Von Willebrand Factor As a Biological Sensor of Blood Flow in Percutaneous Cardiac Procedure

Study Overview
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Brief Summary
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The WITAVI study was designed to explore the kinetic and associated outcome of Von Willebrand Factor-multimerizaton defects associated with devices in cardiovascular diseases.

Detailed Description
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This study was designed to understand the Von Willebrand Factor (VWF) abnormalities observed in association with implantation of different devices in cardiovascular diseases (percutaneous valve replacement and circulatory support devices). The main objective of the study was to describe the time-course of VWF abnormalities onset/offset during implantation of devices in cardiovascular diseases. Adult patients > 18 years who need a CF-LVAD or trans-aortic valve implantation are included in this cohort; Blood samples are obtained just before procedures

Official Title
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Onset and Offset of Von Willebrand Factor Multimemirization Defects in Cardiovascular Disease: the Case of the Molecular Sensor of Blood Flow

Conditions
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Heart Failure, Aortic Stenosis

Intervention / Treatment
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* Device: cardiac devices


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients > 18 years who need a mechanical circulatory support due to advanced heart failure or undergoing trans-aortic-valve-replacement to treat aortic stenosis. Informed consent of the patient or support person in case of disability at baseline (patient intubated and ventilated) Exclusion Criteria: Patient with a known severe bleeding disorder Patient refusal or environment Minor patients Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| cardiac devices<br>patients receiving mechanical circulatory support patients undergoing transaortic valve replacement | Device: cardiac devices<br>* patients receiving mechanical circulatory support or undergoing trans aortic valve replacement<br>* Other names: mechanical circulatory support;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Von Willebrand factor (VWF) multimer defects | VWF multimeric analysis is performed by electrophoresis. The results of HMW-multimers are expressed as the relative amount of the largest multimers (mer>15) of the sample compared with those of the normal pooled plasma (NPP standard human plasma Siemens healthcare diagnostics, Marburg, Germany, coefficient of variation=11%) present on each gel. 4-6 With this method the HMW-multimer ratio is defined as the HMW-multimers (>15-mer) in patient plasma sample divided by HMW-multimers in normal pool plasma, the HMW-multimer ratio of normal pooled plasma is 1 (by definition) and an HMW-multimer defect is defined as a reduced HMW-multimer-ratio (<1). | 180 minutes after device implantation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| platelet function analyser- ADP (PFA-ADP) closure time | The PFA test is initially performed with the Collagen/Epinepherine membrane. A normal Col/ADP closure time (<180 seconds) excludes the presence of a significant platelet function defect. | 5, 15,30, 60 minutes; day 1 , day 7 after device implantation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acquired Von Willebrand, Trans aortic valve replacement, mechanical circulatory support