Stentless BioprosthesesThird International Symposium

(1)

ECHO DOPPLER EVALUATION OF STENTLESS BIOPROSTHETIC VALVES.

Data from two different models in 80 stable, ambulatory patients

Stentless Bioprostheses

Third International Symposium

P Menu, P Corbi, C Coudrec, E Donal,D Coisne, J Allal,

D Herpin

Grand Cayman May 12-16 , 1999

(2)

Introduction

• Homografts have been known for their superior hemodynamics in aortic valve replacement and

longer durability, but their use is usually restricted because of their limited availability

• The goal of the stentless aortic xenografts is to achieve the same results as homografts with no availability problem.

Stentles Bioprostheses Third International Symposium 1999

(3)

Objective

• A Doppler echocardiographic study was performed to compare the hemodynamic performance after aortic valve replacement using two porcine stentless valves with

different preservation techniques.

(4)

Materials and methods

Pts (n)

Average age (years)

Female (n)

NYHA preope

rative

Sinus

rhythm BSA

(m2) Average of mean gradient (mm Hg) Group I

Freestyle Medtronic

42 69.5 15/42 3.1

^{37 sr}

5^DDD

1.76

^62.4

(47/91)

Group II Prima Baxter

38 69.8 15/38 3.2

^{35 sr}

3 DDD

1.72

^66.5

(53/101)

Between January 1995 and October 1998, 80 patients underwent AVR, there were no differences between the two groups.

(5)

Operative data

Freestyle

^SD

Prima

^SD

Average Aortic valve size

25.1 1.8 24.8 1.9

Concomitant CABG (n(%)

8(19) 12(31.5)

Associated procedures

3 1

Average aortic clamp time

All (min)

92.8

^15.4

90.1

^16.3

Aortic clamp time without

CABG (min)

77.6

^13.2

74.4

^14.8

Minimally invasive

technique (n)

5 1

Techniques Freehand/

miniroot

38/4 37/1

(6)

Techniques ( steps 1 , 2 and 3)

• Cardiopulmonary bypass is established with an ascending aortic cannula and a one-stage venous cannula

• Anterograde blood cardioplegia is used

• The aorta is opened using a transverse incision above the sinotubular junction and always at least 10mm above the origin of the right coronary

artery

• Meticulous decalcification, and debulking of the native annulus and the commisural areas was

carried out

(7)

Techniques ( sizing and implant)

• It is particulary important not to distort the inflow aspect of the valve

• And to size the annulus and the sinotubular junction

• A valve 1-2 mm larger than the exact measurement was selected

• The inflow sutures were applied to the aortic annulus with respect to the scalloped line except for the three sutures on the commissures.

• A double-armed Prolene suture was first taken to the surgeon's right, attaching the outflow portion of the stentless to the crest of the native aorta

(8)

Operative data

4 7

11 15

12 11 11

9

0 2 4 6 8 10 12 14 16

size 21 size23 size 25 size27

Prima Freestyle

(9)

Body surface area / valve sizes

0 0

5 5 8

9

10 9

0 1 2 3 4 5 6 7 8 9 10

21 23 25 27

Prima Freestyle

4 7

6 10

4 2

1 0 0

1 2 3 4 5 6 7 8 9 10

21 23 25 27

1.70m2 and <1.85 m2 > 1.85 m2

(10)

Results :

Three hospital deaths occured

• Female /80/ NYHA III/ LVEF= 61 % BS 1.68

• Freestyle 21 /97 mn Ao Cl Time.

• MOF

• Male / 84 /NYHA III/ LVEF=48% / severe COPD

• Prima 23/ / ACCT 78

• Pulmonary infection/Respiratory Failure Male / 54 / LVEF < 15 %/ LVTD 72mm Prima 27/ ACCT 67

Sudden death at day +7 by Ventricular Fibrillation

(11)

STS ’s Guidelines

Endocar ditis

Myoca rdial infarcti on

Minor Throm boemb olism

Major Throm

Reopera tion

Second ary deaths

Structu ral

failure

Free 1 0 0 1 0 1 0

Prima 0 1 1 0 1 0 0

(12)

Serial echography for the two groups

72

8

74

1

31

9 8

2 0

10 20 30 40 50 60 70 80

per-op 6/12 months 24 months 36months Doppler No exam

Two-dimension directed LV M-mode echocardiograms were recorded per/post-operatively, 6, 12, 24, 36 months after AVR

(13)

The mean transvalvular gradients

Post operatively At 1 year

Type Freestyle Prima Freestyle Prima

Size (mm)

n Mm Hg

SD n Mm Hg

SD n Mm Hg SD

21 7 15.5 5.4 4 17.2 4.4 6 10.4 3.3 4 11.3 5.7 23 15 13.2 3.9 11 10.8 3.6 14 9.2 3.4 10 8.4 3.9 25 11 11.1 4.1 12 10.4 5 10 8.2 4.3 11 7.9 4.5 27 9 8.2 2.7 11 8.6 2.7 9 7.7 2.2 11 6.6 3.4

(14)

Evolution of aortic insufficiency

Trivial Mild Severe At Discharge 11 Pts 2 Pts 0

At 24 months

10 1 Pt 1 Pt

24

The patient with a prosthesis 27 had been reoperated

(15)

Case report of the reoperation

• Female 76 old

• Aortic insufficiency

• Mild ascending aorta dilatation (34mm)

• Stentless 27 Prima+CABG2

• Post-op Doppler AI 1/4

• 12 months later AI 3/4

(16)

Case report of the reoperation

• At the reoperation, the ascending aorta was dilated 38 mm

• The enlargement of the sinotubular junction explained the aortic

insufficiency

• The valve itself was free from of any calcification or strutural dysfunction

(17)

At the end of reoperation:

Stented CEP N°27

Outcome with no problem

(18)

Left ventricular remodeling

• "After stentless aortic valve replacement, LV mass index and wall thickness both fall

towards normal.

• These ventricular remodeling processes are accompanied by a more physiological flow jet at valve cusp level, so that effective

orifice area increases."

X Y Jin, S Westaby, D G Gibson

European Journal of Cardio-thoracic Surgery 12 (1997) 63-69

(19)

Conclusion I

• Mean transvalvular gradients progressively decreased from the immediate post-

operative values to values measured at 12 months

• The reduction in residual gradient and potential regression in left ventricular

hypertrophy may have beneficial prognostic

implications

(20)

Conclusion II

• Our experience suggests that stentless

valves implanted by the freehand technique are not indicated for Aortic insufficiency with dilatation of ascending aorta but are

perfect for aortic stenosis and especially for small aortic annulus.

(21)

Lv mass index

Freestyle Prima

Size N Pre 1 Year V N Pre 1 year v

21/23 22 139.1 117.9 -21.2 15 139.4 117.7 -21.7

25/27 20 141.3 123.1 -18.2 23 140.8 124.1 -16.7