms of heart failure (see Table 2); Class 1 suggests no limitations to ordinary physical activity while class 4 indicates a complete inability to carry out physical activity without discomfort.
Class I
No limitations. Ordinary physical activity does not cause undue fatigue, dyspnoea or palpitations
Class II
Slight limitation of physical activity. Ordinary physical activity results in fatigue, palpitation, dyspnoea or angina
Class III
Marked limitation of physical activity. Less than ordinary physical activity leads to symptoms
Class IV
Unable to carry on any physical activity without discomfort. Symptoms of heart failure present at rest
Frequency of hospitalizations
Patients with frequent hospital admissions owing to the development of acute symptoms/dangerous arrythmias are likely to have more severe heart failure and more unstable disease.2
Do you have an implanted heart device?
Those requiring a ventricular assist device will often have the most severe heart failure as their own heart does not function sufficiently to sustain life. Once in situ, patients with these devices are arguably more stable than those without. While these patients may be assessed in general practice, the authors advise treatment within a secondary care setting.
Those at high risk of developing dangerous arrythmias may have an ICD (implantable cardioverter-defibrillator) in place. These devices, on detecting an abnormal rhythm, deliver either small rapid-pacing impulses or a larger electric shock to restore normal rhythm. The frequency of shocks and how recently they have occurred will allow dentists to risk assess how likely a shock will occur in the dental chair. Although no set guidance exists, the authors would suggest that anxious patients, and those who have had a shock within the preceding 12 months are best treated in a hospital setting.
Some patients may struggle to provide an accurate history, and correspondence with cardiac transplant teams will be required. Table 3 lists the seven cardiac transplant units within the UK.
City
Hospital
London
Great Ormond Street Hospital (Children) Royal Brompton and Harefield Hospital (Adults)
Cambridge
Royal Papworth Hospital
Birmingham
University Hospital Birmingham NHS Foundation Trust
Manchester
University Hospital of South Manchester
Newcastle
Freeman Hospital
Glasgow
Golden Jubilee National Hospital
The need for antibiotic cover must be considered on a case-by-case basis with the patient's cardiac team. Those with LVADs and ICDs are more susceptible to device-related infection. While antibiotic prophylaxis is not routinely recommended for these patients in the UK, many cardiology units will, in the context of a very unwell patient, still request this. Dental indemnity providers suggest that with the patient's consent, a discussion should be held with the patient's cardiologist regarding antibiotic prophylaxis and its likely benefit to the patient. These discussions, along with the indication for providing antibiotic cover, if agreed, should be clearly justified and documented in the patient's notes. The patient's primary cardiac disease, or previous cardiac surgeries may also warrant a need for antibiotic cover, with further guidelines on this provided in the SDCEP guidance on antimicrobial prophylaxis.9
Medications
Pre-cardiac transplant patients are likely to be on a combination of medications to reduce morbidity and control symptoms of heart failure. These medications, together with their potential oral manifestations and considerations are listed in Table 4.
Increased bleeding risk when carrying out invasive dental procedures. Dental care should be planned in accordance with SDCEP anticoagulation guidelines9
Examination
In end-stage heart failure, individuals may present with marked limitation of physical activity. Signs and symptoms include breathlessness, fatigue, hypoxia, angina/chest pain, cold intolerance, palpitations, frequent coughing, and arrhythmias.9Table 5 considers the dental impacts of these signs and symptoms and recommendations for management.
