Background

Current therapy and management for patients with acute coronary syndrome (ACS) is based on 2020 ESC guideline. Here, recommendations prefer the use of prasugrel over ticagrelor primarily based on results from ISAR-REACT 5 trial. Since clinical limitations of eligibility for prasugrel or ticagrelor in ACS, we sought to evaluate proportions of potential eligibility of current ADP-inhibitors in NSTEMI patients. 

Methods

In this retrospective single center study, we consecutively screened all ACS patients presenting between 1^st of July 2016 and 30^thof June 2018. In this 24-month period, 6789 patients presented to CPU with suspected ACS of whom 1504 we diagnosed ACS. Acute myocardial infarction (MI) was diagnosed in-hospital by treating clinicians based on all clinical information, using the diagnostic criteria of the 3rd or 4^th universal MI definition. We also evaluated major adverse cardiovascular and cerebrovascular events based on electronical medical reports. Statistical analyses were performed using MedCalc Ver. 20.111.

Results

NSTEMI was diagnosed in 675 (45%) of 1502 patients. 90% of patients received a coronary angiography of which 395 (59 %) patients received PCI, and 11% revived CABG. The proportion of patients with coronary angiography but without intervention was 31 % (n = 211). Mean age was 74 (IQR 62-81) years and mean weight 82 kg (IQR 70-95). 10 % (n = 64) had history of transient ischaemic attack or stroke.10.2 % (n = 69) of NSTEMI patients were pre-treated with a P2Y12-inhibitor and 32 % (n = 216) were under oral anticoagulant therapy. Prevalence of ineligible patients for prasugrel totals up to 292 (43.3 %) when history of transient ischaemic attack or stroke, and pre-treatment with P2Y12 inhibitor before index hospitalization, a decision for conservative treatment strategy with or without knowledge of coronary angiography, or the need for (N)OAC were considered. Prevalence of ineligible patients totals up to 448 (66.4 %) with the additional consideration of age ≥ 75 years and body weight < 60 kg. In contrast, the eligibility of ticagrelor in NSTEMI patients was 79.6 % (n = 537) considering label restrictions.

Conclusions

Data on the comparative eligibility for either ticagrelor or prasugrel and plausible reasons for non-administration of either drug are sparse. Eligibility of NSTEMI patients for ADP-inhibitors is considerably lower for prasugrel than for ticagrelor. Rates of non-eligible patients for prasugrel range from 43 % to 66 %, depending on whether variables that require caution such as age ≥ 75 years or body weight < 60 kg are considered, of whom data is limited concerning clinical benefit. Our findings provide interesting insights into the practical consequences of label restrictions of contemporary guideline recommendations on the optimal selection of antiplatelet therapies in confirmed NSTEMI patients.