Guideline versus clinician recommended duration of dual antiplatelet therapy following acute coronary syndrome (ANZACS-QI 78).

Aim: The recommended duration of dual anti-platelet therapy (DAPT) following acute coronary syndrome (ACS) for patients without atrial fibrillation varies from 1 month to 1 year depending on the balance of risks of ischaemia and major bleeding. Patients on DAPT with a high risk of gastrointestinal bleeding are also recommended to receive a proton pump inhibitor (PPI). Our aim was to audit current practice against the 2020 European Society of Cardiology (ESC) guideline recommendations.

Methods: One hundred consecutive ACS patients treated with percutaneous coronary intervention discharged from Middlemore Hospital and without atrial fibrillation in the first quarter of 2023 were studied. ANZACS-QI ischaemic (I) and bleeding (B) risk scores were calculated, with patients categorised in four groups based on ESC recommendations-low I/low B risk, low I/high B, high I/low B and high I/high B. Guideline and clinician recommended duration of DAPT and prescription of PPI were compared.

Results: All patients were planned for DAPT at discharge and 91% a PPI. Up to four out of five ACS patients could have been planned for shorter DAPT durations based on the ESC guideline recommendations. Over half of included patients (53%) had a high bleeding risk, yet 85% of these patients received 12 months of DAPT despite ESC recommendations of 1-3 months.

Conclusions: There was a divergence between clinical practice and the recommendations of the 2020 ESC guidelines. We discuss these results in relation to the updated August 2023 ESC guidelines, which have reaffirmed a 12-month duration of DAPT as the default position.