Breathlessness and hypoxia
Supine positions worsen breathlessness and hypoxia by increasing fluid accumulation in the lungs. A semi-supine position with pillows to raise the head is helpful. Supplementary oxygen via a nasal cannula or preventative inhalers, i.e. Ventolin, 2 puffs, may be recommended following liaison with the patient's cardiologist
Tiredness/fatigue
Shorter, morning appointments to avoid excessive fatigue and overworking of an already damaged heart should be considered
Angina/chest pain
Patients with end-stage heart failure may be at increased risk of angina episodes. The use of prophylactic GTN (2 puffs) prior to dental care may be beneficial and should be considered in collaboration with the patient's cardiologist
Cold intolerance
Patients with heart failure commonly have poor tolerance to cold; blankets should be considered in the dental surgery as required
Frequent coughing
Fluid accumulation in the lungs, and dry mouth related to polypharmacy, may lead to frequent coughing. Patient positioning, high volume suction, a staged treatment approach and the use of a rubber dam may all reduce this. The atraumatic restorative technique, which enables short appointments and avoids the use of handpieces, has been shown to be a well-accepted and effective treatment option for individuals who cannnot cope with conventional restorative treatment
Arrythmias
Arrhythmias occur when the heart beats too fast, too slow, or irregularly. They may be precipitated by stress owing to the increase in adrenaline. Dental anxiety should therefore be reduced, and consideration given to constant monitoring of the heart rate and oxygen saturations throughout
Dental treatment recommendations
The European Society of Cardiology (2015)8 suggests that any potential sources of dental sepsis should be removed, but there is no formal guidance on how this should be practically instituted, especially considering that some disease processes are chronic. Acute infections, teeth with large peri-apical areas, non-vital teeth, grossly carious teeth with a significant risk of pulpal involvement or those with advanced gum disease and mobility tend to be the most obvious candidates for urgent treatment. The decision on whether to maintain, restore or extract teeth will depend on a multitude of factors including dental symptoms, the tooth's prognosis and functionality, the patients’ oral risk status, their wishes and motivation, their medical status and ability to tolerate long appointments, and the urgency of the cardiac transplant. A patient with an acute infection on the urgent list may be better managed with an extraction rather than an extirpation, especially as dental care in the post-operative period must be delayed for at least 6 months. A patient on a non-urgent list who is relatively medically stable, can tolerate longer appointments and is motivated to retain teeth could be considered for more complex restorative treatment. Those on a non-urgent list should be closely followed up by a dental professional every 6–12 months depending on their risk status to ensure identification and treatment of new disease.10 Preventive advice, including OHI, is imperative to reduce the oral microbial burden, accepting that those with ongoing periodontal disease may not be dentally ‘fit’, but as dentally stable as possible for surgery.
Pain and anxiety management pre-cardiac transplant
Local anaesthesia
Local anaesthesia (LA) containing adrenaline for dental treatment in pre-cardiac transplant patients must be carefully considered. Adrenaline increases cardiac muscle contraction, heart rate and blood pressure. This increased workload in a poorly functioning heart can precipitate significant tachyarrthymias, potentially leading to fatal consequences.11 Despite these possible risks, adrenaline does have important advantages. As a vasoconstrictor, it delays systemic absorption of the LA, enabling a more potent effect with a longer duration. This reduces the patient's pain, which in turn limits the production of endogenous adrenaline. It is also beneficial to aid haemostasis during invasive treatments such as extraction, especially if patients are on anticoagulants or antiplatelets. In addition to LA containing a vasoconstrictor, these patients may require other local measures including a haemostatic dressing and sutures.
The American Heart Association and American Dental Association advise that adrenaline should not exceed 0.04 mg in those with end-stage heart failure.12 This equates to 1.5 cartridges of 2% lidocaine (with 1:80,000 adrenaline), two cartridges of 4% articaine (with 1:100,000 adrenaline) and four cartridges of 4% articaine (with 1:200,000 adrenaline). If further anaesthesia is required, a non-adrenaline containing LA such as 3% prilocaine with felypressin should be considered.
Conscious sedation
There is little literature on the prevalence of dental anxiety in adult cardiac pre-transplant recipients. However, these individuals may be more anxious owing to increased exposure to medical interventions.
Dental anxiety increases heart rate and blood pressure. To reduce these effects, conscious sedation techniques can be considered in a hospital setting.
Inhalation sedation (oxygen mixed with nitrous oxide) has anxiolytic and analgesic effects and is recommended for patients with mild to moderate levels of dental anxiety.13 Its effects on the cardiovascular system have been debated. While it is generally considered to have no or minimal effects, a potential dose-dependent negative depressant effect on myocardial contractility, and increases in pulmonary artery pressure have been reported.14 As pre-cardiac transplant recipients constitute the most severe cases of cardiovascular disease, liaison with the patients’ cardiologist is advisable as the maximum concentration of 70% nitrous oxide may need to be avoided.
Intravenous (IV) sedation with midazolam is useful for patients with moderate to severe dental anxiety, providing anxiolysis, amnesia and muscle relaxation.14 Midazolam reduces cardiac output and atrial pressure, hence leading to a reduction in the patient's blood pressure. While, in a fit and healthy patient, the baroreceptor reflex compensates for this reduction in blood pressure by increasing heart rate, this may not be the case in those with pre-existing severe heart failure.
