Brief Title
Study of Platelet Activation by Severe Aortic Stenosis and Its Correction by Transcatheter Aortic Valve Implantation
Official Title
Study of Platelet Activation by Severe Aortic Stenosis and Its Correction by Transcatheter Aortic Valve Implantation (TAVI) Platelet Activation in TAVI
Brief Summary
Study of platelet activation by severe aortic stenosis and its correction by Transcatheter Aortic Valve Implantation (TAVI)
Detailed Description
- Background: TAVI has emerged as an alternative to surgical aortic valve replacement for patients with severe, symptomatic aortic stenosis (AS) and is expanding worldwide with more than 50,000 patients treated to date. - Purpose Changes in haemostasis, particularly in platelet activation or reactivity before, during and after TAVI have never been studied. Valve replacement is known to alleviate von Willebrand factor abnormalities associated with AS. A potential improvement of platelet function could also occur after TAVI. Indeed, circulating platelets may be desensitized and under-reactive due to multiple passages through the stenotic valve and could recover normal reactivity after TAVI. Besides, TAVI presents a risk of major ischemic complications. The investigators can hypothesize the involvement of high reactive platelets in peri-procedural thrombotic or ischemic events. This study of the platelet activation kinetics will be performed by comparing several specific markers before and at various times after valve implantation. - Primary outcome To evaluate the kinetics of platelet activation before and at various times after valve implantation, by comparing several specific markers in peripheral venous blood samples before (day 0) and at days 1 and 5±1 after the procedure. - Study design and number of subjects: This is a prospective, monocentric, study. The test group includes up to 15 patients treated by transfemoral TAVI using a MedTronic CoreValve (MCV) prosthesis. Platelet activation will be studied before and after the procedure and compared to a reference established with an age-matched, aspirin-treated, atherosclerotic population (30 patients in the control group). - Eligibility criteria: - inclusion criteria: test group: patients with severe aortic stenosis and transfemoral TAVI with MCV aspirin treatment . Control group: age-matched patients with stable coronary artery disease treated by aspirin but without aortic stenosis. - exclusion criteria: recent (1 month) acute coronary syndrome; treatment by anti platelet agents other than aspirin - Procedures: Specific platelet activation markers, circulating platelet/monocytes aggregates, platelet reactivity and vWF will be assessed in peripheral venous blood before, 1 and 5 days after TAVI and in ascending aorta during the procedure.
Study Type
Interventional
Primary Outcome
the change of kinetics of platelet activation
Secondary Outcome
Changes of platelet activation
Condition
Aortic Stenosis
Intervention
test
Study Arms / Comparison Groups
test group
Description: Patient with severe, symptomatic AS (Aortic valve area < 0,6 cm2/m2 SC), deemed, after multidisciplinary heart team evaluation, contra-indicated or at high risk for surgery and suitable for TF TAVI with a MCV prosthesis.
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Recruitment Status
Other
Estimated Enrollment
44
Start Date
May 2014
Completion Date
October 2015
Primary Completion Date
October 2015
Eligibility Criteria
Inclusion Criteria: - Test group - Severe symptomatic AS (Aortic valve area < 0,6 cm2/m2 SC), deemed, after multidisciplinary heart team evaluation, contra-indicated or at high risk for surgery and suitable for TF TAVI with a MCV prosthesis. - Aspirin treatment (75-160 mg/d for at least one week) - Control group - Stable coronary artery disease, unscathed of AS - Aspirin treatment (75-160 mg/d for at least one week) Exclusion Criteria: - Test group: - Acute coronary syndrome 1 month before inclusion - Any co-morbidity limiting life-expectancy < 1 year - Terminal chronic kidney disease requiring hemodialysis thrombocytopenia <100 G/L, anemia (Hb < 10 g/dl) - Treatment by another antiplatelet agent within 10 days before the procedure - Control group: - Acute coronary syndrome 1 month before inclusion - Any co-morbidity limiting life-expectancy < 1 year - Terminal chronic kidney disease requiring hemodialysis - Thrombocytopenia <100 G/L - Treatment by another antiplatelet agent within 10 days before the procedure
Gender
All
Ages
50 Years - N/A
Accepts Healthy Volunteers
No
Contacts
Pierre SIE, MD PhD, ,
Location Countries
France
Location Countries
France
Administrative Informations
NCT ID
NCT02504632
Organization ID
14 7078 03
Responsible Party
Sponsor
Study Sponsor
University Hospital, Toulouse
Collaborators
Medtronic
Study Sponsor
Pierre SIE, MD PhD, Study Chair, University Hospital, Toulouse
Verification Date
March 2017