Prosthetic valves and VADs

Question 1

Echo assessment of prosthetic valves

Answer 1

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

Question 2

anatomic vs antianatomic mitral mechanical valve

Answer 2

anatomic- leaflets in same orientation as native valve
anti-antatomic- leaflets perpendicular (favors symmetric blood flow)

Question 3

Will protamine fix paravalvular leaks

Answer 3

small low velocity leaks typically resolve

Question 4

DVI for prosthetic aortic valve

Answer 4

normally .35-.5

Question 5

medtronic hall tilting disc regurgitant jet

Answer 5

large central, small peripheral

Question 6

st jude washing jets

Answer 6

directed inward

Question 7

on x washing jets

Answer 7

directed away (divergent)

Question 8

Differential for high gradient after replacement

Answer 8

bad measurement - over tracing, MR contamination
bad math
bad physics
bad choices
bad valve

Question 9

Situations where pressure recovery becomes an issue

Answer 9

Things that favor laminar flow
small ascending aorta <3cm
Bentall
Mechanical AV

Question 10

Indexed EOA for patient prosthesis mismatch

Answer 10

<0.85 cm2/m2

Question 11

increased suspicion for valve obstruction

Answer 11

low lvot velocity
dvi <0.25
calculated eoa<predicted>100 ms</predicted>

Question 12

VADS exam prebypass

Answer 12

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

Question 13

Weaning VADS from bypass

Answer 13

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

Question 14

VAD post bypass exam

Answer 14

RV function-usually the biggest problem
Unobstructed inflow cannula- vpeak <200m/s
volume status
intact septum

Question 15

post op vads

Answer 15

hypoxia- look for pfo
cva- look for pfo or thrombus
HD instability - hypovolemia (bleeding) , tamponade, RV failure, infection, device failure

Question 16

Indications for IABP

Answer 16

LV systolic failure
post bypass HD collapse
unstable angina
preop for high risk pts (LM disease, critical AS)

Question 17

contraindications to IABP

Answer 17

significant AI
significant aortic disease
aortic dissection
prosthetic graft in descending aorta
aorto-pulmonary shunt (BT shunt)

Question 18

complications of IABP

Answer 18

ao dissection, arterial perf
limb ischemia
thrombocytopenia
thromboembolic complications
balloon rupture w helium embolus
hematoma
psuedoaneurysm
infection
bleeding

Question 19

peak velocity cutoff for possible stenosis in prosthetic mitral valve

Answer 19

1.9-2.5 m/s

Question 20

mean gradient for possible stenosis in prosthetic mitral valve

Answer 20

6-10 mmHg

Question 21

DVI for possible prosthetic mitral stenosis

Answer 21

2.2-2.5

Question 22

EOA for possible prosthetic mitral stenosis

Answer 22

1-2

Question 23

PHT for possible prosthetic mitral stenosis

Answer 23

130-200 msec

Question 24

What LVAD power and speed likely indicates thrombosis with obstruction

Answer 24

power greater than 10 watts and pump speed remains around 900 rpm (power spike)

Question 25

lvad low flow alarm differential

Answer 25

suction event hypovolemia rv failure tamponade malignant hypertension inflow or outflow obstruction arrhythmia

Question 26

lvad high flow alarm differentail

Answer 26

sepsis or medication vasodilation rotor/bearing thrombosis with pump malfunction significant AI

Question 27

North south syndrome

Answer 27

occurs with VA ecmo as heart starts to eject and recover before the lungs recover. Ejects deoxygenated blood and ecmo ejects oxyenated blood

Question 28

Calculating PAPI and TPG

Answer 28

PAPI= PASP-PADP/ RAP TPG=MPAP-PCWP