Prosthetic Aortic Valve
Endocarditis – Are Homografts
Superior?
2015 AATS Cardiovascular Valve Symposium
November 21, 2015
Sao Paulo
Thoralf M. Sundt, MD
Edward D. Churchill Professor of Surgery
Chief Division of Cardiac Surgery
Disclosure
• Scientific advisor for Thrasos
2
But there is a problem: Homografts calcify
6
Are homografts necessary?
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Of 383 patients with active endocarditis
135 with paravalular abscess
66 with prior prosthetic
All treated with patches and conventional valves
Are homografts necessary?
8
Of 383 patients with active endocarditis
135 with paravalular abscess
66 with prior prosthetic
All treated with patches and conventional valves
Are homografts necessary?
- 127 pts
- 50% w
abscess
- 43%
homograft
- 57%
conventiona
l
Are homografts necessary?
homograft
conventional
- 127 pts
- 50% w
abscess
- 43%
homograft
- 57%
conventiona
l
Are Homografts necessary?
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Are homografts necessary?
12
134 patients with active endocarditis
90 with prior prosthetic AVR
100 with abscess
43 mechanical valve-conduit
55 bio-root
36 homograft
No difference in freedom from
reoperation
Are homografts necessary?
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1161 patients with active endocarditis
-172 with root abscess
-76 with prior prosthesis
-Repaired with patches and conventional
prostheses
Special Case of Infection: Homograft or Dacron?
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Use of synthetic material had no
adverse impact on freedom from
reoperation after homograft root
reconstruction for “true redo-root”
Special Case of Infection: Homograft or Dacron?
15
43 mechanical valve-conduit
55 bio-root
36 homograft
No difference in freedom from
reoperation
Are Homografts Superior to Prosthetic Valves in
the Setting of Infective Endocarditis?
Joon Bum Kim1, Julius I. Ejiofor2, Maroun Yammine2, Janice M. Camuso2, Conor
W. Walsh3, Serguei I. Melnitchouk1, James D. Rawn2, Marzia Leacche2, Thomas E.
MacGillivray1, Lawrence H. Cohn2, John G. Byrne2, Thoralf M. Sundt1
Methods
• Data were pooled from the prospective cardiac surgery
databases of two Harvard Medical School affiliated
Hospitals: MGH and BWH
• Queried to identify adult patients (age ≥ 17 years)
undergoing AV operations due to active infective
endocarditis from January 2002 through August 2014
Methods
• Follow-up information:
Data from Partners Health Care system
( centralized clinical data registry of all patients encountered)
• Social Security Death Index search if necessary
• IRB approval: waived informed consent
Subject Patients
• There were 304 patients who met the enrollment criteria
from the two centers (MGH, n=141; BWH, n=163).
• Homograft: n=86 (28.3%)
• Xeno-prostheses: n=79 (26.0%)
• Mechanical prostheses: n=139 (45.7%)
Baseline Characteristics
Homograft
(n=86)
Mechanical
(n=79)
Xenograft
(n=139)P value
Age, yr 55.6±16.6 47.2±14.5 59.8±14.6 0.001
Male gender 73.3% 75.9% 75.5% 0.91
IV drug user 17.4% 20.3% 11.5% 0.19
DM, insulin therapy (-) 10.5% 5.1% 12.2% 0.23
DM, insulin therapy (+) 5.8% 2.5% 9.4% 0.14
Current smoking 17.4% 12.7% 11.5% 0.43
NYHA functional class III/IV 54.7% 34.2% 53.2% 0.011
Serum creatinine, mg/dL 1.32±0.71 1.56±1.47 1.52±1.03 0.15
Age, yr 55.6±16.6 47.2±14.5 59.8±14.6 0.001
NYHA functional class III/IV 54.7% 34.2% 53.2% 0.011
Baseline Characteristics
Homograft
(n=86)
Mechanical
(n=79)
Xenograft
(n=139)P value
Cerebral embolic events 26.7% 12.7% 25.9% 0.046
Bacteriology 0.002
Viridans Streptococci 14.0% 38.0% 25.2%
Other Streptococci 10.5% 3.8% 11.5%
MS-Staphylococcus 17.4% 8.9% 19.4%
MR-Staphylococcus 25.6% 12.7% 11.5%
Entercococcus 12.8% 13.9% 18.7%
Other 9.3% 7.6% 8.6%
Negative culture 10.5% 15.2% 5.0%
Cerebral embolic events 26.7% 12.7% 25.9% 0.046
Bacteriology 0.002
MR-Staphylococcus 25.6% 12.7% 11.5%
Viridans Streptococci 14.0% 38.0% 25.2%
Baseline Characteristics
Homograft
(n=86)
Mechanical
(n=79)
Xenograft
(n=139)P value
Multiple valves affected 16.3% 41.8% 20.9% <0.001
