Download Left Ventricular Assist Devices

LVADs
LeftVentricularAssistDevices
MeganBoysen Osborn,MD,MHPE
AlisaWray,MD
Khuansiri Narajeenron,MD
CommonMechanicalCirculatorySupportDevices
Origin
Destination
Left VentricularAssist
Device(LVAD)
LeftVentricle
Aorta
RightVentricularAssist
Device(RVAD)
RightVentricle
Pulmonary Artery
ExtracorporealMembrane
Oxygenation(ECMO)
Veno-arterial(VA)
Common femoralveinà
IVC/RAjunction
Common femoralarteryà
Iliacartery
ECMO
Veno-venous (VV)
VVDualChamber
Rightcommon femoralvein
Rightinternaljugular vein
RIJ->SVC/IVC
Rightatrium
TandemHeart
Leftatria
Descending aorta
Intraaortic Balloon Pump
(IABP)
Aorta
Aorta
Impella
Left ventricularoutflow
tract
Aorta
Whydopeoplehave
anLVAD?
• Bridgetohearttransplantation(BTT)
• DestinationTherapy(DT)
• Bridgetorecovery(BTR)
FirstGeneration LVADs
1995
PulsatileFlow
Intraabdominal Insertion
“BridgetoTransplant”
18–24months*
2003:DestinationTherapy
SecondGeneration LVADs
2003
Continuous Flow
Intraabdominal Insertion
“BridgetoTransplant”or
“DestinationTherapy”
Somearealive>10years
ThirdGenerationLVADs
2012
Electromagnetic;
Pulsatile,Continuous
flow
Intrathoracic Insertion
“BridgetoTransplant”
ImagefromReliantHeart:http://reliantheart.com/new-heart-assist-5/smallest-size-and-weight/
ImageCourtesy: ByNationalHeartLungandBloodInstitute(NIH)(NationalHeartLungand BloodInstitute(NIH))[Publicdomain],viaWikimedia
Commons
Cost
MillerLW,Guglin M,RogersJ.CostofVentricularAssistDevices:CanWeAffordtheProgress?Circulation2012;127:743-748
Complications
Mostcommoncausesofdeath
• CardiacFailure
• Infection
• CNSEvent
Source:Kirklin JK,etal.JHeartLungTransplant.2010Jan;29(1):1–10
Complications
ReasonstheymightpresenttoyourED
• Dysrhythmia
• Infection/Sepsis(Driveline)
• CNSEvent(Ischemicorhemorrhagicstroke)
• Bleeding
• Pumpfailure/thrombosis
• Tamponade
• PulmonaryEmbolism
• AorticDissection
• LVADSuctionEvent
Management
• CalltheLVADCoordinator
• Checkwhetherdeviceisworking(skin
signs,hum/vibration,MAP)
• Checkconnections,plugintowall(need
powerpack)
• Checkalarms
• Echo
Management
• Fluids,?pressors?
• TrytoavoidCPR
• Candefibrillate/cardiovert (avoiddirectlyover
thedevice)
• ConsiderTPA/heparinvs.reversalofanticoagulation
• Checkpotassium
• TRANSFER
CommonAlarms
iRAT
individual Readiness Assessment Test
gRAT
group Readiness Assessment Test
GAE
group application exercise
Post test
kahoot!
Left Ventricular Assist Device (LVAD) Complications
Nick Stadlberger, MD
C Partyka et al. Emerg Med Australas, 2014. PMID 24707998
M Anderson et. al. J Heart Lung Transplant, 2009 PMID 19560703
JC Greenwood et al. Emerg Med Clin North Am, 2014. PMID 25441039
Tips
• These patients MAY NOT HAVE A PULSE
o May need ABG since pulse ox may
be inaccurate without pulse
• Contact your hospital’s or network’s LVAD
Coordinator immediately to help with
management and troubleshooting.
• Patients are usually on diuretics, and may
intravascularly depleted or have electrolyte
abnormalities
Image used with permission of Mayo Foundation for
Medical Education and Research
1
st
2
nd
rd
3
th
4
LVAD Patient in Extremis: Step-Wise Diagnostic Approach
Address airway, breathing, circulation; Obtain IV, O2, monitor
Measure blood pressure: May need manual cuff with Doppler to obtain
mean arterial pressure (MAP), or use arterial line (MAP goal 70-80 mmHg)
• Assign someone to call LVAD Coordinator
• Auscultate precordium. Is there a hum?
− Yes ! LVAD is working. No ! LVAD is not working.
• Battery – Make sure it is plugged in.
• Controller – Check for alarms.
