10 Versus 20 Minutes Treatment of Human Pericardium With Glutaraldehyde in OZAKI Procedure

Study Overview
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Brief Summary
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To compare mechanic and thermic stability of pericardium fixated either with 0.6% glutaraldehyde for 10 minutes or with 0.6% glutaraldehyde for 20 minutes

Detailed Description
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Autologous pericardium for aortic valve reconstruction is treated with 0.6% glutaraldehyde for 10 minutes to improve stability (OKAZI technique). This study investigates whether treatment with 0.6% glutaraldehyde for 20 minutes improves mechanic and thermic stability of autologous pericardial tissue. Autologous pericardium remaining after aortic valve reconstruction surgery is used. To investigate 10 versus 20 minutes treatment of removed original aortic valve tissue with glutaraldehyde as a reference.

Official Title
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10 Versus 20 Minutes Treatment of Human Pericardium With Glutaraldehyde in OZAKI Procedure

Conditions
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Aortic Valve Surgery

Intervention / Treatment
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* Other: Treatment of human pericardium with glutaraldehyde in OZAKI procedure
* Other: Treatment of human aortic valve tissue with glutaraldehyde


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing aortic valve surgery with sufficient leftover tissues from the OZAKI procedure (excess of pericardium and calcified aortic valve leaflets) Exclusion Criteria: denial of consent insufficient leftover tissues from the OZAKI procedure patients after thoracic radiation or surgery
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Treatment of human pericardium with glutaraldehyde in OZAKI procedure|10 versus 20 minutes treatment of human pericardium with 0.6% glutaraldehyde in OZAKI procedure|
|Other: Treatment of human aortic valve tissue with glutaraldehyde|10 versus 20 minutes treatment of human aortic valve tissue with 0.6%glutaraldehyde|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| mechanic stability tests to investigate uniaxial and cyclical tensile properties | mechanical tests include the use of a universal test machine (MTS Bionix, Department of Bioengineering of Universitaetsspital Basel) for: uniaxial ultimate tensile strength (UTS) test; cyclical tensile stretching of the tissue in order to investigate its viscoelastic properties | 4 days after surgery | 
| thermic stability by using constant force at linearly increasing temperature | constant force at linearly increasing temperature: Thermal stability tests will be conducted on 20 x 4 mm stripes by the imposition of a constant load (approximately 1N) submerged in a saline-solution bath. The temperature of the bath will be increased at a rate of approximately 2.5-5 °C/min, and the sample cross-section will be measured by means of a high-resolution camera (Canon EOS, Japan) | 4 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| histologic analysis of collagen fiber organization and quantification | histologic analysis by Scanning Electrical Microscopy (SEM) and using Picrosirius staining to identify the types I and IV collagen | 4 days after surgery | 
| Pronase testing to analyse enzymatic degradation | Pronase testing to analyse enzymatic degradation | 4 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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OZAKI technique