Introduction Approximately 20% of patients suffer from major adverse cardiovascular events (MACE), within 5 years of stopping dual antiplatelet therapy (DAPT), following an acute coronary syndrome (ACS) event. As such, prolonged DAPT, with aspirin and ticagrelor, has shown significant reductions in MACE, offset by an increased risk of major bleeding. The DAPT score offers a means to predict those who would derive benefit from prolonged therapy. We sought to evaluate applicability of the DAPT score to our population in a tertiary heart attack unit.

Method

Anonymised data was reviewed as part of a larger quality improvement initiative associated with management of ACS. ACS was defined according to standard international criteria. DAPT scores were calculated and compared against our cohort of patients who would have met criteria for prolonged DAPT as per PEGASUS. Patients were excluded if they were at high risk of bleeding, as assessed using CRUSADE scores ≥ 41, or required anticoagulation.

Results Between September to December 2019, 304 patients presented with ACS, of which 89 patients were excluded due to high bleeding risk (56) and concomitant anticoagulation (33). 38 patients were excluded as there was insufficient data to calculate DAPT scores. Of the remaining 177 patients, 55% met PEGASUS criteria for prolonged DAPT, largely driven by multivessel disease (66%). When undertaking the DAPT score, this suggested benefit from prolonged DAPT in 53% of patients meeting PEGASUS criteria.

Conclusion Applying the DAPT score identified just upward of 50% of patients that may benefit from prolonged DAPT. Patients over the age of 65 is a key inclusion criterion in PEGASUS that derived benefit from prolonged therapy; however, is also a risk factor for major bleeding and as such, a negative predictor factor in the DAPT score. This may contribute to the 50% of patients who met criteria for prolonged DAPT as per PEGASUS but would not warrant prolonged DAPT when applying the DAPT score. This review suggests that risk stratification through use of a suitable risk tool (DAPT score) may help to widen the risk benefit of prolonged DAPT by excluding those likely to bleed while ensuring patients at highest ischemic risk are appropriately targeted.

Conflict of Interest None