1. Centrifugal or Axial LVAD? : Denis Papin versus Archimedes
H. Edward Garrett, Jr., MD
February 27, 2016

2. Implantable Ventricular
Intracorporeal
Implantable Ventricular
Assist Devices
Pulsatile
Continuous Flow
Axial Flow
Centrifugal Flow

3. Disclosures HeartMate II Principal Investigator (Study Completed)
XVE Registry Principal Investigator (Study Completed)

4. HeartMate® XVE LVAS Pneumatic driven piston pump
First approved device for bridge to transplant and destination therapy
Pulsatility is advantageous
Disadvantages in size and durability
First generation pulsatile left ventricular assist device HeartMate XVE... - Scientific Figure on ResearchGate. Available from: [accessed Feb 15, 2016]

5. HeartMate II® Axial flow pump
Approved for bridge to transplant and destination therapy
HeartMate II left ventricular assist device and cross-sectional... - Scientific Figure on ResearchGate. Available from: [accessed Feb 15, 2016]

6. Axial Flow Pump
Differ from radial flow in that the fluid enters and exits along the same direction parallel to the rotating shaft.
The fluid is not accelerated but instead “lifted” by the action of the impeller.
The pump may be likened to a propeller spinning in a length of tube.

7. HeartWare hVAD® System
Centrifugal flow pump
Approved for bridge to transplant
Current study in progress for destination therapy
External (a) and internal (b) view of third-generation continuous-flow... - Scientific Figure on ResearchGate. Available from: [accessed Feb 15, 2016]

8. Centrifugal Pump
A rotodynamic pump that uses a rotating impeller to increase the pressure and flow rate of fluid.
Most common pump used to move liquids through a piping system.
Fluid enters the pump impeller along or near the rotating axis and is accelerated by the impeller, flowing radially outward or axially into a diffuser or volute chamber, then exits into the downstream piping system.

9. Axial flow pump attributed to Archimedes although he may have improved upon a design used to irrigate the Hanging Gardens of Babylon =

10. Archimedes Born 287 B.C. in Syracuse, Sicily
Killed by a Roman soldier 212 B.C. After 2 years siege at Syracuse in the Second Punic War

11. Contributions
Archimedes principle for determining the volume of an object with irregular shape
Value of π
Defensive war machines like Claw and Archimedes Ray

12. Archimedes screw (water pump) used in largest ship built in antiquity

13. Denis Papin Born in Blois, France 1647 Died a pauper in London 1712

14. Contributions Centrifugal pump Pressure cooker
Steam driven paddle wheel boat

15. Heart Mate II® Heartware hVAD®
Mechanism
Continuous Flow, Axial
Continuous Flow, Centrifugal
Operating Range
(Typical range)
6, ,000 rpm
(8, ,000 rpm)
2, ,200 rpm
(2, ,800 rpm)
Inflow Sintering
Complete
Partial (ring)
Placement
Subdiaphragmatic
Intrapericardial
Anti-Thrombotic Rx
Asa/Coumadin
BTT Approval?
Yes, 2008
Yes, 2012
DT Approval
Yes, 2010 No
Implants Worldwide
>21,000
>9,000
Goldstein DJ, Continuous Flow Left Ventricular Assist Devices: Dare to Compare, The Journal of Thoracic and Cardiovascular Surgery (2015), doi: /j.jtcvs

16. Comparison of Axial vs Centrifugal Pumps
Moazami N, Fukamachi K, Kobayashi M, et al: Axial and centrifugal continuous-flow rotary pumps: A translation from pump mechanics to clinical practice. J Heart Lung Transplant 32:1-11,2013

17. LOS
2 years
Activated coagulation and immune system
Pump Thrombosis
Heartmate II®
20 days
12%
Higher
Heartware®
16 days
28%
Lower

18. Both Heartmate II® and Heartware hVAD ® pumps have been proven fairly equally successful with similar one year survival rates 85 – 90%
Both achieve similar flow rates up to 10 L/M
Similar rates of GI Bleeding occurrences

19. Moazami N, Fukamachi K, Kobayashi M, et al: Axial and centrifugal continuous-flow rotary pumps: A translation from pump mechanics to clinical practice. J Heart Lung Transplant 32:1-11,2013

20. Heartmate 3™ Now in clinical trials MOMENTUM 3 IDE
Centrifugal pump with many similarities to Heartware hVAD®
Bourque K, Gernes, D, Loree H, et al: HeartMate III: Pump Design for a Centrifugal LVAD with a Magnetically Levitated Rotor ASAIO J , 2001

21. Questions?