Additionally, midazolam produces muscle relaxation and decreases the sensitivity of central chemoreceptors, thus producing respiratory depressant effects.14 For a patient with pre-existing hypoxia and breathlessness, this can be a significant problem.
An anesthetist-led sedation with cardiac monitoring in an appropriate hospital setting would be required if considering IV sedation.
General anaesthesia
General anaesthesia produces a considerable burden on the cardiovascular system and for patients with advanced heart failure, would be extremely high risk. A multidisciplinary approach including cardiac, anaesthetic and dental teams would be required if considering a dental general anaesthetic for these patients. It is rarely the preferred option.
Dental care in the post-transplant period
Immunosuppressive regimens
Rejection of a transplanted heart is a major cause of morbidity and mortality.15 It is therefore essential to achieve the correct balance of sufficient immunosuppression to avoid rejection, while minimizing the main sequalae of immunosuppression, namely infection and malignancies.
Immunosuppressive regimens may be either induction or maintenance regimens.16 Induction regimens, which provide intense early post-operative immunosuppression, are used for the first 2–3 weeks, resulting in significant depletion of T and B cells.16 During this period, prophylactic anti-bacterials, antifungals and antivirals are commonly used. Maintenance regimens are subsequently commenced and continued through life. These regimens vary between patients and cardiac centres; however, therapies consisting of a steroid, a calcineurin inhibitor (cyclosporin A, tacrolimus, sirolimus, everolimus) and an antimetabolite, for example mycophenolate mofetil or azathioprine, are most commonly used.16 Therapy doses are gradually reduced over time, with infection risk being highest within the first 3 months, and steroid therapy commonly being discontinued 6–12 months after heart transplantation.16
History taking
When planning care for post cardiac transplant recipients, the overall medical stability of the patient must be considered, as well as the potential risk of infection, malignancy, bleeding or steroid crisis caused by medications. The following questions may help the practitioner decide when and where to carry out dental treatment and the precautions necessary before and during treatment.
How long ago was your heart transplant and have there been any problems with rejection?
During the initial 6-month period post transplantation, dentistry should, as far as possible, be avoided. In the case of a dental emergency, close correspondence with the patient's cardiac team must be ensured, with any proposed dental care being carried out in a hospital setting.
Following this, elective dental care can be considered. The greater the length of time since a transplant was performed and the fewer problems there may have been with rejection, the lower the immunosuppressant dose and infection risk will be.
How often do you see your cardiac team?
A patient who sees their cardiac team more regularly (e.g. 1–3 monthly) is likely to be less stable than one who sees their team on a 6–12 monthly basis. Frequency of blood testing will also help ascertain how stable therapeutic levels for immunosuppressant drugs are. Very regular testing and review suggests poor stability and increased risk of rejection (if levels are too low), or increased risk of infection (if levels are too high)
Do you have any cardiac symptoms?
Dental professionals should question patients about any new cardiac signs or symptoms experienced. Fatigue, shortness of breath, fever, chills, dizziness, faintness, and swelling of the peripheries may all indicate rejection, with younger recipients, females, those of Afro Caribbean heritage, and those with a history of acute rejection being at greatest risk. If concerned, dental professionals should contact patients’ cardiac teams immediately.16
What medications have you been prescribed?
Immunosuppressants mainly work to reduce T and B cell activity, increasing infection and malignancy risk, and reducing wound healing. Azathioprine and mycophenolate mofetil can result in myelosuppression, with associated leukopenia, thrombocytopenia and anaemia.17 Patients may therefore have an increased risk of bleeding and anaemia. If invasive treatment is planned, an awareness of overall blood stability is essential, and a full blood count may need to be taken. Steroid cover will depend on whether patients have been taking high-dose steroids.
Corticosteroid cover
There is no national guidance for steroid cover within the UK; however, this is expected to be produced in the near future. At the current time, the authors suggest giving cover in the following scenarios:18
Patients who have received daily doses of >10 mg prednisolone or its equivalent in the previous 3 months for more than 3 weeks, or have received >40 mg prednisolone daily for longer than a week.
Patients undergoing a procedure that is very stressful for them.
Patients requiring care under GA.
