1. Self-expanding, anatomically correct transapical aortic valve implantation
Ehud Schwammenthal, MD, PhD
Associate Professor of Cardiology
Sheba Medical Center, Tel Hashomer, Israel

2. Ehud Schwammenthal, MD, PhD
DISCLOSURES
Ehud Schwammenthal, MD, PhD
Consulting Fees
Medtronic CardioVascular, Inc.
Honoraria
The Engager device is not commercially available in any geography and only available for Clinical Study in the EU

3. Medtronic Engager Design Concept
Self-expandable transcatheter valve
Minimizes pressure loss at the inlet
Maximizes pressure recovery at the outlet
Optimized fluid dynamic shape (Venturi tube) allows to avoid oversizing of the diameter at annular-leaflet level
Resulting shape – inlet, waist, outlet – creates an optimal anatomic fit facilitating intuitive deployment and axial fixation

4. Venturi Tube Principle
Outlet geometry allowing gradual expansion of streamlines eliminates flow separation and prevents turbulence (pressure recovery)
Abrupt outflow (nozzle): turbulence, head loss
Gradually expanding outflow: eliminates flow separation and recovers the pressure drop
Prandtl L, Tietjens O: Applied Hydro- and Aeromechanics, New York, Dover 1957

5. Valve Hemodynamics
EOA: 1.62 cm2 (5L/min)
Producing the hemodynamics of a 23 valve without oversizing
at the native aortic orifice
(CE Magna 21: 1.48 cm2 , Mitroflow 23: 1.57 cm2)*
*Gerosa et al, The Journal of Thoracic and CV Surgery, May 2006

6. Medtronic Engager Transcatheter Valve
Scalloped bovine pericardial
leaflets
Dedicated commissural posts
Nitinol main
frame
Nitinol support frame
The valve’s outlet section is designed as a regular surgical bioprosthesis
dedicated commissural posts
scalloped bovine pericardial lealfets
not encompassed by a metal stent frame, so that they are folded rather than compressed during valve loading
Polyester skirt 6

7. Medtronic Engager Implantation

8. Shape creates anatomical fit: positioning and fixation
Medtronic Engager
Shape creates anatomical fit: positioning and fixation
Shape facilitates implementation of a periannular anchoring system for intuitive and accurate deployment, anatomical positioning and axial fixation
The native leaflets are embraced between an inlet and a 3D support frame tracking the shape of the aortic root
Arms at the floor of the sinuses, prosthetic commissural posts riding astride the native commissures
Periannular fixation – anatomically correct supraannular position

9. Shape creates anatomical fit: positioning and fixation
Medtronic Engager
Shape creates anatomical fit: positioning and fixation
Native leaflets are prevented from being pushed against coronary ostia.
Native leaflets held against the mainframe and thus recruited to seal off potential perivalvular regurgitation.
Native leaflets are kept below the prosthetic leaflets, allowing the prosthetic leaflets to interact with the natural vortex flow in the sinuses for optimal closing. α
Design (shape) causes support arms to maintain a predesigned angle upon deployment

10. Medtronic Engager Leaflet Kinematics
Leonardo da Vinci B C D A
Gharib M, et al. Exp in Fluids 2003

11. Medtronic Engager Rotational Positioning
RAO R N L 11 11

12. Medtronic Engager Rotational Positioning
LAO R N L 12

13. CRL 1. Establish delivery axis as the commissure between 2 sinuses
2. Align window of prosthetic commissural post with native one
LCS
RCS
CRL
Delivery Axis
Commissure is the tip of the intercusp triangle spared by contrast medium

14. Taped Case
3:20

15. Post-Implantation rotational angiography (Dyna CT)

16. FIM: Baseline Characteristics
30 patients, 25 female (83%) and 5 male
Age: 83 ± 4 years
Logistic EuroSCORE: 23±12.0 %
Functional Class: 90% NYHA III and IV
Pressure Gradient: Peak 86±22 mmHg ( )
Mean 52±14 mmHg
Concomitant AR: None - 17% I - 57%, II - 23%, III - 3%

17. FIM: Placement and Hemodynamics
Accurate placement in 29/30 (97%)
No device embolization
Pressure gradient: Peak-to-peak ± 9 mmHg
Peak ± 10 mmHg
Mean 12 ± 6 mmHg
Aortic regurgitation : None or trace % I % I-II 13% II %

18. FIM: Procedural Details
Skin-to-skin time 74 ±16 minutes
Implantation time: 5.9±2.4 minutes
Contrast medium volume: 130±58 ml
Fluoroscopy time: 7.5±2.6 minutes
Mention only means
Contrast medium 330ml first case
PG invasively measured… and the corresponded mean pressure…
AR – up to %, no grade 3 or 4

19. FIM: Procedure Outcome
No coronary obstruction
No stroke or myocardial infarction
PM implantation for AV conduction blocks 3/30
Mortality at 30 days 20%, all non-device related (No perioperative mortality in the last 12 cases)
Conversion to surgery for aortic dissection: 3/30

20. General Misconception
“[Access to] the aortic valve from the left ventricular apex is straight and relatively short”, Dewey TM, Walther T, Mack MJ, et al Ann Thorac Surg 2006 and 2009
LAO

21. LAO view creates impression of relatively straight access.
BUT, the ventriculo-aortic angle can be appropriately appreciated only in the RAO view.
RAO equiv
LAO equiv

22. Learned to use RAO to guide adjustment of delivery angle (correct misplacement of support arm below NCS if needed)
Before
After

23. Learned to use of RAO to monitor advancement of delivery catheter to avoid injury to aortic wall

24. Learnings from Feasibility Study: Need for Delivery System Improvements
Flexible over-the-wire design (forgiving)
Full coverage of commissural posts to protect aorta until device is positioned
Mechanism for release of support arms that does not require advancing the delivery catheter further into aorta
Converted delivery into one-piece system (no need for exchange of dilator) to streamline procedure

25. Summary – Medtronic Engager
Self-guided, reproducible and intuitive deployment into an anatomically correct position
Relies on axial in addition to radial forces for fixation
Leaves the coronary ostia unobstructed and accessible
Reduces the risk of perivalvular regurgitation
Applies proven surgical design standards for long-term durability
Enhancements of the delivery system are under way in preparation of EU Pivotal Trial (2010)

26. Thank You !