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Duration of Platelet Inhibition by Aspirin

This study has been completed.
Information provided by:
Hopital du Sacre-Coeur de Montreal Identifier:
First received: April 30, 2008
Last updated: August 20, 2012
Last verified: March 2009

The well established importance of regular aspirin administration stands on firm grounds, as large meta-analyses have shown this therapy to significantly reduce the risk of death. However, not all patients benefit of aspirin administration to the same extent, thus high-lighting a sub-population of patients with inadequate platelet response to ASA. The mechanisms underlying reduced ASA efficacy remain elusive. A recent report has suggested that platelets, long believed to be incapable of de novo protein synthesis, may retain their ability to form the cyclooxygenase enzyme, once it has been inactivated by aspirin. This may explain the inefficacy of the drug to induce sustained platelet inhibition in certain patients.

The current study aims to evaluate, in patients suffering from stable coronary artery disease, the stability of platelet inhibition by aspirin during the normal once daily dosing regimen.

Condition Intervention
Coronary Artery Disease
Other: Platelet aggregation

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Evaluation of Duration of Platelet Inhibition by Aspirin in a Standard 24-hour Interval Dosing Regimen

Resource links provided by NLM:

Further study details as provided by Hopital du Sacre-Coeur de Montreal:

Primary Outcome Measures:
  • Platelet aggregation TxA2 formation

Enrollment: 10
Study Start Date: July 2008
Study Completion Date: January 2009
Primary Completion Date: January 2009 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Patients suffering from stable CAD, on chronic ASA therapy
Other: Platelet aggregation
Platelet aggregation TxA2 formation


Ages Eligible for Study:   18 Years to 90 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Patients suffering from stable CAD, on chronic ASA therapy

Inclusion Criteria:

  • Patients suffering from stable CAD, on chronic ASA therapy
  • Patients willing to participate in the study and to sign the informed consent form

Exclusion Criteria:

  • Acute coronary syndrome or revascularization in the last 3 months prior to enrolment
  • Concurrent ingestion of nonsteroidal anti-inflammatory drugs (NSAIDs, including COX-2 selective anti-inflammatory drugs), clopidogrel, ticlopidine, dipyridamole, warfarin or acenocoumarol
  • Frequent use (more than once a week) of non-prescription NSAIDs or drugs containing ASA in the 10 days preceding enrolment
  • Major surgical procedure within 1 month before enrolment
  • Hemorrhagic diathesis or known platelet dysfunction
  • Platelet count outside the 100 to 450 x109/L range for technical reasons
  • Hematocrit < 25% or haemoglobin < 100 g/L
  • Patient undergoing dialysis for chronic renal failure
  • Patient found to be ASA resistant
  Contacts and Locations
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Please refer to this study by its identifier: NCT00671021

Canada, Quebec
Hôpital du Sacré-Coeur de Montréal
Montreal, Quebec, Canada, H4J 1C5
Sponsors and Collaborators
Hopital du Sacre-Coeur de Montreal
Principal Investigator: Jean G Diodati, MD Hopital du Sacre-Coeur de Montreal
  More Information Identifier: NCT00671021     History of Changes
Other Study ID Numbers: C.E. 2007-05-42
Study First Received: April 30, 2008
Last Updated: August 20, 2012

Keywords provided by Hopital du Sacre-Coeur de Montreal:
platelet aggregation

Additional relevant MeSH terms:
Coronary Artery Disease
Myocardial Ischemia
Coronary Disease
Heart Diseases
Cardiovascular Diseases
Arterial Occlusive Diseases
Vascular Diseases
Anti-Inflammatory Agents, Non-Steroidal
Analgesics, Non-Narcotic
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Inflammatory Agents
Antirheumatic Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Cyclooxygenase Inhibitors
Enzyme Inhibitors
Antipyretics processed this record on March 27, 2017