According to the World Health Organization (WHO), CVD is the leading cause of death worldwide, accounting for an estimated 17.9 million deaths each year. This represents about 31% of all deaths worldwide.Although substantial progress has been made in the diagnosis and treatment of acute coronary syndromes (ACS), cardiovascular disease remains the leading cause of death worldwide, with nearly half of these deaths due to ischaemic heart disease.Effective secondary prevention after ACS involves prompt recognition of symptoms, early hospitalization, and initiation of appropriate medical therapy. Revascularization, antiplatelet therapy, lipid-lowering therapy, and blood pressure control are all important components of ACS management. Antiplatelet therapy represents the cornerstone treatment and secondary prevention of CAD. Compared with placebo, antiplatelet therapy has been shown to reduce recurrent major adverse cardiovascular events (MACE) among patients with stable CAD or ACS, however, it is inevitably associated with increased bleeding.Patients with ACS undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES) are currently recommended dual antiplatelet therapy (DAPT), consisting of aspirin with P2Y12 receptor inhibitors to prevent thrombotic complications such as stent thrombosis. Patients receive DAPT for 6-12 months after DES implantation. The efficacy and safety of prolonged DAPT have been questioned. Compared to less than 12 months of DAPT, 12 months of DAPT did not reduce the risk of myocardial infarction, stent thrombosis, strokes, or cardiac or all-cause mortality, but increased the risk of major bleeds.DAPT beyond 12 months reduces the risk of myocardial infarction and stent thrombosis, but there is a substantial increase in major bleeding risk and all-cause mortality which need to be addressed. DAPT with aspirin and a P2Y12 inhibitor is recommended following an acute coronary syndrome (ACS) to help prevent further thromboembolic events.There are three commercially available oral P2Y12 inhibitors; clopidogrel, prasugrel, and ticagrelor. Clopidogrel is the most commonly used agent, likely due to its cost-effectiveness compared to the other two agents. However, clinical trials have shown that both prasugrel and ticagrelor are associated with lower rates of CV death, MI, or stroke when compared to clopidogrel in the management of ACS .Safety concerns exist surrounding the appropriate strategy for switching between oral P2Y12 inhibitors. Due to the pharmacological and pharmacokinetic differences between oral P2Y12 inhibitors, including half-life, site of action, mechanism, and onset of action, there may be concern that switching between agents could lead to a period of inadequate platelet inhibition and further thromboembolic events. In contrast, there may be concern that a period of more robust platelet inhibition could occur while switching between agents, raising the risk of potential bleeding.Guidance on the best modality for switching between these agents had been lacking, particularly regarding timing and the need for reloading. This study aims to evaluate the safety and efficacy of different antithrombotic strategies, particularly for switching between oral P2Y12 inhibitors at our institution, and compare our findings to the most recently published expert consensus recommendations.