59 DAPT: are we getting the balance right?

Abstract

Introduction Dual Anti-Platelet Therapy (DAPT) is indicated in Acute Coronary Syndrome (ACS) management and following elective Percutaneous Coronary Intervention (PCI). Optimal duration to balance the risks of bleeding and ischaemic events, including stent thrombosis, is an evolving debate with the advent of newer-generation Drug-Eluting Stents (DES) and evidence from the most recent randomised controlled trials. It should also be tailored to indication and individual patient risk profile. Guidelines concerning DAPT were published by the European Society of Cardiology in 2017 with risk stratification tools to estimate individual bleeding and ischaemic risk to guide and inform these decisions. Our aim was to establish current practice of DAPT prescribing in our department and investigate for adherence to guidelines. Methods Data were collated for 54 prospectively and randomly chosen patients attending general cardiology clinic between February and April 2020 who had commenced DAPT between 12 and 60 months previously following ACS or elective PCI. Patients given DAPT for other indications, or prior to elective angiography where DAPT did not continue thereafter, were not included. Four patients were excluded as insufficient data were available. ‘PRECISE DAPT Score’ at initiation and ‘DAPT score’ 12 months post initiation were retrospectively calculated. Demographic and clinical data were sourced from chart review and electronic laboratory and radiology systems. Data were expressed as mean ± SD and%. Results Fifty patients were included of whom 39 were male and median age was 60.5 years (range 35–90). Of this cohort, 64% were current or ex-smokers, 14% had diabetes, 58% had hypertension, 56% had documented family history of ischaemic heart disease and 46% had hyperlipidaemia. PRECISE DAPT score calculated bleed risk was very low in 24%, low in 42%, moderate in 20% and high in 14%. Mean risk of TIMI major or minor grade bleeding during 12 months DAPT was 1.21% using this score. DAPT score at 12 months following initiation was low in 44% and high in 56%. DAPT Indication was ACS in 62%, elective PCI in 36% and 1 patient underwent 12 months DAPT inappropriately after elective angiography without PCI. Overall, 86% received DESs, 4% drug-eluting balloons and 10% medical therapy. Almost half (48%) did not receive the DAPT duration specified by the cardiologist or based on ESC guidelines where duration was not documented. DAPT was excessive in 40% and insufficient in 8%. Planned DAPT duration was documented at time of angiography or prior to discharge in 80%. Where documented, 12 months DAPT was advised for 92.5% overall and 93.3% following elective PCI. Proton-Pump Inhibitors were not prescribed in 44%. Within 12 months of commencing DAPT, 46 of 50 patients (92%) were reviewed in outpatient clinic. At clinic, planned date of DAPT discontinuation was documented for 35 patients (70%). Among patients who received excessive DAPT, one patient required hospital admission with a TIMI grade minor bleed, 1 patient had a TIMI grade minimal bleed and 1 patient’s urgent prostate biopsy was unnecessarily delayed. Conclusions/Implications Our results indicate that current DAPT prescribing procedures in our department are ineffective and not adhering to guidelines. This could put patients at unnecessary risk of bleeding and ischaemic events. A standardised protocol-based approach to DAPT may improve this practice and reduce risk for our patients.