Aspirin and Thienopyridine Resistance in Peripheral Arterial Disease

Study Overview
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Brief Summary
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This study evaluates the effects of Aspirin and thienopyridine resistance in relation to clinical cardiovascular outcomes as the genetic predictors of, and outcomes associated with aspirin and thienopyridine resistance in patients with peripheral arterial disease (PAD) currently remain unknown.

Detailed Description
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Although anti-platelet therapy is a cornerstone of PAD treatment, the investigators know very little about the prevalence, genetic determinants and clinical relevance of aspirin and thienopyridine resistance in PAD patients. The investigators expect to report on the prevalence of, and impact on outcomes from aspirin and/or thienopyridine (eg. clopidogrel) resistance, in patients who undergo peripheral arterial angiography/interventions (including carotid angiography/interventions) and operations. This study will provide important information on the utility of testing for aspirin and thienopyridine resistance and improve understanding of the genetic and pathophysiologic basis of anti-platelet therapy resistance in patients with cardiovascular disease, including PAD. Most importantly, this study will serve as the basis for a subsequent randomized prospective trial of different treatment options in PAD patients with aspirin/thienopyridine resistance.

Official Title
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The Effect of Aspirin and Thienopyridine Non-responsiveness on Outcomes in Peripheral Arterial Disease

Conditions
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Peripheral Arterial Disease, Clopidogrel, Poor Metabolism of

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient undergoing PAD (carotid or lower extremity) angiography or intervention greater than or equal to 18 years of age Exclusion Criteria: patient unable to take aspirin and thienopyridine for any reason (not excluded if take at least one of either medication) hematocrit less than or equal to 30% hematocrit greater than or equal to 52%

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Aspirin responsive<br>The participant is shown to be responsive to platelet activity inhibition by aspirin, as determined by testing with VerifyNow | |
| Aspirin non-responsive<br>The participant is shown to be non-responsive to platelet activity inhibition by aspirin, as determined by testing with VerifyNow | |
| Clopidogrel responsive<br>The participant is shown to be responsive to platelet activity inhibition by clopidogrel, as determined by testing with VerifyNow | |
| Clopidogrel non-responsive<br>The participant is shown to be responsive to platelet activity inhibition by clopidogrel, as determined by testing with VerifyNow | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clopidogrel non-responsiveness | Clopidogrel non-responsiveness was defined as patients with Plavix reaction units (PRU) ≥ 235 | Immediate | 
| Aspirin non-responsiveness | Aspirin non-responsiveness was defined as patients with aspirin reaction units (ARU) ≥ 550 | Immediate | 
| Composite of major adverse cardiovascular events | Composite of major adverse cardiovascular events including all-cause mortality, myocardial infarction, stroke, target vessel revascularization (TVR) and limb loss in patients who underwent extremity intervention. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Genetic predictors of aspirin and clopidogrel non-responsiveness | Single nucleotide polymorphisms (SNP) were correlated to measures of aspirin and clopidogrel non-responsiveness | Immediate | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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aspirin, clopidogrel, peripheral arterial disease, genetics