Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT01329224 |
| Other study ID # |
242/10A |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
November 2010 |
| Est. completion date |
April 2011 |
Study information
| Verified date |
November 2010 |
| Source |
University Hospital Freiburg |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
The purpose of this study is to investigate the incidence of acetylsalicylic acid resistance
(ASA-R) among patients under chronic acetylsalicylic acid(ASA) treatment seen at our
outpatient clinic.
Description:
Acetylsalicylic acid (ASA) resistance (R) is best defined as an ineffective inhibition of the
platelet cyclooxygenase (COX)-1 pathway, and has been reported in 1 to 61 % of patients
treated with ASA. Impaired response to ASA has been associated with an increased risk of
ischemic events in patients with known coronary artery disease. We sought to investigate the
incidence of ASA-R in clinical practice.
All consecutive patients under chronic ASA treatment (100mg/d) seen at our outpatient clinic
were systematically included in the registry. All patients were on acetylsalicylic acid for
CAD for at least 1 month. Patients were informed of ASA testing at start of consultation in
the outpatient clinic. Eligible patients provided written informed consent. Peripheral venous
blood samples were analyzed using the whole blood impedance platelet aggregometry Multiplate
analyzer. The Multiplate analyzer device allows to measure platelet aggregation by the
attachment of platelets to two silver coated copper electrodes leading to a rise of
electrical resistance in the sample. The measurements are expressed as arbitrary aggregation
units (AU) and the manufacturers defined cutoffs were used: normal values were 76-136 AU,
partial antiaggregation was defined as ASA values between 31 and 75 AU and complete
antiaggregation was defined as ASA values < 31 AU.