Perioperative Aspirin Response in Patients Undergoing Vascular Surgery

Study Overview
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Brief Summary
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Reduced antiplatelet activity (low response (LR)/high on-treatment platelet reactivity (HPR)) of aspirin (ALR) or clopidogrel (CLR) is associated with an increased risk of thromboembolic events. The prevalence figures for low-responders reported in the literature vary widely and there have been few investigations in vascular surgery patients to date. The aim of this prospective monocentric study was to increase the evidence base on vascular surgery patients and to detect any changes in the response following vascular surgery procedures.

Detailed Description
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The activity of aspirin (acetylsalicylic acid, ASA) and clopidogrel is measured by whole blood impedance aggregometry using a multiple electrode aggregometer (Multiplate). The agonists used are arachidonic acid for aspirin and adenosine diphosphate (ADP) for clopidogrel. Vascular patients requiring treatment for peripheral artery disease (PAD) and/or carotid stenosis are included in the study. To identify possible risk factors demographic data, concomitant medication, laboratory parameters, co-morbidities, severity of the condition and the type of procedure performed are documented. In addition, a follow-up aggregometry is performed after completion of the vascular procedure.

Official Title
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Perioperative Risk Factors for the Development of Aspirin Low Response in Patients Undergoing Vascular Surgery.

Conditions
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Vascular Surgery Patient With PAD / Carotid Stenosis

Intervention / Treatment
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* Drug: Whole blood aggregometry before and after vascular treatment (ASA/ Clopidogrel).


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Vascular patients requiring treatment for peripheral artery disease (PAD) and/or carotid stenosis are included in the study. Exclusion Criteria: non-adherence to the antiplatelet medication abnormal platelet count in patients, current gastrointestinal disorders, current infections, serious concomitant medical conditions (such as recent gastrointestinal bleeding, cancer, severe cardiac or liver disorders) known bleeding or coagulation disorders,

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental: aspirin, clopidogrel<br>Perioperative measurement of ASA and clopidogrel resistance in patients undergoing vascular treatment | Drug: Whole blood aggregometry before and after vascular treatment (ASA/ Clopidogrel).<br>* To identify possible risk factors demographic data, concomitant medication, laboratory parameters, co-morbidities, severity of the condition and the type of procedure performed are documented. Other Name: ASA (aspirin), Clopidogrel (Plavix)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants Who Were Responders or Low-Responders of Antiplatelet Therapy as a Result of Whole Blood Aggregometry Testing | In patients treated with aspirin and clopidogrel aggregometry was performed and depending on the results the patients were either responder or low-responder of antiplatelet therapy. | 2 years |