Low Dose Ticagrelor Versus Low Dose Prasugrel in Patients With Prior Myocardial Infarction

Inclusion Criteria: 1. Provision of informed consent prior to any study specific procedures 2. Post-menopausal female (defined as absence of any vaginal bleeding for a year) or male aged \>50 years 3. A spontaneous MI (ST or Non ST segment elevation) 1 to 3 years before enrolment. In addition, at least one of the following high-risk features: age of 65 years or older, diabetes mellitus requiring medication, a second prior spontaneous MI, multivessel coronary artery disease, or non-end stage renal disease (estimated creatinine clearance of \<60 ml per minute). Exclusion Criteria: 1. Planned use of a P2Y12 receptor antagonist, dipyridamole, cilostazol, or anticoagulant therapy during the study period; 2. Known allergy, intolerance, hypersensitivity to ticagrelor or prasugrel or any excipients, 3. Active pathological bleeding, severe hepatic impairment, a bleeding disorder or a history of an ischemic stroke or intracranial bleeding, a central nervous system tumor, or an intracranial vascular abnormality; 4. Gastrointestinal bleeding within the previous 6 months or major surgery within the previous 30 days; 5. Concomitant use of potent Cytochrome P450 3A4 (CYP3A4) inhibitors (atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin and voriconazole, grapefruit juice over 1 litre daily), CYP3A substrates with narrow therapeutic indices (cyclosporine, quinidine), or inducers (carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampin, and rifapentine). 6. Increased risk of bradycardic events (e.g. known sick sinus syndrome or third degree AV block or previous documented syncope suspected to be due to bradycardia unless treated with a pacemaker). 7. Inability to adhere to the follow-up requirements or any other reason or condition that the investigator feels would place the patient at increased risk if the investigational therapy is initiated.