CVS - diseases of the valves

Question 1

stenosis vs insufficiency (regurgitation)

Answer 1

stenosis: valve fails to open completely - forward flow
regurgitation: valve doesnt close properly - reverse flow

Question 2

causes of stenosis

Answer 2

PCC

• post inflammatory scarring - RHD*
• calcification - calcific aortic stenosis*
• congenital

Question 3

causes of regurg

Answer 3

P-DDI

• post-inflammatory scarring
• developmental: marfan (weaker tissue cells - cause valve to stretch and cause abnormal valvular fn)
• degenerative: mitral valve prolapse*
• infection: infectious endocarditis*, syphillis

Question 4

abnormal valves

Answer 4

• congenital bicuspid aortic valve (usually its a tricuspid)
• RHD damaged
• prosthetic valves

Question 5

aortic valve calcification

Answer 5

most common valvular abnormally

causes aortic stenosis

Question 6

mitral valve prolapse

Answer 6

ballooning of valvular cusps
more in young women
causes mitral regurgitation
degenerative disease - regurg

Question 7

RHD - rheumatic fever

Answer 7

inflammatory disease - autoimmune
caused by group A strep (strep pyogenes) - immune response towards it end up cross reacting w/ host proteins
** Aschoff bodies:
- T lymphocytes, plasma cells, aschoff giant cells, activated macrophage (w/ long nucleus like caterpillar)
Vegetations

causes damage to valves - affects left sided valves more: esp mitral valve

Question 8

Infective endocarditis

Answer 8

microbial infection (strep viridans/s.aureus/ -> formation of vegetations -> tissue destruction

• acute
• subacute

Question 9

acute infective endocarditis

Answer 9

virus directly invades the valve, causing rapid destruction

• affects IV drug addicts, open heart surgery, septicemia
• strep viridans

IV drug addicts: most likely s.aureus from skin entering the bloodstream causing bacteremia -> directly infect and damage healthy valves

Question 10

subacute IE

Answer 10

gradual, but harmful
most likely strep viridans

Streptococcal antigens (M protein) cross-react with self antigens expressed on heart valves -> type 2 hypersensitivity (molecular mimicry)

Question 11

cause of IE

Answer 11

• abnormal valves
• microorganisms in the blood:
  dental/surgeries, IV drug needles, breaks in epithelium of gut/oral cavity/skin
• staph aureus

Question 12

IE complications

Answer 12

local:

• valve rupture
• myocardial ring abscess
• suppurative endocarditis

distant:

• septic emboli (embolism that dislodge and travel distally)
• immune complex (eg. glomerulonephritis)

Question 13

non-bacterial thrombotic endocarditis (NBTE) causes

Answer 13

• hypercoagulability of blood
• platelet-rich vegetations on valves
• debilitated pts: decreased immunity

Question 14

valvular disease complications

Answer 14

• heart: LVH, myocardial ischemia, HF, arrhythmia

- lungs: pulmonary HTN, congestion

Question 15

causes of chronic valvular diseases

Answer 15

• IE
• mitral valve prolapse
• RHD