1. health and fitness
2. disease

The Walking, Talking and Pulseless:
THE LVAD
Konstadina Darsaklis, MD
Heart Failure and Transplant Cardiologist
Center for Advanced Heart Failure and Transplant
Hartford Hospital
(860) 972-1212
Disclosures
WILL be discussing off label use of
various mechanical circulatory support
devices and medications
 We
What is ECMO?


Extracorporeal Membrane Oxygenation
The use of mechanical devices to temporarily
(days to months) support lung and/or heart
function (partially or totally) during
cardiopulmonary failure, leading to organ
recovery or replacement.
• ELSO – definition

Also known as:



ECLS (Life Support)
ECLA (Lung Assist)
ECCO2 (CO2 removal)
Basic ECMO Physiology
 Blood
is drained from patient to an
external pump
 Blood pumped through a membrane gas
exchanger


Oxygenation takes place
CO2 is removed
 Blood
is warmed and returned to
circulation
Where did ECMO come from?

Direct extension of principles of CPB

Smaller/transportable system closed to atmosphere
• New generation pumps

Centrifugal
• New generation oxygenators



Hollow-fiber membrane
Less Heparin
Specifically designed cannulae
• Shorter
• Coated (heparin, albumin)
• Dual lumen, multiport
ECMO Past

Heart/Lung Machine developed by
Dr. John Gibbon in 1939
 First successful heart operation
using heart-lung machine in 1954


All venous return diverted into
machine and pumped into
systemic circulation



ASD repair in an 18 year old
female
Heart is left empty
Heart surgery is facilitated
Caused damage to fluid and solid
elements of blood


Fatal if used for more than 2-3
hours
Major cause of blood damage was
direct exposure of blood to gas
• Plastic gas exchange membrane
solved most of these problems
NEJM 1972
Types of ECMO
 Veno-Veno

(V-V)
Vein to Vein
 Arterio-Veno

(A-V)
Artery to Vein
 Veno-Arterio

Vein to Artery
(V-A)
Veno-Veno (V-V) ECMO

One central vein to
another




Circuit inflow: VenaCava
Circuit outflow: Right
Atrium
Single double lumen
catheter (14 F) inserted
into IJ
Pulmonary support only


ARDS
H1N1
Pump
Oxygenator
V-V ECMO
CESAR TRIAL


UK based ARDS trial (Glenfield) of VV ECMO
180 patients with Murray score > 3 and pH < 7.2
randomized 1:1





Best care strategy
ECMO strategy
Primary outcome = death or disability at 6
months
Secondary outcome = death
Cost effectiveness evaluation
CESAR Trial

Results
16% survival benefit
without disability
Not for ECMO…
For
"Thetake-home
message
is that ECMO should be
referral to a specialized
center for
consideration
of
considered
for
most patients
who cannot receive
ECMO
lung-protective
ventilation and should be
 Cost per patient is 2x >
with ECMOas early as possible — before 7
implemented

days."
 Critique


Modest benefit if include
ECMO treated patients
No-benefit if exclude nonECMO treated patients
Arterio-Venous (A-V) ECMO



Pumpless, passive
flow
Depends on patient’s
CO
Cannulation:



FA  FV
Low flow rates
CO2 removal
Pump
Oxygenator
Veno-Arterial ECMO

De-Oxygenated blood
extracted from central
vein


Oxygenated blood
returned to Arterial
System


Fem, IJ, RA, etc.
Fem Art, Ax Art, Aorta
Respiratory AND
Hemodynamic
support
A
What does VA ECMO provide?
 Cardiac


Bi-Ventricular support
Up to 10 LPM
 Tissue


Oxygenation
Vent can be weaned
Oxygenator is REQUIRED
 CO2

Output
clearance
Oxygenator is REQUIRED
What it was… To what it is…
Recent advances in Technology
 Pump

Centrifugal pump (Rotaflow, CentriMag)
 Tubing


Shorter cannulation lines
Bi-Caval dual lumen catheters
 Oxygenation

Hollow-fiber membrane
Show me the data…
“Patients surviving 30 days had a
64% chance of being alive after 5
years.”
Smedira et al. J Thorac Cardiovasc Surg 2001; 122:92-102
Crit Care Med 2008 Vol. 36, No. 5
MCS and Cardiogenic Shock
Salvage/Emergency
Therapy
Maintenance
Therapy
Consider VA ECMO when…

Goal oriented device selection




Emergent (bedside) or Urgent need for MCSD
Oxygenation/Ventilation impairment
Unclear neurological status




Bridge to decision
Bridge to decision
Post Cardiac arrest and need hypothermia
Inability to come off Cardiopulmonary bypass
after operation
No availability of other modalities
Indications
 Acute
severe heart and/or lung failure with
high mortality risk despite optimal
conventional therapy


