Valve disease and endocarditis Flashcards
What are the 2 left heart valves called?
- Aortic, Mitral
What are the 2 right heart valves called?
- Pulmonary, Tricuspid
Which side of heart valves most commonly fail?
- Left side valves:
- Aortic stenosis & incompetence
- Mitral stenosis and incompetence
What is used to treat valve failure problems?
- Prosthetic valves
What is Valve stenosis?
- Stenosis is a term for a valve that doesn’t open properly. The flaps of the valve thicken, stiffen or fuse together. As a result the valve cannot fully open
Who are heart valve failures commonly affected by? (2 points)
- Elderly
- Downs
What are the common symptoms of heart valve failure?
- Rarely any symptoms - undiagnosed
What is an example of a congenital abnormality of a heart valve?
- Bicuspid Aortic Valve
- (normal is a tricuspid aortic valve)
What are possible causes of heart disease? (4 points)
- Congenital abnormality
- Myocardial infarction (papillary muscle rupture)
- Rheumatic fever (immunological reaction to streptococci)
- Dilatation of the aortic root (syphilis, aneurysm formation)
Is taking an ultrasound of the heart a good investigation into valve disease?
- Yes
What are the 2 main oprti9ons for valve replacement?
- Mechanical valve
- Porcine (pig) valve
What is a benefit of being given a pig valve?
- Pic valve is roughly the same size and has a natural collagen reflex so blood will not stick to them anymore than it would in a pig
What is a disadvantage of a pig valve?
- It will only last about 10 years
- So good for the young and the old - choosing not to put a metal valve in can be good for people at extremes of life
- Every time you replace a valve there is a chance of the patient dying so want to do it as little as possible
What is a disadvantage of giving a mechanical valve?
- As it is metal blood will stick to it and clot so the patient ha s to be on anticoagulants
What is there a risk of in patients who have had a valve replacement?
Risk of endocarditis - infection of the heart muscles layer which can happen with bacteria such as streptococci which can be found in the mouth
There is a risk of endocarditis following a valve replacement. How can you minimise the risk? (4 points)
- Maximise oral health
- Be sensitive to patient and surgeon needs
- Be aware or international disagreement in this area
- Sometimes antibiotics are given - case by case
What are the 2 different types of mechanical valve?
- One that flips open and shut
- One with a little ball - the ball moves with different pressures
How can you tell if a patient has a mechanical heart valve or a pig valve?
- Every time a mechanical valve opens and shuts it makes a noise
- So if you have a patient and it doesn’t tick then it is a pic valve and if it is a mechanical valve it will tick
What is a congenital heart defect?
- Failures in the normal development and fusion of the embryonic heart
Congenital heart defects are often undetected and asymptomatic. What are 4 examples of these?
- ATRIAL septal defect
- VENTRICULAR septal defect
- Patent ductus arteriosus
- Great vessel malformations
What is cyanosis?
- A physical sign causing bluish discolouration of the skin and mucous membranes. Cyanosis is caused by a lack of oxygen in the blood. It is also associated with cold temperatures, HF, lung diseases and smothering. It is seen in infants as a result of heart defects
What causes central cyanosis?
- Congenital heart defects
What causes peripheral cyanosis?
- Cold environment
What are the figures that show someone has cyanosis?
- When there is 5g/dl or more of deoxygenated Hb in the blood
What is central cyanosis?
- Cyanosis throughout the body not just in the peripheral tissues
- Where patients core tissues are cyanosed
What is a common sign of someone with cyanosis?
- Finger clubbing
- Swelling of the terminal tissues of the fingers
How could you investigate a congenital heart defect?
- Using an ultrasound scan
What is an atrial septal defect?
- A problem going from one atria to the other (hole in wall between them)
- Takes oxygenated blood from the lungs and squeezes some blood into the right atrium which pumps blood round the lungs again
Why may there be an enlarged atria when there is an atrial septal defect?
- As the atria is doing more work as it has to pump more blood than normal
What is a ventricular septal defect?
- VSD is a hole in the wall separating the 2 ventricles (lower chambers) of the heart.
- In normal development, the wall between the chambers closes before the fetus is born, so that by birth, oxygen-rich blood is kept from mixing with the oxygen-poor blood. When the hole does not close, it may cause higher pressure in the heart or reduced oxygen to the body
What is co-arctation of the aorta?
- A congenital narrowing of the aorta
What is patent ductus arteriosus?
- A heart problem which affects some babies soon after birth. In PDA, abnormal blood flow occurs between 2 of the major arteries connected to the heart. These arteries are the aorta and the pulmonary artery
What is infectious endocarditis?
- Infection of the endocardium - usually on the valves
- Microbial colonisation of thrombi on endocardial surface abnormalities
How many new cases of infective endocarditis are there per year in the UK and how many of these result in death?
- 1400 new cases
- 200 deaths
- 50% of patients are over 50
What are the predisposing factors of infective endocarditis? (3 points)
- Often NO predisposing factors
- Rheumatic fever less common
- Prosthetic valves more common
What signs and symptoms can help to diagnose infective endocarditis? (7 points)
- Fever (90%)
- Heart murmur (85%)
- Embolic pneumonia (>50%)
- Skin manifestations e.g. olser nodes, splinter haemorrhages(18-50%)
- Splenomegaly (20-57%)
- Septic complications e.g. pneumonia, meningitis (20%)
- Mycotic (infective) aneurysm (20%)
What are 3 possible organisms involved in infective endocarditis?
- Streptococci
- Staphylococci
- Fungi
What prolonged antibiotic treatment may be needed for someone with infective endocarditis? (2 points)
- 4+ weeks of bacteriocidal treatment
- Often combinations of drugs
Can infective endocarditis cause cardiac valve damage?
- Yes, can cause valve dysfunction which can result in urgent valve replacement needed
How can you prevent infective endocarditis in the dental setting? (3 points)
- Only possible if ‘at risk’ patients are identified via medical history or prominent identification in case records
- Would avoid risk procedures
- May use antibiotic prophylaxis when needed
If treating a patient for prevention of infective endocarditis in the dental setting what medication would you give them?
- 3g of Amoxicillin orally 1 hour before the procedure - even if used recently
- UNLESS ALLERGIC
- If allergic would give 0.6g of Clindamycin (higher ADA risk - ONLY use if penicillin allergic)
