Heart conditions and dental treatment
DENTISTS are properly concerned to avoid cardiovascular collapse or deterioration in patients with pre-existing heart disease undergoing dental treatment, even though other forms of emotional or physical stress (or even exercise testing by physicians!) are likely to be dangerous.
The special risk of infective endocarditis arising from dental bacteremia is important, but ischemic heart disease and hypertension are much more common. It is good when patients volunteer a history of heart problems if there is one. But more importantly, by telling your dentist what medications you are currently taking, this can represent a more useful source of information.
The risk of harm from dental treatment generally arises more from inadequate control of anxiety and pain, than from the treatment itself.
‘Tender loving care’ is of prime importance, and a kind, confident and sympathetic approach is therapeutic in itself. Sedation with oral diazepam, or nitrous oxide and oxygen inhalation (relative analgesia) is safe, if needed.   I am particularly not in favour of intravenous agents. If necessary, they should be used very cautiously, and general anesthesia should be avoided. I do not believe anyone should be put to sleep to have one or more extractions, because the risk of general anaesthetic far outweighs the fear and anxiety of the procedure.
Local anesthesia, using lignocaine 2% with 1/80, 000 adrenaline, is very safe and effective. Adrenaline-free local anesthetic solutions are not effective. Noradrenalin is unsafe, and prilocaine with felypressin produces less reliable anesthesia than lignocaine with adrenaline.
Sensible management should include preventative dentistry and treatment planning to avoid lengthy or difficult procedures. It is important to ensure that patients have taken their normal medication on the day of their visit to the surgery.
Hypertensive patients do not bleed excessively after dental operations, and should simply be treated as described. Anti-coagulated patients are at risk of prolonged bleeding after oral surgery, and they should ideally be tested in a hospital prothrombin clinic to determine their current level of anticoagulation. The dentist must be available to provide control of bleeding by local methods in the first 24 hours, if required.
Patients with angina (a heart condition) should bring their anti-angina medication and keep it available during the dental appointment. Dental treatment in those with a recent heart attack (myocardial infarction) is probably best left until after six months, especially if general anesthesia is needed.
Ultrasonic scalers, electric pulp testers, diathermy or electrosurgery can upset pacemaker function, and this type of dental equipment should not be used for patients whose cardiac rhythm is controlled by a pacemaker.  I use most of these gadgets, so once again, it’s important that the dentist should be told if any pacemaker, etc is installed.
Patients who have had coronary artery bypass grafts do not risk infective endocarditis  (infection of the heart muscle) following dental surgery, and are usually fitted to withstand dental treatment after than they were before the heart operation.
Valvular heart disease is usually either congenital (you’re born with it), or arises from rheumatic carditis following rheumatic fever. It predisposes patients to infective endocarditis. The bacteremia (bacteria in your blood) that occurs when a tooth is extracted, or when the periodontium is damaged in scaling or flap surgery ect, may result in oral microorganisms settling upon and infecting minute, transient vegetations on the already damaged valves (infective endocarditis). Oral germs  involved are usually streptococci of the viridians group.
Other uncommon but important risk groups, such as patients who have had valve-replacement surgery, and those who have already suffered an attack of endocarditis are important not so much in having enhanced susceptibility, but in having a poor prognosis should they contract endocarditis. The hospital mortality for those 1 in 8 streptococcal cases associated with dentistry is quite low, but the figures conceal a considerable long-term morbidity. There is always the relevance of informing your dentist of prior heart surgery.