Care of the Left Ventricular Assist Patient

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LVAD BASICS
HEART MATE II
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Continuous flow axial pump
FDA approved for BTT , DT, BTD
Valve less system
Generates 10 liters of output (4-7L)
Runs in fixed mode RPM 8-13 (8-10)
Continuous unloading of LV
throughout cardiac cycle this
eliminates arterial pulse Use of
doppler for b/p measurement MAP
70-90
BENEFITS OVER PULSATILE PUMPS
 Lighter and smaller than pulsatile
pumps
 May be used in smaller patients
 Quiet
 Increased durability
 Better suited for long term support
 Improve hemodynamics, end organ
function quality of life and functional
capacity
SURGICAL PROCEEDURE
 Median Sternotomy
 Inflow cannula apex of LV
 Outflow cannula anastomosed to ascending
aorta
 Pump placed in pre peritoneal position,
intra abdominal placement can also be used
 Driveline positioned in a gentle loop with
punch or slit through muscle and stabilized
with a suture
CRITICAL ELEMENTS FOR
SUCCESSFUL LVAD
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Patient Selection
Pre op preparation
Timing of implant
In a word RESPECT the RV
PATIENT SELECTION
Appropriateness for VAD support based on
degree of illness
Ability to successfully undergo surgery
Family support
Implant prior to end organ damage
Class IIIB IV
Maximal medical therapy
Peak VO2< 14ml/kg/min.
Heart failure survival score/Seattle Heart
Failure Model estimates HF survival 1-2
years
PRE OPERATIVE PREPARATION
 OPTIMIZE RV as RV failure leading cause of
morbidity and mortality with LVAD
 Echo to assess RV size, function and
tricuspid regurg.
 RHC initially and prior to implant for
diuresis and unloading with inotropes IABP
 RVSWI may be a predictor of RV function
 Ie CVP<15, PVR<4 wood units,
transpulmonary gradient < 15mmHg,
RVEDV 200cc RVESV <177
TIMING OF IMPLANT
 Prior to end organ damage renal liver
malnutrition
 Opt to delay until co morbidities can
be reversed or controlled
 Prior to RV dilatation/decreased
function
 Trend towards earlier implant and
referral
CASE STUDY
 Mr. MO is a 46 year old African American
male with a history of MI at the age of 26
with normal EF, PVD s/p fem pop bypass
2005 diabetes 2007 and HLD. Treated
appropriately and. was compliant
 Admitted to hosp Jan 09 for
decompensated HF Echo showed an EF of
20% normal RV size and function Diuresed
and placed on appropriate medications.
MEDICATIONS
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Coreg 6.25 bid
Hydralazine 25 tid
Imdur 30 qd
Januvia 100 qd
Digoxin .125
Lasix 40 qd
Aldactone 25
Lipitor 80 qd
FURTHER TREATMENTS
 ICD implanted for Primary prevention
2/9 echo with EF 15%
 5/10 Upgraded to BIVICD 6/24
 Much improved post BIV implant
Walking 3 miles a day
 Further Medication titration Coreg 25
 Echo repeated 9/13 improvement in
EF to 20-25% RV normal new wall
motion abnormality
 Angiogram mid LAD occlusion distal
filling mod pulmonary HTN Admitted
post angiogram for diuresis
secondary to elevated pressures RA
23 PCWP 31 BNP 2550 diuresed and
felt better
 9/10 Seen in office stable but
decreased activity tolerance CPX
ordered Prelim VAD transplant
discussion initiated
CPX 8.6 unable to complete test
Zaroxolyn added twice a week
Family meeting with VAD coordinator
W/U initiated
11/18 RHC RA 26 PCWP 23 CI 1.9
Echo mod TR EF 25 normal RV
 12/10 Lengthy discussion re
VAD/Transplant he feels he is too
healthy and wants to think about
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 1/11 Admitted for decompensated HF abd distension
wt gain able to walk 100 feet BNP 2550 ECHO EF 20%
RV mildly dilated
 2/11VAD discussion intensify still feels he is too
healthy despite medical evidence to contrary.
 3/16 Admitted for decompensated HF PICC line placed
for home dobutamine continues to refuse VAD
 4/9 Admitted with fever chills Creat 4 MRSA from
PICC Paracentesis for 3 L Agrees to go for VAD eval
 5/17 Denied VAD/Transplant due to severe RV failure
DISCUSSION
 Paucity of effective therapies for advanced
heart failure which led to evolution of
assist devices.
 REMATCH TRIAL pivotal trial
 Increase in number of LVADS implanted
past 3 years in large part due to HMII
 6 Pulsatile and 9 continuous flows in trials
not approved YET.
 Learning curve as with anything More you
implant the better you do.
STATISTICS
 Survival Rematch trial one year 23% with
pulsatile
 Transition from pulsatile to continuous
dramatic beginning in 2008 98% of adult
LAVD implanted
 One year survival 74% 2 year 66%(cont)
67% one year 46% 2 year pulsatile
 Increase in DT and decrease in implants for
C shock 35 to 17%
 DT accounts for 15% of all implants
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