Consider when 50% mortality risk
Strongly consider when 80% mortality risk
 Severity
of illness and mortality risk is
estimated as precisely as possible using
measurements appropriate for age and
organ failure
ECMO does NOT treat the underlying condition!
It is ONLY a temporizing device!
Common Indications

Post-cardiotomy


Post-Heart Transplant


Inability to get patient off cardiopulmonary bypass
following cardiac surgery
Primary graft failure
Severe Cardiac Failure/Cardiogenic Shock




Decompensated cardiomyopathy
Myocaditis
Acute Coronary Syndrome
Drug overdose
Russo CF et al. JTCS, 2010; 140:1416-1421
Gariboldi V et al. Ann Thorac Surg 2010; 90: 1548-53.
Potential Complications of ECMO

Blood loss


Priming of tubing, pump and oxygenator
Bleeding
•
•
•
•

Thrombocytopenia



Platelet interactions with circuit
HIT II
Embolism



Catheter insertion
Anticoagulation
Thrombocytopenia
Vessel perforation during placement
Thrombus formation in circuit
Air
Catheter infection and sepsis
Potential Complications of ECMO



Pump malfunction
Tubing rupture
Cannula issues




Limb ischemia





Position
Displacement
Placement/removal
Particularly with fem-fem approach
Arterial bypass recommended
3-way stopcock rupture
Oxygenator malfunction
Heat exchanger malfunction


Water to blood leak
Hemolysis (increased free hemoglobin and decreased hematocrit)
Predictors of Morbidity and
Mortality

Predictors for In-Hospital Mortality






Age > 70 (OR 1.6)
Obesity (OR 1.8)
Persistent anaerobic metabolism after 24-48 hours of ECMO support
(OR 1.8)
Acute liver and renal failure (OR 2.1)
DM (OR 2.5)
Predictors for In-Hospital Mortality

Device insertion under cardiac massage (OR 20.68)
24 hour urine output < 500 ml (OR 6.52)
PT < 50% (OR 3.93)
Female sex (3.89)

Myocarditis associated with better outcome (OR 0.13)



Rastan AJ et al. J Thorac Cardiovasc Surg 2010; 139:302-311.
Combes et. al. Crit Care Med 2008 Vol. 36, No.5
Morbidity predictors
 Lack
of femoral artery bypass in fem-fem
approach

40% higher incidence of leg ischemia
 Underlying


coagulopathy
Predicted higher need for blood products and
re-thoracotomy
Mean PRBC transfusion rate 13 units/patient
Rastan AJ et al. J Thorac Cardiovasc Surg 2010; 139:302-311.
Contraindications

