PATIENT PROSTHESIS MISMATCH

1. Factors Affecting Survival After Mitral Valve Replacement
With Prosthesis–Patient
Mismatch
Presenter- Dr. JYOTINDRA SINGH
in
Patients

2. INTRODUCTION

4. GOA for any given bioprosthetic
valve is here defined as the area of
the valve at its greatest opening.
This is a valid approximation
because the GOA of a bioprosthetic
heart valve changes little during
systole.

7. BACKGROUND
Obviously, the best way to avoid PPM
in the mitral position would be to repair
rather than to replace the valve.
Unfortunately, the options for
preventing PPM in the mitral position
are much more limited than in the
aortic position.
In particular, no alternative technique
exists to implant a larger prosthesis,
and the implantation of a homograft or
of a stentless prosthesis is technically
more demanding and associated with
poor long-term durability.
Hence, the preventive strategy can be
oriented only toward the implantation
of a prosthesis having a larger EOA for
a given annulus size.
2

8. PATHOPHYSIOLOGY
Hence, PPM in the mitral position can be equated to residual mitral stenosis with
similar consequences (ie, the persistence of abnormally high mitral gradients and
increased left atrial and pulmonary arterial pressures).
The major consequence of pulmonary hypertension is right ventricular failure,
which generally results from chronic pressure overload and associated volume
overload with the development of tricuspid regurgitation.
The persistence of high left atrial pressures may predispose to atrial fibrillation.
This arrhythmia may compromise cardiac output and increase the incidence of
thromboembolic complications.
The passive elevation in pulmonary capillary pressure caused by elevated left atrial
pressure also may lead to the development of pulmonary edema.
Consistently, Masuda et al found that the maximum transprosthetic flow velocity is a
strong determinantof the pulmonary capillary wedge pressure in children with
mitral prostheses

9. OBJECTIVE
Objective -The purpose of the current
investigation was to
identify patient subgroups in which PPM most influenced outcome
after MVR, specifically examining the impact of patient age and
prosthesis type on long-term survival.
Place of study- Division of Cardiothoracic Surgery,
Washington University School of Medicine, St. Louis, Missouri
Period of study- (May 1992 to June 2008)

10. Materials & Methods
N=765
500
AGE PROFILE
460
450
400
350
>65yrs
305
370
300
250
AGE
PROFILE
N=765
200
150
< 65yrs
100
50
0
MEN
WOMEN
395

11. Patient profile
valve profile
500
440
450
400
350
325
300
250
200
150
100
50
0
valve
profile

12. Materials & Methods
30
Indication %
26
40
30
20
10
0
37
25
27
23
20
18
15
11
11
7
10
% Concomitant
surgery
8
5
1
0

13. Valve profile
Valve size used %
100
90
30
30
24
80
62
20
60
bioprosthetic
50
mechanical
15
15
%
76
10
30
20
28
25
70
40
27
38
5
10
0
0
<65 yrs >65 yrs
23 to 27 mm 29mm 31 to
25mm
33 mm

14. PPM CRITERIA

15. Type of valve implanted
appears normal

16. RESULTS- PPM EVALUATION
Overall PPM
68
70
50%
45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
60
49%
50
45
37%
40
30 32
30
14%
SEVERE
25
MECHANICAL
20
Bioprosthetic
MODERATE
ABSENT
10
0
2

17. Age based evaluation of PPM
Prosthesis–patient mismatch was less common
with mechanical valves than with biomechanical
Moderate or severe PPM was more common in
women and patients with endocarditis, diabetes,
and chronic renal disease.
Ejection fraction was similar among groups, as
was the percentage of patients with an ejection
fraction of 0.35 or less .
With mechanical valves, the incidence of severe
and moderate PPM was higher in younger
patients , but with bioprosthetic valves,
the incidence of PPM was higher in
older patients

18. Independent predictors of Severe PPM
1) Advanced age
2) Diabetes Mellitus
3) Chronic renal disease
4) Bioprosthetic valves

19. Operative Mortality
Overall mortality – 97/765 , 12.7 %
Mortality varied with complexity of the
procedure
Independent predictors Active endocarditis,
chronic renal insufficiency,
peripheral vascular disease,
non rheumatic origin,
concomitant CABG,
urgent or emergent status,
implantation of a bioprosthetic valve
Operative mortality was higher with
severe PPM (24%) compared
with moderatePPM (14% ) or
absent PPM (8%)

20. CT FINDINGS
appears normal

21. LATE SURVIVAL
Of the 668 operative
survivors, there were 265
late deaths;
403 patients were alive at
late follow-up .
Independent predictors of late death
Advanced age,
Earlier operative year,
CRF
Peripheral vascular disease,
Congestive heart failure,
Nonrheumatic origin,
Concomitant CABG,
Lower BSA,
more significant PPM (lower
EOA/BSA)

