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Title: ?An Equal Opportunity University


1
Evolution of Mechanical Circulatory Support
From the Balloon Pump to the Destination
Ventricular Assist Device
Charles Hoopes MD Jason Alexander Gill Professor
in Thoracic Surgery Section Chief, Heart and Lung
Transplant/Mechanical Circulatory
Support Director, UK Comprehensive Transplant
Center University of Kentucky Lexington, KY
?An Equal Opportunity University
2
Evolution of Mechanical Circulatory Support
From the Balloon Pump to the Destination
Ventricular Assist Device
Objectives Discuss the history of mechanical
circulatory support devices from the balloon pump
to the first artificial hearts and destination
VADs. Describe the evolution of the mechanical
assist device from early conception to todays
current technology in successful treatment of
advanced heart therapy. Describe the clinical
implications for implantation of devices and
recovery and what issues future devices may
solve.  
I have no financial disclosures I have no
financial relationship with any of the
technologies discussed I will not discuss any off
label use of current technologies
Charles Hoopes MD Jason Gill Professor in
Thoracic Surgery Section Chief, Cardiopulmonary
Transplant/Mechanical Circulatory Support
Director, UK Transplant Center University of
Kentucky
?An Equal Opportunity University
3
Conceptual eras of mechanical circulatory
support..
1812 Le Gallois parts of the body may be
preserved by external perfusion
Etienne-Jules Marey (Paris,1881) physician,
inventor
.. the 1st artificial heart
Guillotined head of a dog in perfusion
experiments of Brukhonenko and Tchetchuline. This
preparation relied on gas exchange from a second
donor dog's lungs. Diaphragm-like pumps pumped
blood into the recipient dog's carotid arteries.
Dog heads perfused in this manner remained
functional for a few hours. (Reprinted from
Brukhonenko S, Tchetchuline S. Experiences avec
la tete isolee du chien.1.Technique et conditions
des experiences. J Physiol Pathol Gen 19292742)
..a biological oxygenator
4
Intellectual origins of mechanical assist and
circulatory support
Experimentally, it is possible to completely
replace the heart with an artificial heart, and
animals have been known to survive as long as 36
hours. This idea, I am sure, could be reached to
full fruition if we had more funds to support
more work, particularly in the bioengineering
area DeBakey (1963) Senator Lister Hills
Subcommittee on Health
In Jan of 1964 James Hardy consented the sister
of Boyd Rush a 68 yo comatose deaf mute with
ischemic heart failure and lower extremity
gangrene for the insertion of a suitable heart
transplant if such should be available. Rush
decompensated and was placed on cardiopulmonary
bypass. In the absence of a viable donor Hardy
transplanted the heart of a 45 kg chimpanzee. The
heart provided hemodynamic support for 90 minutes
May 1965
..surgeons at Baylor hailed the Jackson
transplant. The Baylor surgeons say there are two
solutions for support of the failing
heart..transplants from humans or animals and
artificial hearts. The Baylor group is
concentrating its efforts on developing an
artificial heart. Associated Press, 25 Jan 1964
5
Physiologic basis ..mechanical pumping of
blood to viscera previously inadequately perfused
reducing the workload and oxygen consumption
of the myocardium
Ann Review Med 1966
6
Evolution of Mechanical Circulatory Support
1981
1982
1965
1969
1936
1968
As socio-political history
7
Evolution of Mechanical Circulatory Support
HeartWare
Thoratec
Abiomed
As medical technology
8
Evolution of Mechanical Circulatory Support
  • Historical context
  • oxygenators and pumps, biological and
    mechanical
  • Application (why are you doing this and what do
    you want)
  • moratorium of decision (non-durable )
  • bridge to recovery (non-durable and durable)
  • bridge to transplant (non-durable and durable)
  • destination therapy (durable)
  • Deployment (how do we do it and when do we try)
  • Problems (general, device specific, and evolving)

As clinical medicine
9
  • Historical truisms in mechanical circulatory
    support (MCS)
  • Deployment of MCS technologies in the context of
    medical futility
  • results in futile deployment of technology MCS
    is capable of resuscitation, not
  • reanimation
  • MCS technology restores hemodynamics (gt86) but
    may not
  • alter survival depending upon the specifics of
    deployment
  • Unnecessary surgery performed well has
    excellent outcomes
  • device technology should be deployed based upon
    clinical trajectory and
  • the natural history of the disease process
  • Physiology always trumps engineering..
