Association Between Perioperative Platelet Function and Major Adverse Perioperative Events

The Association Between Perioperative Platelet Inhibition (Function) and Major Adverse Perioperative Cardiac Events in Post Percutaneous Coronary Intervention Patients Undergoing Non-cardiac Surgery

This study will examine the degree of blood thinning (platelet function) in patients coming for non-cardiac surgery on antiplatelet agents using platelet function tests called thromboelastography (TEG) and platelet mapping assay (PMA) and major cardiac complications that occur any time after surgery (perioperative).

Patients who have had stents in their coronary arteries (PCI) have to stay on antiplatelet agents to prevent clotting of their stents. These patients often require non-cardiac surgery (NCS) at some stage after their PCI. The rate of major cardiac complications (MACE)in this population is very high and it is unclear why they are at higher risk than the general population. It is possible their antiplatelet is not adequate, or that surgery causes them to be more clot prone. This is a prospective, multicentre observational study.

Inclusion Criteria:

• patients between ages 30-85 years old, receiving post-PCI aspirin and/or clopidogrel therapy
• patients undergoing non-ambulatory, NCS
• patients will have received a bare metal coronary stent within the last 12 months or a drug eluting stent at any time prior to their NCS
• the type of surgery has to be such that there are no contra-indictions to remain on an anti-platelet agent
• surgeon must agree to keep the patient on at least one anti-platelet agent during the perioperative period

Exclusion Criteria:

• clotting abnormalities
• drugs affecting platelet function other than aspirin or clopidogrel
• moderate renal impairment
• liver dysfunction with co-existing thrombocytopenia