Multiple Daily Doses Of Aspirin To Overcome Aspirin Hyporesponsiveness Post Cardiac Bypass Surgery

NCT01618006 | Completed Phase 2

• 1 other identifier: NIF-11271
• Study Type: interventional
• Target: 120
• 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 than giving aspirin once daily at blocking platelet activity.

Conditions

Postoperative; Dysfunction Following Cardiac Surgery

Outcome Measures

Primary Outcomes (1)

• Serum Thromboxane: Define an inadequate aspirin response as a value >0.69 ng/ml, which is 2 SD above the mean of aspirin-treated patients

  Postoperative Day 4

Secondary Outcomes (3)

• 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

• Arachidonic Acid Induced Multiple Electrode Platelet Aggregometry (MEA):Aggregation was recorded for 6 minutes and will be reported as the area under the curve (aggregation units x min).

  Postoperative Day 4

• DNA genetic analyses for single nucleotide polymorphisms

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

Study Arms (3)

Aspirin 81mg daily

ACTIVE COMPARATOR

Patients will receive 81mg daily during the postoperative period.

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 four times daily

EXPERIMENTAL

Patients will receive ASA 81mg four times daily until postoperative day 7 or 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 81mg 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

You may not qualify if:

• (a) initial platelet count \<100,000 (b) significant liver disease (c) renal impairment (CrCl\<30 ml/min/1.73 m2) (d) receiving (or planned) clopidogrel therapy (e) receiving NSAIDs or other drugs that might interfere with aspirin's platelet-inhibitory effect (f) need for therapeutic doses of parenteral or oral anticoagulants after surgery and (g) off-pump CABG (h) clinically important bleeding (chest tube drainage \>200ml/hr for 6hrs)

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

  STUDY CHAIR

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: June 1, 2012
• First Posted: June 13, 2012
• Study Start: January 1, 2012
• Primary Completion: April 1, 2013
• Study Completion: August 1, 2013
• Last Updated: March 19, 2015

Record last verified: 2015-03

Locations

CA (1)