The usual steroid dose can generally be doubled on the morning of the procedure and maintained for 24–48 hours after the procedure. In some circumstances, (usually under GA) 100 mg of hydrocortisone may need to be administered prior to treatment.19 As there is considerable variation between centres/providers, dental professionals should consider liaising with the patient's medical team.
Drug interactions
Antifungal agents such as topical miconazole as well as systemic fluconazole and itraconazole are known to raise levels of cyclosporin, tacrolimus and sirolimus.20 If required, antifungal doses may need to be reduced or substitutes used where possible.
Antibiotics, such as erythromycin, clarithromycin and metronidazole, and NSAIDs, including inbuprofen, can increase blood concentrations of cyclosporin and tacrolimus.19 They should be avoided, if possible, or only used following discussion with cardiac teams.
Oral complications and their management in the post-transplant period
A recent review that considered oral complications following cardiac transplantation found a significantly increased incidence of gingival hyperplasia, periodontal conditions, opportunistic infections (e.g. candida), and oral malignancies (including basal and squamous cell carcinomas) when compared to controls.20 This increased risk of disease is perhaps unsurprising, with most cases of gingival hyperplasia being specifically attributed to the drug cyclosporin A (CsA).21,22
Considering this increased risk of disease, the following recommendations are suggested.
Oral health recalls
Following the 6-month period post transplantation, oral health recalls should initially be carried out on a 3-monthly basis. This enables oral cancer screening, reinforcement of good oral hygiene, and early institution of treatment if needed. After 2 years, oral health recalls can be increased to 6 months.
Management of gingival hyperplasia
The prevalence of gingival hyperplasia has been reported to be as high as 67%.23 Dental care providers should liaise with a patient's cardiology team to consider substituting CsA with other drugs, such as tacrolimus, reported to produce less gingival hyperplasia.21 Reinforcement of oral hygiene and necessary periodontal treatment must be carried out. Montebugnoli et al reported that patients receiving periodontal treatment 6 months after transplantation had an improvement in periodontal indices 12 months after transplantation, with better gingival hyperplasia outcomes 36 months after transplantation.22,23
Prevention of infection
Early treatment of odontogenic infections is crucial to help avoid systemic spread in the immunosuppressed patient. It is particularly important to maintain a high index of suspicion as patients may not have classical signs and symptoms of infection.23
The FGDP antimicrobial prescribing guidelines suggest that for immunosuppressed patients, there is no evidence to support an increased risk of infection from dental procedures and advise against the use of antimicrobials for dental treatment.24 The authors nonetheless strongly recommend that due consideration, in collaboration with the patient's medical teams should be given to possible pre- or post-treatment antibiotic prophylaxis to avoid unpredictable dental infection, which might lead to sepsis in patients. The more recent the transplant and the higher the immunosuppression dose, the more likely it is required. Owing to the potential myelosuppressive effects of azathioprine/mycophenolate mofetil, bloods should be taken. If the neutrophil count is below <1.0/µl, antibiotic prophylaxis should be considered in conjunction with the medical transplant team.
Oral bleeding
Pre or post cardiac transplant, patients may take anticoagulants (i.e. warfarin), antiplatelets (i.e. aspirin), and/or novel anticoagulant agents. Additionally, post-transplant, immunosuppressive agents may produce myelosuppression increasing the risk of thrombocytopenia.
Dental care providers are strongly recommended to follow guidance published by the Scottish Dental Clinical Effectiveness Programme on the dental management of patients on anticoagulant or antiplatelet medications, which suggests liaison with the patient's medical team for more complex cases.25 While opinions vary, the authors suggest avoiding inferior alveolar nerve blocks at a platelet count of less than 30 × 109/l, and avoiding extractions if platelet counts are below 50 × 109/l. Local haemostatic measures and staged dental treatment approaches should be considered for those at higher risk of bleeding.
