Valvular Disease II- MS, MR, AS, AR Flashcards
AS causes in adults
congenital abnormalities, rheumatic fever, age-related calcific AS
pathophys of AS
impeded systolic flow through AV, compensations w/ LV concentric hypertrophy, reduced LV compliance, elevated diastolic LV pressure causes LA hypertrophy, eventual rise in pressures in LA and pulmonary circuit cause edema/HF Sx
3 main manifestations of AS
angina, exertional syncope, eventual dyspnea/ HF
these are in order of worsening prognosis
angina in AS
increased demand from hypertrophied LV and increased wall stress due to high systolic pressures
less supply because high LV diastolic pressure (less volume was ejected) reduces coronary perfusion
exertional syncope in AS
fixed, stenotic valve prevents augmentation of CO, combined w/ vasodilation of peripheral muscles from exercise causes decreased cerebral perfusion
dyspnea/HF and AS
progressive AS causes LV contractile dysfn, increased LV diastolic volume and pressure, increased LA and pulmonary pressure, pulmonary congestion/HF Sx
AS murmur
crescendo-decrescedo systolic, loudest at base, harsh and high pitched,
more severe AS= later peak of the murmur
when to Tx AS and hw
Tx w/ aortic valve replacement after development of Sx an evidence of LV dysfn (low EF or signs of dilation)
percutaneous balloon valvuloplasty not as effective, second line Tx
two subtypes of AR causes
valve leaflet abnormalities (bicuspid valve, endocarditis, rheumatic)
aortic root abnormalities (aneurysm, dissection, ectasia, syphilis)
3 factors influencing AR severity
size of regurg orifice, pressure gradient during diastole, duration of diastole
pathophys of AR
LV has volume and pressure overload, eccentric hypertrophy (dilation) compensation, increased compliance of LV
decreased aortic diastolic pressure and higher systolic pressure (more volume into aorta) causes widened pulse pressure
physical exam in AR
signs of widened pulse pressure, eg corrigan pulse: water hammer pulse in carotids
AR murmur
decrescendo diastolic murmur, increases w/ hand grip (higher SVR), heard best at 4th left intercostal space
can be systolic murmur from high systolic flow and second diastolic murmur (austin flint murmur) from vibration of leaflets and chrodae
angina and AR
decreased aortic diastolic pressure decreases coronary perfusion, reduced oxygen supply
increased LV size (eccentric hypertrophy) increases demand
chronic AR and HF
progressive remodeling of LV leads to systolic dysfn, then increased LA and pulmonary vascular pressure,then HF
chest xray of AR
cardiomegaly, esp LV and LA
Tx of chronic AR
depends on LV:
w/ normal fn and symptomatic- vasodilators (CCB, ACEi)
symptomatic or severe AR/ impaired EF- valve replacement
when to replace valve in AR
50/50 rule: EF is under 50% or LV end systolic dimension is over 50 mm
even w/o Sx!
etiology of MS
rheumatic fever, congential, calcific, endocarditis, tumors
major Sx of MS
dyspnea/HF, hemoptysis, A fib, stroke
MS causing dyspnea
high LA pressure leads to high pulm pressure, high pulm venous/capillary pressure= transudation of plasma into interstium and SOB
pathophys of MS
impaired filling of LV causes increased LA volume and pressure (eventually hypertrophy), reduced SV and CO from reduced preload
MS and hemoptysis
elevated pulm venous pressure causes opening of collateral channels b/w pulmonary and bronchial veins (to alleviate pressure), rupture of bronchial vein can cause blood to be coughed up
differentiate 2 forms of pulm HTN in MS
passive: LA pressure transferred to pulm system, pulm arteries facing higher resistance
active: medial hypertrophy and intimal fibrosis of pulm arterioles trying to reduce flow to the already backed up pulm system
right HF and MS
pulm HTN causes higher right heart pressures, RV hypertrophy and dilatation leads to right heart failure and the accompanying manifestations- JVP, hepatomegaly, peripheral edema, etc
A fib and MS
chronic pressure overload in LA causes LA enlargement, stretched conduction fibers more susceptible to reentry and A fib
stroke and MS
stagnant blood in large LA (esp w/ A fib) allows for thrombus formation and emboli to peripheral organs like the brain
palpation and auscultation of MS
RV tap palpable, from high RV pressure
can hear loud S1 w/ early MS, soft S1 later, Opening snap (shorter time b/w S2 and OS= more severe)
diastolic rumble- low frequency decrescendo murmur, accentuated before systole from LA contraction
describe the abnormal hemodynamics of MS
LA pressure normally equalizes to LV during diastole, in MS it remains elevated
Tx for MS
medical: diuretics for vascular congestion and betablockers/ anti coag for afib (beta blockers also increase diastole, allow for more foward flow across MV)
percutaneous balloon mitral valvuloplasty very effective w/ rheumatic MS, surgical valve replacement also works
causes of MR, 2 categories
primary: degenerative disorder of the valve, Tx is surgical correction
secondary: or functional MR, from underlying myocardial problem, Tx directed at cause
3 consequences of MR
elevated LA volume and pressure, reduction of CO, volume stress on LV
compensation for MR
increase in SV w/ frank starling
some factors that determine severity of MR
size of mitral orifice, systolic pressure gradient, SVR, LA compliance, duration of regurg
MR murmur
high pitched holosystolic, increases w/ hand grip, best heard at apex
can also hear S3
hemodynamics of MR
lots of extra volume in LA during systole
clinical pres in acute vs chronic MR
acute: pulmonary edema and high LA pressure
chronic: low CO (fatigue/weakness), LV dysfn (dyspnea, etc), right heart failure Sx (ascities, peripheral edema)
Tx for acute MR
IV diuretics for edema, vasodilators to augment forward CO, intra-aortic balloon pump
valve repair or replacement
Tx for chronic MR
vasodilators less useful, Tx the HTN or systolic dysfn
repair or replace valve
tricuspid stenosis
usually due to rheumatic fever, right heart failure w/ large a wave in JVP (high atrial pressure)
tricuspid regurg
usually functional following RV enlargement, Tx underlying cause or surgery
pulmonic stenosis
almost always congenital, only Sx when sever, balloon valvuloplasty for Tx
pulmonic regurg
lots of causes like severe pulm HTN or dilation of PA, IE, tet of fallot, trauma, rheumatic heart disease
Tx is surgical