• Driveline – Check device type, evidence of infection/damage
• Echocardiogram
• Obtain VAD variables: Flow, Power, Speed, Pulsatility Index
• Obtain ECG
• Obtain labs (CBC, electrolytes, coagulation studies, LDH, type and screen
given GI bleed risk, ± blood cultures for infection concern, ± ABG)
•
•
Echocardiogram
Findings
Big RV + Big LV
Big RV + Small LV
Small RV + Small
LV
Potential Causes
Pump failure,
Pump thrombosis
Valve disorders
Right heart failure,
ST-elevation MI
Pulmonary hypertension
Note: If LV to outflow cannula
size ratio is 1:1, then high risk
for suction event
Hypovolemia
Sepsis
GI bleed
Management
(with LVAD team)
Heparin, antiplatelet agents,
thrombolytics
IV fluids, ECG, consider
inotropes
IV fluids, consider blood
transfusion, antibiotics
Updated 11/21/16
LVAD
Complication
Arrhythmia
Infection
Thrombus
(pump thrombus,
PE, stroke/TIA)
Bleeding
Suction Event
(An underfilled LV
causing suction of
myocardium into
LVAD)
RV Failure
Cannula
Malposition
Device
Malfunction,
Pump Failure
Comment
Up to 50% with sustained
VT/VF in first 4 weeks after
LVAD placement
Difficult to determine primary
vs. secondary cause:
• Primary: compromised
myocardium + scar tissue
Secondary: electrolyte
abnormalities, hypotension,
suction events
Up to 42% experience sepsis
within 1 year (REMATCH
Study). Most infections are in
first 3 months. 9% are fungal.
High risk despite anticoagulation.
Pump thrombus suggested by
warm device and increased
power output. Elevated LDH
Patients may have an acquired
Von Willebrand Disease
coagulopathy
Can be caused by right heart
failure, hypovolemia, sepsis,
restrictive cardiomyopathy,
arrhythmias
Due to AMI or previous RV
failure
Consider in setting of new VT,
suction event, chest
compressions, or trauma
Suggested if no hum and MAP
<40 mmHg
Management
(with LVAD team)
Depending on the cause:
• IV fluid challenge is
reasonable
• Reduce pump speed
• Correct electrolytes
• Electrical or
pharmacologic
(amiodarone)
cardioversion
Broad spectrum antibiotics
+ antifungal
Heparin, thrombolytics,
antiplatelet agents
If life-threatening, reverse
anticoagulation and
transfuse as needed.
IV fluids to increase LV
filling
IV fluids and consider
inotropes. Aspirin and
heparin if AMI
Requires surgical
exploration
Treat cardiogenic shock: IV
fluids, vasopressors, ACLS
protocols, consider heparin
for thrombosis
Cardiac Arrest
Multiple potential causes
ACLS algorithms except:
including all those listed above
• Chest compressions are
controversial as they could
dislodge the device.
• Do NOT place defibrillation
pads directly over device.
• Assign one person to
assess device placement
during and after code.
AMI: acute myocardial infarction; GI: gastrointestinal; LV: left ventricle; MAP: mean
arterial pressure; PE: pulmonary embolism; ROSC: return of spontaneous circulation;
RV: right ventricle; TIA: transient ischemic attack; VT: ventricular tachycardia; VF:
ventricular fibrillation
Updated 11/21/16
Updated 11/21/16
Left Ventricular Assist Device
Team Based Learning
individual Readiness Assessment Test (iRAT)
1. Which of the following is an INCORRECT method of assessing circulation in an
LVAD patient?
a. Using an arterial line to obtain mean arterial blood pressure (MAP)
b. Auscultate and palpate the precordium, listening and feeling for a hum or vibration
c. Checking a patient’s radial pulse
d. Checking tissue perfusion (capillary refill, mental status, urine output, skin signs)
e. Using a manual blood pressure cuff with doppler to measure mean arterial blood
pressure (MAP)
f. Using a manual blood pressure cuff with doppler to measure systolic and diastolic
blood pressure (SBP and DBP)
g. A&E
h. C&F
2. What is an acceptable MAP in a patient with an LVAD?
a. <60 mmHg
b. 60-80 mmHg
c. 80-110mm Hg
d. >110 mmHg
3. Which of the following is an indication for cardiopulmonary resuscitation (CPR)
in a patient with an LVAD?
a. Absent pulses
b. Loss of consciousness
c. MAP < 60 mm Hg
d. MAP = 0 mm Hg and pump stopped
e. None of the above
4. A 65 yo LVAD patient presents with upper GI bleeding. Why is bleeding common
in LVAD patients?
a.
b.
c.
d.
e.
Oral anticoagulant and anti-platelet use
Acquired Von-Willebrand’s Disease
Increased risk of AVM due to chronic low pulse pressure.
Platelet dysfunction
All of the above
5. You are monitoring an LVAD patient, who starts to become altered. Mean
arterial pressure is measured as 50 mmHg. The patient’s capillary refill is 4 seconds.
