Prosthetic valves and VADs Flashcards
Echo assessment of prosthetic valves
2d- type of valve, well seated, leaflets moving, any masses
color doppler- antegrade flow, washing jets, pathologic regurg, paravalvular leak
hemodynamics - velocity, gradients, area calculation
look for colateral damage
anatomic vs antianatomic mitral mechanical valve
anatomic- leaflets in same orientation as native valve
anti-antatomic- leaflets perpendicular (favors symmetric blood flow)
Will protamine fix paravalvular leaks
small low velocity leaks typically resolve
DVI for prosthetic aortic valve
normally .35-.5
medtronic hall tilting disc regurgitant jet
large central, small peripheral
st jude washing jets
directed inward
on x washing jets
directed away (divergent)
Differential for high gradient after replacement
bad measurement - over tracing, MR contamination
bad math
bad physics
bad choices
bad valve
Situations where pressure recovery becomes an issue
Things that favor laminar flow
small ascending aorta <3cm
Bentall
Mechanical AV
Indexed EOA for patient prosthesis mismatch
<0.85 cm2/m2
increased suspicion for valve obstruction
low lvot velocity
dvi <0.25
calculated eoa<predicted>100 ms</predicted>
VADS exam prebypass
AV function (stenosis, insufficiency)
Shunts (interatrial septal defects)
Intracardiac thrombus
Right ventricular function - RVEF , TR >mod?
Mitral valve function - (stenosis)
aortic atherosclerosis for outflow
STAR
Weaning VADS from bypass
evaluate lvad inflow cannula - avoid suckdown, vpeak <2 m/s
adequate flow - appropriate LV vol
AV function- no AI
shunts-interatrial septal defects
De-airing
RV function
VAD post bypass exam
RV function-usually the biggest problem
Unobstructed inflow cannula- vpeak <200m/s
volume status
intact septum
post op vads
hypoxia- look for pfo
cva- look for pfo or thrombus
HD instability - hypovolemia (bleeding) , tamponade, RV failure, infection, device failure