Absolute



Uncontrollable coagulopathy
No definite absolutes
Relative




Conditions incompatible with normal life if patient
recovers
Preexisting condition which affect the quality of life
(CNS status, end stage malignancy, bleeding risk)
Inability to anticoagulate
Futility
ECMO on the move
“ECMO on the Go”
VA ECMO vs. VAD
VA ECMO
VAD
Bi-V Support
+
++
Oxygenation/Ventilation Support
++
(+)
Insertion Time
Quick
More Time
Insertion Technique
Easy
More Complex
Maintainance
Easy
Easier
Duration
Short
Short/Long
Anticoagulation
More
Less
Complications
More
Less
Cost
Less
More
New Frontier
ECMO and PAH
What is PH?
Pulmonary hypertension is a progressive disorder that affects
both the pulmonary vasculature and the heart.
Leads to right heart failure and eventually death across all
PH groups
Significant mortality despite several treatment options
(mainly PAH group)
Oral therapy
IV therapy
Lung transplant
Updated Classification for Drug
and Toxin-induced PAH
Simonneau G et al. J Am Coll Cardiol. 2013; Vol 62, Suppl D: 62:D34‐41.
Hemodynamic Definitions
Pre-Capillary PH
Post-Capillary PH
Mixed PH
Hemodynamic Quiz - I
PASP > 35mmHg
mPAP > 25mmHg
mPCWP < 15mmHg
PVR > 3 WU
PAH
Hemodynamic Quiz – II
PASP > 35mmHg
mPAP > 25mmHg
mPCWP > 15mmHg
PVR < 3 WU
PVH
Hemodynamic Quiz - III
PASP > 35mmHg
mPAP > 25mmHg
mPCWP > 15mmHg
PVR > 3 WU
MIXED
Histopathology
Pathophysiology
Increase in pulmonary vascular
resistance (PVR)
↓
RV pressure overload
↓
RV hypertrophy to compensate for
increased wall stress (Adaptive
remodeling)
↓
Compensatory mechanism
insufficient
↓
Maladaptive remodeling
↓
Adaptations leading to RHF and
arrhythmias
- RV dilatation
- Tricuspid regurgitation
(?secondary)
- Atrial dilatation
- Interventricular septum
bowing during early diastole
Predictors of POOR Prognosis in IPAH
Eur Respir Rev December 1, 2011 vol. 20 no.
122 297-300
•
•
•
•
•
•
•
•
•
•
30F with IPAH referred to Hanover Medical School
WHO FC III
6MWD 402m
CPET VO2max: 11.6
TAPSE: 1.6cm (normal>2cm)
RHC: CO/CI 2.9/1.6, mPAP 62mmHg, PCWP 5mmHg, PVR: >19wu
Started on therapy: Sildenafil, bosentan
RHC CO/CI 4.2/2.3, mPAP 55mmHg, PCWP 5mmHg, PVR 11wu
2 years later: Syncope – crumped
RHC: CO/CI 3.4/1.9, mPAP 60mmHg, PCWP 4mmHg, PVR 16wu
Happy Ending…
• Within 48 hrs of admission, refractory RHF, renal
failure, lactic acidosis
• VA ECMO initiated, patient maintained conscious and
without ventilation for 42 days until suitable donor
organs became available
• On ECMO, renal function recovered fully, no infection,
bleeding or other complications
• Underwent successful bilateral lung transplantation
• Case illustrated the application of current ESC/ERS
guidelines “treat-to-target” recommendations in routine
clinical practice, and describes the successful use of
ECMO as bridge to lung transplantation following failure
of long-term medical management.
• Retrospective analysis
• 7 patients (3 female, mean age 31.7 ± 12.1 years
• Underwent lung transplant while on ECMO support May
2009-October 2011
• Not ventilated for more than 24 months before the LTx
• All patients were fully awake and kept on receiving
noninvasive ventilation for a variable amounts of time per
day after ECMO started
• ALL pts survived successfully until the transplant
• Survival after BLTx is comparable to that of patients who
were not on ECMO support
J Thorac Cardiovasc Surg
• Review of single center experience
• Endpoints:
• Successful bridging
• Duration of ECMO support
• Extubation
• Weaning from ECMO
• Overall survival
• ECMO-related complications
• During 5 year period (2007-2012)
• Acute respiratory failure in 18 patients, on institution’s lung
transplant waiting list
• Median age 34
• 8 hypoxemic
• 9 hypercarbic
• 1 combined
• 13 VV ECMO
• 5 VA ECMO
• 13 patients were successfully bridged: 10 to transplant, 3 to
recovery
• 11 patients (61%) survived beyond 3 months, including the 10
(56%) who underwent transplantation and are still alive
• 6 patients were extubated on ECMO – 4 of whom underwent
transplantation
• The median duration of ECMO for patients who underwent
transplantation was 6 days versus 13.5 days for those who did
not.
• Drainage from RIJV
• Reinfusion through a cannula grafted to the R subclavian artery
• Oxygenated blood travels retrograde through subclavian and innominate
arteries into the aortic arch
• Bypass patient’s native circulation
• ADVANTAGES:
• Avoid limb ischemia
• Mobilize easily
• Occasional brachial plexopathy can occur
Food for Thought…
• VA ECMO may be the optimal strategy in RV failure cases resulting
from PRESSURE overload caused by pulmonary obstruction
• RVAD will not allow increased blood flow through an obstructed
pulmonary bed AND may increase the risk of pressure-related lung
injury
• Left sided cardiac filling remains low
• Use of VA ECMO will decompress the RV, decrease the PA pressure
and increase left-sided pressure and facilitate preservation and
recovery of end-organ function
• May increase the LV afterload – result in LV overload
• REMEMBER: LV is chronically underloaded in patients with longterm PAH and acutely underloaded in PE
• The sudden overload with VA ECMO may cause LV failure
• Solutions?
• Surgical central cannulation (RA and ascending aorta
• Peripheral cannulation via right subclavian artery
• Increased risk of bleeding
TAKE HOME POINTS
• Given 12-24 month waiting period for lung transplantation
• Patients can acutely decompensate while waiting
• Need for prolonged intubation may render these patients
unsuitable for lung transplantation
• Can use ECMO when mechanical ventilation alone is not
enough to support their gas exchange needs
• ECMO may even allow some patients to be removed from
mechanical ventilation while awaiting transplant
• Let’s them eat
• Participate in their care
• Work with PT to ambulate
• especially upper body cannulation
• Potential to improve pre-transplant conditioning (rather than
allow it to worsen in this critical state)
Summary



ECMO Technology is substantially different than in the
recent past
ECMO is a feasible option for refractory cardiogenic
shock
Mobile options are being developed to ease transfer to
ECMO centers


I hope you like ambulance rides…
ECMO and PAH




Paucity of experience in the literature
No durable conclusions re: safety and efficacy
Small sample sizes of current data
MORE STUDIES!!!!
Thank you!
It ain’t what you don’t know that gets you in
trouble. It’s what you know for sure that just
ain’t so…
- Mark Twain