DAPT Strategy in HBR Patients Undergoing Complex PCI Following ACS: Second-Phase Beta Testing of a Patients Decision Aid

Among patients with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI) and stent implantation, 17.5% are both at high bleeding risk (HBR) and have undergone complex PCI, which also places them at high thrombotic risk. In this population, several dual antiplatelet therapy (DAPT) strategies may be considered: (1) de-escalation of DAPT intensity after 1 to 3 months (switch from ticagrelor/prasugrel to clopidogrel), (2) shortening DAPT duration to 1 to 3 months followed by antiplatelet monotherapy, (3) 12-month clopidogrel-based DAPT, and (4) 12-month ticagrelor/prasugrel-based DAPT. Selecting the most appropriate DAPT strategy in this dual-risk context is complex, and clinical trial evidence is limited for this specific subgroup. In the absence of clear guideline recommendations to support decision-making for patients facing both elevated bleeding and thrombotic risks, structured shared decision-making support is needed. In this context, within research project 2025-3499 conducted with pharmacy residents, we developed a patient decision aid (PDA) designed to support shared decision-making by helping patients understand their risks, available options, and potential consequences, so they can express their preferences regarding antiplatelet therapy. The PDA aims to facilitate shared decisions by improving patients' understanding of benefits and harms and aligning choices with patient values. A preliminary version of the tool has already undergone alpha testing with a small group of internal users (physicians, pharmacists, and patient partners). The next step is beta testing, that is, real-world testing with the target population and clinicians to evaluate usability and acceptability in routine practice.

Inclusion Criteria (Patients) * Adults aged 18 years or older * Hospitalized on the coronary care unit ward at the Montreal Heart Institute (MHI) * Acute coronary syndrome (ACS) during the current episode of care, treated with PCI and placement of one or more coronary stents * High bleeding risk based on PRECISE-HBR score and high thrombotic risk, with both risks considered of comparable clinical importance by the treating medical team Inclusion Criteria (Clinicians) \- Clinicians working in the MHI coronary care unit (cardiologists, medical residents, nurse practitioners, or pharmacists) who use the patient decision aid with one or more study participants Exclusion Criteria (Patients) * Receiving therapeutic anticoagulation * Planned cardiac surgery during the same episode of care * Prior history of coronary stent thrombosis * Antiphospholipid syndrome or known thrombophilia * Unable to participate in shared decision-making * Unable to understand spoken and written French or English * Concurrent participation in another study (followed within another research protocol) * Transferred from another center for reasons other than coronary angiography at MHI and expected to return to the referring center for ongoing care (i.e., "fly-in/fly-out" patients)