3.5 Valvular Heart Disease

Question 1

What are rheumatic heart diseases?

Answer 1

Immune mimicry disease

An auto-antibody attacks cardiac tissue, mostly in heart valves (commonly mitral or left aortic)

Question 2

Abnormal heart valves are a conquence of rheumatic heart disease. What are some presentations of this?

Answer 2

1. Stenosis = narrowing of valves + failure to open completely
2. Insufficiency (regurgitation) = failure to close completely
3. Simultaneous stenosis + insufficiency

Question 3

What are possible consequences of rheumatic heart disease?

Answer 3

1. Heart valve abnormality = insufficent closure or opening
2. Arrhythmia = cardiac block, atrial/ventricular fibrillation
3. Heart murmur = abnormal heart sound
4. Cardiac hypertrophy or heart failure
5. Increased chance of infective endocarditis

Question 4

What is infective endocarditis?

Answer 4

Infection of heart tissue, mainly endocardium

Question 5

What is the cause of infective endocaridum?

Answer 5

1. Oral bacteria (streptococci) enter bloodstream though injured oral mucosa
2. Straphylococcus aureus enter skin
3. Bacteria proliferate in heart, causing septicemia + damage to heart tissue

Question 6

Who gets infective endocarditis?

Answer 6

Most susceptible patients have heart valve disease ot congenital heart diseases

Risk = dental procedures such as exo or subgingival scaling in susceptible patients

Question 7

What is the difference between bacteremia and septicemia?

Answer 7

Bacteremia = bacteria CONTAMINATION in blood vessels

Septicemia = bacteria PROLIFERATION in blood vessels + infection

Question 8

What are the signs + symptoms of infective endocarditis?

Answer 8

Pre-existing conditions for bacteria to vegetate

Fever + fatigue

New intra-cardiac murmur

Heart failure

Roth’s spots, petechiae, glomerulonephritis

Polyarthritis

Question 9

What measures in dentistry can be taken to help prevent infective endocarditis?

Answer 9

Prophylactic antibiotics in susceptible patients for dental procedures that breach oral mucosa

Drugs = amoxicillin 2mg 1 hr before OR clindamycin (if allergic to penicillin) 600 mg 1 hr before

Question 10

What patients are considered susceptible to infective endocarditis?

Answer 10

Patients with previous infective endocarditis experience

Rheumatic valve disease

Heart surgeries within 6 months

Congenital heart disease patients with cyanosis