The controller alarm is flashing “low flow.” The cardiac monitor is shown below.
What is your next step management?
a. Check for battery power and line connection and contact the patient’s LVAD
company.
b. Check electrolytes (potassium, magnesium) and start amiodarone
c. Synchronize cardioversion at 100 Joules
d. Perform a 12 lead EKG and consult EP cardiologist to do a catheter ablation
e. Defibrillation at 200 Joules
6.Your LVAD patient develops hypotension and the controller alarm flashes “low
flow.”
Match the following echo finding with their associated disease entities: Put each number
in the appropriate box in the table below (more than one number can be in each box).
1. Pump not working or pump thrombosis
2. Significant AR (aortic regurgitation)
3. Hypovolemia/Bleeding
4. Massive PE
5. Right ventricular failure (MI)
6. Cardiac tamponade
7. Left Ventricular (LV) suction event
RV size: Decrease
LV size: Decrease
LV size: No Change
LV size: Increase
RV size: No change
RV size: Increase
Left Ventricular Assist Device
Team Based Learning
group Readiness Assessment Test (gRAT)
1. Which of the following is an INCORRECT method of assessing circulation in
an LVAD patient?
a.
b.
c.
d.
e.
f.
g.
Using an arterial line to obtain mean arterial blood pressure (MAP)
Auscultate and palpate the precordium, listening and feeling for a hum or
vibration
Checking a patient’s radial pulse
Checking tissue perfusion (capillary refill, mental status, urine output, skin signs)
Using a manual blood pressure cuff with doppler to measure mean arterial blood
pressure (MAP)
Using a manual blood pressure cuff with doppler to measure systolic and diastolic
blood pressure (SBP and DBP)
A&E
C&F
2. What is an acceptable MAP in a patient with an LVAD?
a.
c.
d.
<60 mmHg
60-80 mmHg
80-110mm Hg
>110 mmHg
3. Which of the following is an indication for cardiopulmonary resuscitation
(CPR) in a patient with an LVAD?
a.
b.
c.
e.
Absent pulses
Loss of consciousness
MAP < 60 mm Hg
MAP = 0 mm Hg and pump stopped
None of the above
4. A 65 yo LVAD patient presents with upper GI bleeding. Why is bleeding
common in LVAD patients?
a.
b.
c.
d.
Oral anticoagulant and anti-platelet use
Acquired Von-Willebrand’s Disease
Increased risk of AVM due to chronic low pulse pressure
Platelet dysfunction
All of the above
5. You are monitoring an LVAD patient, who starts to become altered. Mean
arterial pressure is measured as 50 mmHg. The patient’s capillary refill is 4
seconds. The controller alarm is flashing “low flow.” The cardiac monitor is
shown below. What is your next step management?
a.
b.
d.
e.
Check for battery power and line connection and contact the patient’s LVAD c
company.
Check electrolytes (potassium, magnesium) and start amiodarone
Synchronize cardioversion at 100 Joules
Perform a 12 lead EKG and consult EP cardiologist to do a catheter ablation
Defibrillation at 200 Joules
6. Your LVAD patient develops hypotension and the controller alarm flashes
“low flow.”
(Matching) Put each number in the appropriate box in the table below (more than
one number can be in each box). Match the following echo finding with their
associated disease entities:
1.
2.
3.
4.
5.
6.
7.
Pump not working or pump thrombosis
Significant AR (aortic regurgitation)
Hypovolemia/Bleeding
Massive PE
Right ventricular failure (MI)
Cardiac tamponade
Left Ventricular (LV) suction event
LV size: Decrease
RV size: Decrease
RV size: No change
RV size: Increase
3,6,7
3,7
4,5
LV size: No Change
LV size: Increase
4,5
1,2
RAT Key: Please insert and attach your RAT Key, please use page breaks to keep gRAT
on its own page.
1. Which of the following is an INCORRECT method of assessing circulation in an
LVAD patient?
Answer: H: Continuous flow LVAD (CF-LVAD) devices are the most widely used LVAD
devices.4 Patients, therefore, may have diminished or absent pulses. Similarly, because
flow is not pulsatile, measuring systolic and diastolic blood pressures is not applicable.
2. What is an acceptable MAP in a patient with an LVAD?
Answer B. 60-80 mmHg
According to Feldman,5 patients with a CF-LVAD should have a mean blood pressure
less than 80 mm Hg and [greater than 60].
3. Which of the following is an indication for cardiopulmonary resuscitation (CPR) in a
patient with an LVAD?