Pain and anxiety management post-cardiac transplant
The transplanted heart has no sympathetic, parasympathetic or sensory innervation.26 There is also a loss of vagal tone, resulting in an increased resting heart rate (usually between 82–110 bpm).29 Although the transplanted heart is a denervated organ, its intrinsic cardiac mechanisms are still preserved.27 If adrenaline is introduced, the heart will still respond to the direct effects of adrenaline on adrenergic receptors in its smooth muscle. These effects are not compensated by the parasympathetic system, resulting in exaggerated increases in heart rate and cardiac output.28 A clinical study comparing 20 post-cardiac transplant recipients and 10 healthy patients found that that there was a notable increase in the heart rates of the transplant patients who received adrenalinecontaining LA, when compared to healthy patients or those who received LA with felypressin.12 The authors recommended that dental care providers should respect the maximum doses, as suggested by the ADA/AHA (see section on LA pre-cardiac transplant recipients), and if these are insufficient for analgesia, epinephrine-free solutions such as 3% prilocaine with felypressin should be used.12 The advantage of felypressin is that it acts as a vasoconstrictor with its associated benefits with no changes to heart rate.
Conscious sedation and general anaesthesia
The transplanted heart is supersensitive to circulating catecholamines so anxiety management is important.
Both conscious sedation and GA use drugs that predominantly promote hypotension. Unlike the normal heart, which compensates for this via sympathetic input (increasing heart rate and contractility), a transplanted, denervated heart lacks the ability to respond to hypotension (or hypovolaemia) with reflex tachycardia. Instead, it responds to stress primarily by an increase in stroke volume in response to circulating catecholamines.29 An anaesthetist with knowledge of the pathophysiology of the transplanted heart, as well as the effects of various conscious sedation and GA drugs is required to assist in the management of these patients. Potential interactions between immunosuppressant and conscious sedation/anaesthetic drugs must also be considered, for example midazolam has an inhibitory effect on the liver enzymes that metabolize tacrolimus, increasing its concentration.29 Doses of midazolam may therefore need to be reduced and increased time left between increments. Myelosuppression caused by immunosuppressant drugs may also reduce haemoglobin, with suggestions to avoid both conscious sedation and GA below 10 g/dl haemoglobin.30 The implications of immunosuppression should also be considered, with oral tracheal intubation being preferred to nasotracheal intubation owing to the increased infection risk caused by nasal flora.30
Case study 1
A 34-year-old female was referred for a pre-transplant dental assessment. Medical history included dilated cardiomyopathy with an ICD in situ and decompensated heart failure.
She was an irregular dental attender due to dental anxiety and initially requested treatment under general anaesthesia. On examination, she required extraction of multiple extensively decayed molar teeth. Following discussion of the associated risks of dental treatment under GA, she agreed to treatment under inhalation sedation. The molar extractions were carried out over three appointments to minimize the use of local anaesthesia. While not strictly considered necessary in guidelines, the cardiac team requested antibiotic cover (3 g oral amoxicillin) which was given 1 hour pre-operatively to prevent infective endocarditis.
Case study 2
A 45-year-old male was referred to the special care dentistry clinic for dental assessment prior to inclusion on the urgent heart transplant list. His medical history included ischaemic cardiomyopathy, severe left ventricular systolic dysfunction and thrombus, and previous myocardial infarction. He was an inpatient at the time with decompensated heart failure requiring the use of an IV inotropic agent, milrinone. His medications included aspirin 75 mg once daily and enoxaparin 100 mg at 18:00. The patient attended the dental hospital in the morning accompanied by a specialist nurse escort. Dental assessment revealed a retained root of the UL5 which required extraction. Intravenous amoxicillin (1 g) was given at the start of dental treatment as prevention for infective endocarditis, 2 ml articaine with adrenaline (1:200K) local anaesthesia was given as infiltration, and local haemostatic measures employed to prevent post-operative bleeding in view of his antiplatelet and anticoagulant medication.
Case study 3
A 52-year-old male was referred 9 months post cardiac transplant for dental problems. He was reviewed every other month by his cardiac transplant team who considered him stable with no episodes of rejection. His medications included tacrolimus 75 mg twice daily, azathioprine 75 mg once daily and prednisolone 5 mg once daily. Examination revealed a carious UL4, a fractured LR6 and mild gingival hyperplasia. Restorative treatment was carried out with 4.4 ml lignocaine with adrenaline (1:80,000) For his ongoing dental care, 3-monthly supra- and subgingival scaling and 6-monthly dental recalls were arranged.
Conclusion
The number of patients undergoing cardiac transplant is likely to increase with better survival rates. As such, it is likely that general dental practitioners will come across more of these patients. Although most will require care in a secondary or tertiary care setting, the GDP plays an important role in prevention, as well as maintenance of oral health in the post-transplant period.