Severe valve dysfunction 57.0% 72.2% 77.0% <0.001
Vegetation diameter>10mm 41.9% 54.4% 47.5% 0.27
Abscess formation 67.4% 40.5% 29.5% <0.001
Prosthetic endocarditis 58.1% 39.2% 21.6% <0.001
LVEF, % 57.8±11.9 60.1±9.5 60.0±11.6 0.17
Emergency surgery 28.3% 22.8% 45.7% 0.91
Preoperative IABP 5.8% 6.3% 3.6% 0.61
Multiple valves affected 16.3% 41.8% 20.9% <0.001
Severe valve dysfunction 57.0% 72.2% 77.0% <0.001
Abscess formation 67.4% 40.5% 29.5% <0.001
Prosthetic endocarditis 58.1% 39.2% 21.6% <0.001
Procedural Characteristics
Homograft
(n=86)
Mechanical
(n=79)
Xenograft
(n=139)P value
Associated procedures
Aortic root replacement 98.8% 19.0% 10.8% <0.001
Aorta replacement 18.6% 13.9% 19.4% 0.58
CABG 34.9% 20.3% 10.1% 0.022
CPB time, min 318.2±146.5 235.0±129.4 181.4±136.6 <0.001
ACC time, min 236.1±100.7 177.1±91.7 136.8±89.5 <0.001
Aortic root replacement 98.8% 19.0% 10.8% <0.001
CPB time, min 318.2±146.5 235.0±129.4 181.4±136.6 <0.001
ACC time, min 236.1±100.7 177.1±91.7 136.8±89.5 <0.001
Follow-up
• Data on mortality: 100% complete
- Median, 52.4 months (IQR, 14.5-99.1 months)
• Data on valve-related complications: 75.7% complete
- Median, 29.4 mo (IQR, 4.7-72.6 mo)
Early Outcome
• Early mortality rate
- Homografts: 19.8% (17/86)
- Mechanical valves: 12.7% (10/79)
- Xenografts: 7.2% (10/139)
P=0.22
P=0.005
Survival
Reinfection
Event-free survival
Propensity Score Adjustment
• Homograft (N=86) vs. Conventional prostheses (N=218)
• Propensity score: logistic regression based on 27 variables
• Propensity score=“probability of receiving homograft”
• Inverse-Probability-Treatment-Weighting (IPTW):
Weight=“1/PS” in Homograft group
Weight=“1/(1-PS)” in Conventional group
Propensity Score Adjustment
Baseline P
values: 0.48-
0.98
Conventional
prostheses
Homograft
Survival: Adjusted
Reinfection: Adjusted
Event-Free Survival: Adjusted
Adjusted Outcomes: Summary
HR 95% CI P value
Early mortality 1.61 0.73-3.40 0.23
Overall mortality 1.35 0.79-2.31 0.28
Valve-related events 0.80 0.43-1.48 0.47
Reinfection 1.04 0.49-2.18 0.93
Valve reoperation 1.57 0.70-3.52 0.28
Thromboembolism 0.20 0.03-1.22 0.082
Anticoagulation-related bleeding 0.12 0.01-1.78 0.13
Death + valve-related events 1.16 0.76-1.78 0.49
Adjusted Outcomes
PVE Subgroup: N=111
HR 95% CI P value
Early mortality 1.88 0.69-5.24 0.22
Overall mortality 1.43 0.69-2.95 0.33
Valve-related events 0.70 0.22-2.26 0.55
Reinfection 0.76 0.11-5.53 0.79
Valve reoperation 0.60 0.10-3.71 0.59
Thromboembolism NA NA NA
Anticoagulation-related bleeding 0.41 0.04-4.30 0.45
Death + valve-related events 1.34 0.72-2.51 0.36
Limitations
• Retrospective analyses
• Selection bias
• Potential residual confounding caused by unmeasured
covariates
• Significant follow-up loss
Conclusions
• No significant benefits of homograft over standard prosthetic
valves were demonstrated in the setting of IE affecting AV
with regard to reinfection or survival.
• Patient specific factors (i.e. preferences/technical) should be
the principle drivers of choices of valve prostheses.
• Lack of access to homografts should not be considered an
obstacle to surgical therapy for this grave condition.
Outcomes
No. of Events (%)
IVDA Non- IVDA P value
Early mortality 3.8% 13.7% 0.012
Overall mortality 17.9% 22.3% 0.39
Valve related complications 41.0% 10.3% <0.001
Valve Re-infection 35.9% 3.9% <0.001
Valve reoperation 23.1% 4.7% <0.001
Thromboembolism 9.0% 2.8% 0.019
Hemorrhage 6.4% 3.1% 0.18
Composite endpoint 50.0% 29.3% 0.004
Follow-up: 76.4% completeMedian, 29.4 mo (IQR, 4.7-72.6 mo)
Overall Survival
Freedom from
Reinfection and Reoperation
Age-Adjusted Outcomes
IVDAs vs. Non-IVDAs
Adjusted
HR 95% CI P value
Early mortality 0.53 0.11-1.78 0.34
Overall mortality 1.37 0.68-2.74 0.38
Valve related complications 3.07 1.66-5.68 <0.001
Valve Re-infection 5.36 2.37-12.13 <0.001
Valve reoperation 2.99 1.31-6.79 0.009
Thromboembolism 2.03 0.58-7.02 0.27
Hemorrhage 2.46 0.57-10.61 0.23
Composite endpoint 2.33 1.44-3.78 <0.001
Choices of Prostheses for IVDAs
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