Flashcards in Lec 11 Valvular Heart Disease I Deck (47):
What is rheumatic fever?
- immuno response to group A strep pharyngitis 2-3 wks after initial infection
- cross-reactivity between strep antigen and structural glycoprotein
- leads to chronic rheumatic valvular heart disease = usually 10-30 yrs after ARF
What are the jones criteria for rheumatic fever?
- J= joints [polyarthritis]
- Heart =carditis
- N = Nodules [subcutaneous]
- E = erythema marginatum
- S = sydenham chorea
What is erythema marginatum?
pink rings on trunks and inner surfaces of limbs that come and go
What is sydenham chorea?
disorder of rapid uncoordinated jerking movements primarily of face, hands, feet
What heart signs associated with acute rheumatic fever?
- decreased LV contractility
- pericardial friction rub
- transient murmur of mitral or aortic regurgitation
- mid-diastolic murmur at cardiac apex
What is treatment for acute rheumatic fever?
- aspirin/corticosteroids to reduce inflammation
What is prophylaxis for pts with previous ARF?
low dose penicillin through early adulthood
b/c once you have ARF you are more susceptible to getting it again
What valve is most commonly affected in rheumatic fever?
mitral --> mitral stenosis
What kinds of valve disease can you get from rheumatic fever?
- most common mitral stenosis
- some get mitral stenosis + aortic stenosis or regurgitation
What is most common cause of mitral stenosis? less common?
other: congenital, infective endocarditis, mitral annular calcification
What is molecular mimicry?
mechanism by which antibodies to M protein of strep attack own human tissue in acute rheumatic fever
Which valves get affected preferentially in rheumatic fever?
mitral > aortic >> tricuspid
most common is mitral or mitral + aortic
What is early valve problem in rheumatic fever? later on?
early = mitral valve regurgitation
late = mitral stenosis
What is aschoff body?
sign of myocarditis in rheumatic fever = focus of chronic inflammation with fibrinoid material and giant cells and containing anitschkow cells
What are anitschkow cells?
macrophages with wavy caterpillar nuclei located in aschoff bodies = sign of myocarditis in rheumatic fever
What causes early death in acute rheumatic fever?
What causes friction rub in acute rheumatic fever?
How do you distinguish atrial stenosis from wear and tear vs atrial stenosis from rheumatic valve disease?
if from rheumatic valve disease will also have mitral stenosis + aorta will have fusion of commissures in rheumatic heart disease = fish mouth appearance
stenosis of just aorta without mitral involvement and no fusion = wear and tear
What are complications of aortic stenosis?
- concentric left ventricular hypertrophy
- angina and syncope with exercise
- microangiopathic hemolytic anemia
What kind of murmur with mitral stenosis?
- follows opening snap
- have delayed rumbling late diastolic murmur
What is significance of interval between S2 and opening snap?
shorter interval = more severe stenosis
What is opening snap?
after S2 loud sound of mitral opening due to initial rapid opening followed by abrupt stop in leaflet motion in diastole b/c of stenosis
What happens in mitral stenosis?
- obstruction of blood flow across mitral valve
- difficult to empty from LA to LV
- end up with high left atrial pressure [P in LA >> LV]
- valve area reduced from 4 in normal to 2 in MS
What are clinical manifestations of mitral stenosis?
- can be asymptomatic if less severe
- can have: dyspnea, reduced exercise tolerance, fatigue, signs of pulmonary congestion [b/c high LA pressure transmitted back to lungs]
What heart sounds in mitral stenosis?
- loud S1 = best heard at apex
- opening snap = follows S2, shorter S2 OS interval = more severe disease
- low pitched diastolic rumbling murmur following OS
What findings of mitral stenosis on EKG/CXR/ECHO?
EKG: LA enlargement, may have RV hypertrophy [b/c of pulm HTN] or AFib
CXR: LA enlargement, signs of pulm congestion, if pulm HTN: RV hypertrophy
Echo: assess thickness, mobility, area of MV
What is treatment for mitral stenosis?
- diuretics to treat vascular congestion
- if Afib: B blocker, Ca antagonist, digoxin
- prosthetic valves if continues; balloon mitral valvuloplasty
What are etiologies of mitral valve regurgitation?
- valve leaflets: rheumatic heart disease, infective endocarditis, myxomatous degeneration [mitral prolapse]
- mitral annulus: dilatation, calcification
- chordae tendinae: congenital, infective
- papillary muscle: CAD
- left ventricle dilation
What are some consequences of MR?
- high LA pressure/volume
- volume-stres on LV becuase regurgitate volume returns to LV in diastole along with normal venous return
What do you see in acute vs chronic MR?
acute: normal LA size and compliance --> high LA pressure --> high pulmonary venous pressure -->pulmonary congestion and edema
chronic: big LA size and compliance --> normal LA and pulmonary venous pressure --> decreased CO
What are symptoms of mitral regurgitation?
can be asymptomatic
- acute: symptoms of pulmonary edema: dyspnes, PND
- chronic: fatigue, weakness
- in severe chronic = symptoms of RV failure
What are physical exam findings of mitral regurgitation?
- holosytolic murmur loudest at apex and radiating to axilla
- increased sounds with expiration, handgrip, squatting
- may have S3 = increased volume returning to LV in early diastole
- in chronic: apical impulse laterally displaced toward axilla b/c LV enlarged
How do you manage acute MR?
- afterload reduction by: diuretics, nitrates
How do you manage chronic MR?
vasodilators for HTN, LV systolic dysfunction
What do you see in EKG of mitral regurgitation?
- LA enlargement
- LV hypertrophy
- can have AFib
What do you see in chest xray of acute/cronic MR?
acute = interstitial edema
chronic = cardiomegaly [LV/LA]
What do you see in cardiac cath/angio of mitral regurgitation?
large V wave on pulmonary capillary wedge pressure
What is mitral valve prolapse?
billowing/floppy mitral leaflets into left atrium during ventricular systole, sometimes accompanies by mitral regurgitation
- valve leafless enlarge and elastin matrix of leaflets replaced with loos myxomatous connective tissue
What is etiology of mitral valve prolapse?
- can be inherited autosomal dominant or associated w/ marfans, ehlers-danlos
What are symptoms of mitral valve prolapse?
may have chest pain or palpitations
What are signs of mitral valve prolapse?
- midsystolic click followed by late systolic murmur
- best heard at apex
- decreased sound with squatting and increased by valsalva standing and handgrip
What tests do you do in mitral valve prolapse?
echo to confirm diagnosis
What are some potential complications with mitral valve prolapse?
- rupture of chordae tendinae --> acute mitral regurg + pulm edema
- infective endocarditis
How do you differentiate mitral valve stenosis due to rheumatic vs other cause?
rheumatic = have subvalvular fibrosis/ disease
How do you classify severity of mitral valve stenosis based on area of the valve [in cm2]?
1.5-2 = mild
1-1.5 = moderate
< 1 = severe
What is the only time you get S3 without heart failure?
in chronic mitral regurgitation = b/c extra load of blood from LA --> LV creating a vibration
may get flow murmur in diastole as sign of severe mitral regurgitation