Multiple Daily Doses of Aspirin to Overcome Hyporesponsiveness Post Cardiac Bypass Surgery (ASACABG)- Part B

NCT01902498 | Completed Phase 2

• 1 other identifier: NIF-13324
• Study Type: interventional
• Target: 70
• Locations: 1 country
• Sites: 1

Brief Summary

Cardiac bypass surgery is an important treatment for patients with severely blocked arteries (tubes that delivery oxygen and nutrients to the heart). Hundreds of thousands of these operations are done each year to help relieve patients' chest pain and to prevent future heart attacks. The surgery is done by "bypassing" blood flow around badly clogged arteries by sewing on healthy vessels from another part of the body (usually from the leg or the chest). Aspirin (a blood thinner) is given to patients once a day after their surgery because it stops "sticky" cells in the blood (platelets) from blocking these new vessels (which may lead to a future heart attack). Research has shown that aspirin does not work as well in people after they have bypass surgery as the investigators might expect (for reasons that are not fully understood). One reason aspirin may not work as well after surgery is because the body makes many more platelets after surgery than it would under normal circumstances. All of these new platelets overwhelm the aspirin and continue to be "sticky" and ready to block off arteries. The investigators believe that giving multiple daily doses of aspirin following bypass surgery is more effective at blocking platelet activity than giving aspirin once daily.

Conditions

Postoperative Dysfunction Following Cardiac Surgery

Keywords

aspirin

Outcome Measures

Primary Outcomes (1)

• Serum Thromboxane Concentration (ng/ml)

  Postoperative Day 4

Secondary Outcomes (2)

• Arachidonic Acid Induced Light Transmission Aggregometry (LTA): Aggregation will be expressed as the maximum percent change in light transmittance from baseline, with platelet-poor plasma used as a reference.

  Postoperative Day 4

• DNA genetic analyses for single nucleotide polymorphisms

  A single preoperative blood sample was drawn (on average 1 day prior to surgery)

Study Arms (3)

Aspirin 162mg twice daily

EXPERIMENTAL

Patients will receive 162mg twice daily during the postoperative period, until day 7 postop or the end of hospitalization.

Drug: Aspirin

Aspirin 325mg daily

ACTIVE COMPARATOR

Patients will receive 325mg daily during the postoperative period, until day 7 postop or the end of hospitalization.

Drug: Aspirin

Aspirin 81mg daily

ACTIVE COMPARATOR

Patients will receive 81mg daily during the postoperative period, until day 7 postop or the end of hospitalization.

Drug: Aspirin

Interventions

Aspirin DRUG

Aspirin 81mg po daily x 7days or end of hospitalization. First dose administered on post op day 1.

Aspirin 162mg twice daily

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult subjects who undergo elective or urgent CABG surgery who are on or off aspirin during the preoperative period with or without valve replacement

You may not qualify if:

• initial platelet count \<100,000
• receiving NSAIDs or other drugs that might interfere with aspirin's platelet-inhibitory effect
• clinically important bleeding (chest tube drainage \>200ml/hr for 6hrs), or bleeding disorders that preclude the use of randomized therapies
• patients who do not provide informed written consent

Sponsors & Collaborators

• Hamilton Health Sciences Corporation: lead

Study Sites (1)

Hamilton General Hospital

Hamilton, Ontario, L8L2X2, Canada

Location

MeSH Terms

Interventions

Aspirin

Intervention Hierarchy (Ancestors)

Salicylates; Hydroxybenzoates; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals

Study Officials

• Jeremy Paikin, MD

  Cardiology Fellow

  PRINCIPAL INVESTIGATOR

• John Eikelboom, MBBS

  Hematologist, PHRI researcher

  PRINCIPAL INVESTIGATOR

• Richard Whitlock, MD

  Cardiac Surgeon, PHRI researcher

  PRINCIPAL INVESTIGATOR

• Guillaume Pare, MD

  Medical Biochemist, PHRI researcher

  PRINCIPAL INVESTIGATOR

• Jack Hirsh, MD

  Hematologist, Professor Emeritus, PHRI researcher

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: July 15, 2013
• First Posted: July 18, 2013
• Study Start: July 1, 2013
• Primary Completion: March 1, 2014
• Study Completion: July 1, 2014
• Last Updated: March 19, 2015

Record last verified: 2015-03

Locations

CA (1)