The Safety of Ticagrelor Monotherapy After Primary Percutaneous Coronary Intervention for ST-elevation Myocardial Infarction and the Effect on Intramyocardial Haemorrhage

Study Overview
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Brief Summary
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The main goal of this clinical trial is to assess the safety of direct omission of aspirin after Percutaneous Coronary Intervention (PCI) in patients with ST elevation myocardial infarction (STEMI). The secondary objectives are to demonstrate the reduction of intramyocardial haemorrhage and infarct size, which will be measured after 1 week; to compare clinical bleeding outcomes and to compare platelet reactivity and inflammatory response in STEMI patients receiving ticagrelor monotherapy versus dual antiplatelet therapy. Patients will be treated with either ticagrelor monotherapy or dual antiplatelet therapy (aspirin plus ticagrelor) after PCI. They will be compared to see if the omission of aspirin is safe in terms of major adverse cardiac and cerebral events at 13 months follow-up.

Official Title
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The Safety of Ticagrelor Monotherapy After Primary Percutaneous Coronary Intervention for ST-elevation Myocardial Infarction and the Effect on Intramyocardial Haemorrhage

Conditions
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ST Elevation Myocardial Infarction

Intervention / Treatment
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* Drug: Ticagrelor
* Drug: Aspirin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical and electrocardiographical diagnosis of STEMI Successful PCI (according to the treating physician) of the infarct-related vessel with a modern DES Exclusion Criteria: Known allergy or contraindication for aspirin, ticagrelor or prasugrel. Previous PCI or MI less than 12 months ago Previous cardiac surgery Participation in another clinical cardiology study or study concerning platelet aggregation/ thrombosis. Pregnancy and breast feeding Concurrent use of oral anticoagulants (OAC) The periprocedural use of GPIIb/IIIa inhibitors Planned surgical intervention within 12 months of PCI Creatinine clearance <30mL/min or dialysis PCI of stent thrombosis Suboptimal stent result as judged by the interventional cardiologist. Contra-indications for MRI or unable to undergo MRI (only applicable for the CMR subgroup population).

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment arm<br>Ticagrelor monotherapy instead of dual antiplatelet therapy (aspirin plus ticagrelor) | Drug: Ticagrelor<br>* Ticagrelor monotherapy for 12 months<br>|
| Active Comparator: Control arm<br>Dual antiplatelet therapy (aspirin plus ticagrelor) for 12 months. | Drug: Ticagrelor<br>* Ticagrelor monotherapy for 12 months<br>Drug: Aspirin<br>* Dual antiplatelet therapy (aspirin plus ticagrelor) for 12 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite of major adverse cardiac and cerebral events (MACCE) | Consisting of: myocardial infarction, stent thrombosis, ischemic stroke, cardiovascular mortality / all-cause mortality | 13 months | 
| Intramyocardial haemorrhage (IMH) | Size of IMH and infarct determined by Cardiac Magnetic Resonance imaging at day 5-8 post-PCI. | day 5-8 post PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bleeding complications | Defined as Bleeding Academic Research Consortium (BARC) 2 or greater | 13 months | 
| All-cause mortality |  | 13 months | 
| Platelet reactivity of aspirin measured as Aspirin Reaction Units (ARU) using the VerifyNow test | Differences in platelet reactivity between ticagrelor monotherapy and ticagrelor + aspirin will be measured | 5-8 days |