P6410Eligibility and preference of extended antithrombotic therapy for secondary prevention after an acute coronary syndrome

Abstract

Abstract Background and purpose Recent randomized controlled trials (RCTs) have evaluated the benefit of extended antithrombotic therapy in secondary prevention of Acute Coronary Syndromes (ACS). However, the numerous and strict enrollment criteria may limit the validity and reproducibility of the published results in clinical practice. We aimed to estimate the eligibility for participation in RCTs of a group of patients followed up for ACS. Methods We applied the enrollment criteria of 2 RCTs (PEGASUS [low-dose ticagrelor – 60mg twice daily] and COMPASS [low-dose rivaroxaban – 2.5mg twice daily) to 780patients with history of ACS. Results A total of 938 patients admitted for ACS during 30months. Mean age was 68.8±10.3 years, 70.4% (n=660) males. Baseline characteristics are summarised in Table 1. Median length of stay was 6.0 (IQR 3.0–11.0 days). In-hospital mortality was 7.9%. Mortality after discharge within 12 months was 9.7%. A total of 780 patients were screened for trial enrollment after 12 months of follow-up. The proportion of patients fulfilling the trial enrollment criteria were 32.1% for PEGASUS and 35.9% for COMPASS. 41.6% of patients were eligible for at least one RCT. The main reasons for ineligibility for RCTs were the presence of comorbidities for PEGASUS and bleeding risk for COMPASS (Figure 1). Patients not fulfilling enrollment criteria for any RCT (58.4%) were older (71.4±9.7 vs 65.2±10.2 years, p<0.0001), more likely to have worse renal function (CrCl 47.8±28.8 vs 73.9±21.2 ml/min/1.73m2, p<0.0001), less left ventricular ejection fraction (44.4±11.4 vs 51.9±7.5%, p<0.0001) and had longer length of stay (7 IQR 4–13 vs 5 IQR 3–8 days, p<0.0001). The main differences in eligible and ineligible patients in both RCTs are summarised in Table 2. Baseline characteristics and differences Conclusions Patients enrolled in RCTs are only partly representative of the real world population with history of ACS, mainly due to the higher prevalence of comorbidities and bleeding risk factors in this population. It is uncertain if these patients still benefit from theses therapies as in the published RCTs.