  • MCS can support patients awaiting good clinical
    decision making but
  • is ineffective in supporting bad clinical
    decisions

10
3 October 1930 ..at 8AM respirations ceased and
the blood pressure could not be obtained. Within
6 min and 30 sec Dr. Churchill opened the chest,
incised the pulmonary artery, extracted a large
pulmonary embolus, and closed the incised
wound.. the idea occurred to me if it were
possible to remove continuously some of the blue
blood from the patients swollen veins, put
oxygen into the blood and allow carbon dioxide
to escape from it, and then to inject
continuously the now red blood back into the
patients arteries, we might have saved her life.
We would have bypassed the obstructing embolus
and performed part of the work of the patients
heart and lungs outside the body.
JH Gibbon
Gibbon JH Jr (1939) The maintenance of life
during experimental occlusion of the pulmonary
artery followed by survival. Surg Gynecol Obstet
69604
11
The original TandemHeart
Dennis et al (1962) Ann Surg 156623
12
The Percutaneous Ventricular Assist Device in
Severe Refractory Cardiogenic Shock
Cardiogenic shock SBPlt90mmHg, CIlt2
L/min, inadequate end organ perfusion with
IABP/pressor support 88 ischemic, 37
non-ischemic (9 myocarditis) pLVAD
(TandemHeart) SVO2gt70, MAPgt60mmHg, AoV DOS 5.8
daysMSOF(n31),CVA(n8)
  • Pre pLVAD Post pLVAD
  • Cardiac index, l/(minm2) 0.52 (0.8) 3.0 (0.9)
  • SBP, mm Hg 75 (15) 100 (15)
  • DBP, mm Hg 30 (20) 65 (20)
  • MAP, mm Hg 45 (20) 81 (15)
  • HR, beats/min 105. 118.0
  • SVO2, 49 (11.5) 69.29 (10)
  • PCWP, mm Hg 31.52 17.29
  • PAP mm Hg 39.16 26.70
  • Lactic acid, mg/dl 24.5 (74.25) 11.0 (12)
  • LDH, U/dl 602 (630) 416.5 (335)
  • pH 7.22 0.14 7.44 0.06
  • Urine output, ml/day 70.3 1200
  • Hemoglobin 11 10.25

Kar et al (2011) JACC 57688
13
Pumping improved two patients' circulatory
status one survived. Two patients died before
pumping could begin in another, an abdominal
aortic aneurysm prevented insertion of the pump
Kantrowitz et al (1968) JAMA 203135
14
RETROSPECTIVE ANALYSIS OF 286 PATIENTS REQUIRING
CIRCULATORY SUPPORT WITH THE INTRAAORTIC BALLOON
PUMP
From 1972 through 1974, we implanted the pump in
34 patients. Of those patients, only 2 (1 in 1973
and 1 in 1974) survived until explantation, and
only 1 (the patient in 1974) survived to
discharge. Yet the intraaortic balloon pump
remains essentially unchanged today, and survival
rates of 70 to 80 can be expected when the
device is implanted in appropriately selected
patients This experience emphasizes the danger
of premature randomized studies, which can expose
technology to errors that are manmade rather than
inherent. OH Frazier (2005) Tex Heart Inst J
3260
Johnson et al (1977) Cardiovasc Dis 4(4)428436.
