Cohort study using data from Clinical Practice Research Datalink (CPRD). The study cohort includes all patients who received at least one prescription for ticagrelor for the first time between December 2010 and March 2015, following ACS. Patient baseline characteristics will be described: (Age, Gender, Body Mass Index, Smoking status, Sociodemographic status), type of ACS and interventions, CV history and comorbidities, bleeding and respiratory history.

The following outcomes will be examined: Incidence of vascular events (composite MI, Stroke, vascular death, specific vascular event and all cause death), incidence of bleeding and incidence of dysponea. Time to event for vascular events, bleeding and dyspnoea.

Inclusion Criteria:

• First prescription (index date) for ticagrelor between Dec 2010 and Mar 2015
• At least 12 months history in database prior to first ticagrelor prescription
• Linkage to Hospital Episode Statistics (HES)
• Acute Coronary Syndrome (ACS) event in the three months prior to and including the index date

Exclusion Criteria:

Primary care prescription for clopidogrel or prasugrel between the ACS date and the index date

Patients prescribed ticagrelor in primary care, following Acute Cornoary Syndrome (ACS), for the first time (Dec 2010 - Mar 2015) in Cliniical Practice Research Datalink primary care data and followed for up to 12 months.