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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