Answer D. MAP = 0 mm Hg and pump stopped is an indication for CPR. Fluid bolus and
device optimization should be attempted in patients with a low MAP. Absent pulses are
common in patients with continuous flow LVADs. Patients who are unconscious do not
necessarily need CPR. Cardiopulmonary resuscitation puts patients at risk for device
dislodgment.
4. A 65 yo LVAD patient presents with upper GI bleeding. Why is bleeding common in
LVAD patients?
Answer E. All of the above: Patients with LVADs take oral anticoagulants and antiplatelet agents. They have acquired Von-Willebrand’s disease from the shear stress of
CF-LVADs may cause proteolysis on von Willebrand’s factor.6,7 Patients are also at risk
of arteriovenous malformations due to chronic low pulse pressure.
5. You are monitoring an LVAD patient, who starts to become altered. Mean arterial
pressure is measured as 50 mmHg. The patient’s capillary refill is 4 seconds. The
controller alarm is flashing “low flow.” The cardiac monitor is shown below. What is
your next step management?
Answer: C: Synchronize cardioversion at 100 Joules. The patient is unstable and
therefore not a candidate for IV anti-arrhythmics alone. The patient has a MAP of
50mmHg, so therefore can be cardioverted, rather than defibrillated.
6.Your LVAD patient develops hypotension and the controller alarm flashes “low flow.”
(Matching) Put each number in the appropriate box in the table below (more than one
number can be in each box). Match the following echo finding with their associated
disease entities:
RV size: Decrease
LV size: Decrease
3,6,7
RV size: No change
3,7
LV size: No Change
LV size: Increase
RV size: Increase
4,5
4,5
1,2
Left Ventricular Assist Device
Team Based Learning
Group Application Exercise (GAE)
A 50 yr old female with history of DM and ischemic cardiomyopathy status post
LVAD (Heartmate II) for bridge to heart transplant two week ago presents after
collapsing at her routine follow up appointment, 5 minutes prior to arrival.
1. What is your differential diagnosis?
2. How will you assess her perfusion after you manage her airway and breathing?
3. From your answer to #2, you decide that the LVAD is not working. What are
your next steps?
4. You fix the issue in #3, and feel the LVAD is working, but the alarm is going off
and the MAP is <60. What are your next steps?
5. The machine is hot and the Echo shows normal RV size but dilate LV. What is the
possible cause?
6. How to investigate and manage the diagnosis in #5?
7. What is the definitive therapy for pump failure?
8. What is the definitive therapy for significant Aortic Regurgitation?
Left Ventricular Assist Device
Team Based Learning
Group Application Exercise (GAE): Key
Case:
A 50 yr old female with history of DM and ischemic cardiomyopathy status post
LVAD (Heartmate II) for bridge to heart transplant two week ago presents after
collapsing at her routine follow up appointment, 5 minutes prior to arrival.
1. What is your differential diagnosis?
Acute stroke, intracranial hemorrhage, cardiac arrest, pump failure or thrombosis, cardiac
tamponade, massive PE, dysrhythmia, hypoglycemia, severe active bleeding,
pneumothorax, aortic dissection, sepsis, acidosis
2. How will you assess her perfusion after you manage her airway and breathing?
-Listen for hum over precordium
-Feel vibration over precordium
-Doppler MAP
-Skin signs
-Assess mental status
3. From your answer to #2, you decide that the LVAD is not working. What are
your next steps?
-Contact LVAD team coordinator
-Check batteries
-Plug in LVAD in
-Check connections
-Make sure drive line is connected
-Check alarms, what are alarms saying?
4. You fix the issue in #3, and feel the LVAD is working, but the alarm is going off
and the MAP is <60. What are your next steps?
-Echo, EKG, cardiac monitor, fluid bolus, IV access, labs, ABG
-Check which alarms are going off (Is there low flow? Is the machine hot?)
5. The machine is hot and the echo shows a normal RV size but dilated LV. What is
the possible cause?
-Pump thrombosis, see table 4b in Stainback, et al6
-Pump malfunction of mechanical component
-Significant Aortic regurgitation
6. How to investigate and manage the diagnosis in #5?
- Consult cardiologist or contact LVAD team coordinator
- Compare echo with previous echo
- Clinical features associated with pump thrombosis include: intravascular hemolysis
(Hemoglobinuria, elevated creatinine, total billirubin and elevated LDH), high power
alarm, Hot device
- Check prothrombin time (PT)/Partial thromboplastin time (PTT)/International
normalized ratio (INR), complete blood count, lactate dehydrogenase, liver function tests,
creatinine, urinalysis
-Goal INR depends on the device and ranges from 2.0 to 3.5.
7. What is the definitive therapy for pump failure?
-Tissue plasminogen activator (TPA)
-Heparin
8. What is the definitive therapy for significant Aortic Regurgitation?
-Bioprosthetic valve
-Heart transplant