22. PPM- AGE STRATIFIED( Mechanical Valve)
100%
80%
82%
66%
77%
62%
60%
5 yrs
10 yrs
40%
20%
0%
Without
PPM
With
PPM
70%
60%
50%
40%
30%
20%
10%
0%
63%
40%
47%
30%
Without
PPM
With
PPM
5 yrs
10 yrs

23. PPM ( Age stratified) – Bioprosthetic VALVE
60%
50%
40%
30%
20%
10%
0%
58%
48% 51%
42%
5 yrs
10 yrs
Without
PPM
With
PPM
45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
43%
30%
21%
5yrs
10 yrs
0%
Without
PPM
With
PPM

24. Comments
“platelet and fibrin deposition, inflammation,
granulation tissue, and finally encapsulation.
Longterm device fibrous encapsulation with
extension to adjacent tissues add to structural
stability.
” Bioprosthetic valves undergo morphological
changes of both the tissue material as well as
the supporting structures, which may
contribute to VP–PM.
Fbrous sheath may also encapsulate the
supporting structure of the valve, encroaching
on the PHV orifice and also possibly causing
valve leaflet or disk immobilization .

25. confirm that the lesion is solitary.

26. BIOPSY Vs RESECTION
confirm that the lesion is solitary.

28. Impact of prosthesis-patient mismatch on tricuspid valve regurgitation
and pulmonary hypertension following mitral valve replacement.
Angeloni E, Melina G, Benedetto U, Roscitano A, Pibarot P, .
Sapienza, University of Rome, Department of Cardiac Surgery,
BACKGROUND:
Mitral PPM can be equated to residual mitral stenosis, which may halt the expected postoperative improvement of PH and concomitant
functional tricuspid regurgitation (fTR). Aim of the present study is to evaluate the impact of mitral prosthesis-patient mismatch (PPM) on
late tricuspid valve regurgitation and pulmonary hypertension (PH).
METHODS:
A total of 210 patients undergoing isolated mitral valve replacement (MVR) were investigated. Mitral valve effective orifice area was
determined by the continuity equation and indexed for body surface area (EOAi) and PPM was defined as EOAi≤1.2cm2/m2. Pulmonary
hypertension (PH) was defined as systolic pulmonary artery pressure (sPAP)>40mmHg. Clinical and echocardiographic follow-up (median
27months) was 100% completed. A total of 88/210 (42%) patients developed mitral PPM.
RESULTS:
There were no significative differences in baseline and operative characteristics between patients with and without PPM. At follow-up, the
prevalence of fTR≥2+ (57%vs.22%; p=0.0001), and PH (62%vs.24%;p<0.0001) were significantly higher in patients with PPM. On
multivariable regression analysis, EOAi (p<0.0001) and preoperative left ventricular (LV) end-diastolic diameter (p<0.0001) were found to
be independently associated with fTR decrease after MVR. In addition, EOAi (p<0.0001) and LV ejection fraction (p<0.0001) were
independently associated with PH decrease after MVR. No significant differences in mortality rates were found between patients having or
not PPM.
CONCLUSIONS:
This study shows that mitral PPM is associated with the persistence of fTR and PH
following MVR. These findings support the realization of tricuspid valve annuloplasty
when PPM is anticipated at the time of operation.

31. EOAi should be measured at 1 to 4 weeks or at hospital discharge to evaluate the
actual valve size that wasimplanted. This should also be done at 6 to 12 months to
evaluate the severity of VP–PM that will affect long-term outcomes.
The grading of severity of VP–PM should be similar to another common LV outflow
tract obstruction, namely,valvular AS.
.To assess the effects of VP–PM on mortality, the goal should be to determine by
multivariate analysis the role of VP–PM on mortality due to cardiac causes .
The primary goal should be not to prevent VP–PM but rather to prevent severe VP–
PM.
Use of the EOAi as a continuous variable may help to define the level of severe
VP–PM that results in increased mortality, and this may occur at a critical level of
obstruction

32. 3 STEP PROTOCOL
was elaborated by Pibarot and Dumesnil
1) calculate the BSA using the Dubois method;
2) determine the minimum EOA required to ensure an EOAi of 1.2 cm /m2 based on the
minimum required EOAi for a given patient;
3) select the type and size of the valve greater or equal to the minimal EOA value obtained
in step 2.
Although annular size is never a problem with ischemic regurgitation, for rheumatic patients with
mitral stenosis, partial posterior leaflet resection with pseudochord placement to
maintain 3 papillary-annular continuity may be an option to make room for a bigger prosthesis.
In contrast, patients with a heavily calcified, restricted mitral annulus may be at the
mercy of valve selection, unless one wishes to embark on a complex annular decalcification
procedure.
Oversizing the valve can lead to disastrous complications, including disruption of the
atrioventricular groove.