Device function must match patient
need preservation of end organ perfusion
(survival) and capacity for functional myocardial
recovery The timing of implantation is critical
to patient survival Mechanical circulatory
support (MCS) as a clinical program, not an
isolated procedure
15
Escalation therapy criteria and MCS
applicationand deployment
Hemodynamic instability CIlt1.8, CPOlt0.53,
PCWPgt18 FiO2/PaO2lt300, high inotropy
CPO MAP x CO/451
0.53
Cardiac power is the strongest
hemodynamic correlate of mortality in cardiogenic
shock A report from the SHOCK trial registry
Fincke (2004) JACC 44340
16
Ben Roe and the UCSF artificial heart circa 1970
post LVAD
17
Left ventricular assist vs. biventricular
replacement Durable vs non-durable applications
Heartware (impellar)
Syncardia TAH
AbioCor TAH
Heartmate II (axial flow)
18
Evolution of implantable mechanical cardiac
assist technologies
II
III
I
19
The complexity of mechanical circulatory support
technologies represents epidemiologya
significant clinical needcardiogenic shock is
highly morbid and frequently lethal
(gt55) absence of a common effective therapy
anecdotal experience not supported by clinical
trials pkVO2 12-16 ml/kg/min variability of
clinical application
Ongoing RCT in low risk pts with pkVO2 12-16
ml/kg/min
Crash and burn will get bridge to durable device
1. Critical cardiogenic shock 2. Progressive
decline 3. Stable inotrope dependent 4.
Recurrent advanced disease 5. Exercise
intolerant 6. Exercise limited 7. Advanced NYHA
class III
Inotrope dependent
20
Risk factors for death in patients with an
implantable mechanical circulatory support
device older patient age at the time of
implant (relative risk RR 1.41, p lt
0.001) assignment to INTERMACS Level 1
category characterized by cardiogenic shock
with life-threatening hypoperfusion (RR 1.59,
p 0.02) indicators of severe right
ventricular failure, such as ascites and
hyperbilirubinemia, which are clinically evident
at the time of implant
Pagani et al (2009) J Heart Lung Transpl
21
INTERMACS
Competing Outcomes Level 1 Critical
Cardiogenic Shock (n186)
Competing Outcomes Level 2 Progressive
Decline (n148)
Proportion of patients
Transplanted 40
Transplanted
Proportion of patients
Dead 29
Alive
Alive 26
Dead
Recovery 5
Months after Device Implant
Months after Device Implant
Competing Outcomes Level 3 Stable but
Inotrope Dependent (n35)
Alive
Proportion of patients
Transplanted
Dead
Months after Device Implant
22
Evolution of mechanical circulatory
supportventricular assist devices
Moratorium of decision Bridge to recovery Bridge
to transplant Destination (CMS)
Are VADs an operationor part of an integrated
heart failure program?
Slaughter M (2010) Will destination therapy be
limited to large transplant centers? Texas Heart
Inst J 37(5)562
23
The evolution of mechanical cardiopulmonary
support the learning curve
No device has ever saved or killed a patient
good physicians using good devices have done both
No device program has everything effective
device programs have everything they need
Device technology accomplishes nothing but
facilitates everything
24
LVAD induced remodeling Basic science and
clinical implications for recovery
biomarkers of recovery (genetic,structural,meta
bolic) therapeutic intervention (pre,post,and
peri) etiology of CHF (sequential tissue)
May 08
Inotrope dependent
BNP
Leftward shift of the EDPVR (structural reverse
remodeling) Time dependent reduction in heart
size (EDP of 30 mmHg, V30) Regression of
cellular hypertrophy
Dec 08
Dec 08
LVAD
Pre-explant(12)
inotropes
LVAD pod1
Explant pod7(103)
Explant pod1
Feb 09
s/p LVAD
25
LVAD induced remodeling Basic science and
clinical implications for recovery
May 08
Inotrope dependent
Leftward shift of the EDPVR (structural reverse
remodeling) Time dependent reduction in heart
size (EDP of 30 mmHg, V30) Regression of
cellular hypertrophy
Dec 08
Dec 08
LVAD
Feb 09
s/p LVAD
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