Risk definition and outcomes with the application of the PEGASUS-TIMI 54 trial inclusion criteria to a "real world" STEMI population: results from the Italian "CARDIO-STEMI SANREMO" registry

BACKGROUND

The PEGASUS-TIMI 54 trial inclusion criteria effectively identified high-risk patients with recent myocardial infarction (MI) who would benefit from continuing dual antiplatelet therapy (DAPT) with ticagrelor for more than 12 months. It is unknown how many real-world patients meet these criteria during the acute phase of ST-elevation MI (STEMI), or the extent to which these criteria predict a patient's risk and prognosis. Study objectives were: (1) determine the proportion of PEGASUS-TIMI 54-like patients (PG-l) in a real-world cohort of patients hospitalized with STEMI and to assess their ischemic and hemorrhagic risk; (2) examine their ischemic and hemorrhagic in-hospital events (major adverse cardiovascular and cerebrovascular events [MACCE] and clinically relevant bleeding); (3) evaluate their long-term outcomes and the impact on the long-term prognosis of the type of DAPT prescribed at discharge.

METHODS

This observational study was conducted in 1086 patients admitted to hospital with a diagnosis of STEMI between February 2011 and March 2018 and enrolled in the CARDIO-STEMI Sanremo registry. Patients' demographic and clinical characteristics, procedural variables, and individual ischemic and hemorrhagic risk scores were assessed in-hospital. Four-year survival was also analyzed.

RESULTS

The proportion of PG-I patients was 69.2%. Compared with non-PG-l patients, PG-l patients were older, had more multivessel disease and comorbidities, and experienced more frequent MACCE (8.3% vs. 3.6%, p = 0.005) and clinically significant bleeding events (6.7% vs. 2.7%, p = 0.008), a higher rate of in-hospital death (6.5% vs. 1.5%, p < 0.001), and higher follow-up mortality rate (14.8% vs. 7.7%; p = 0.002). Four-year survival was significantly lower in the PG-l group (83.9% vs. 91.8%; Log-rank = 0.001) and was related to the cumulative number of concurrent risk factors. In the unadjusted analysis, survival was greater in patients discharged on ticagrelor than on another P2Y12 inhibitor (90.2% vs. 76.7%, Log-rank = 0.001), and the difference was particularly evident in PG-l patients.

CONCLUSIONS

The risk of MACCE for PG-l patients increased with the number of concurrent PEGASUS-TIMI 54 risk features. Treatment with ticagrelor on discharge was associated with improved survival rates during 4 years of follow-up.

Real-World Dual Antiplatelet Therapy Following Polymer-Free Sirolimus-Eluting Stent Implantations to Treat Coronary Artery Disease

Objectives

The objective of this post hoc analysis was to analyze real-world dual antiplatelet therapy (DAPT) regimens following polymer-free sirolimus-eluting stent (PF-SES) implantations in an unselected patient population.

Methods

Patient-level data from two all-comers observational studies (ClinicalTrials.gov Identifiers: NCT02629575 and NCT02905214) were pooled and analyzed in terms of their primary endpoint. During the data verification process, we observed substantial deviations from DAPT guideline recommendations. To illuminate this gap between clinical practice and guideline recommendations, we conducted a post hoc analysis of DAPT regimens and clinical event rates for which we defined the net adverse event rate (NACE) consisting of target lesion revascularization (TLR, primary endpoint of all-comers observational studies) all-cause death, myocardial infarction (MI), stent thrombosis (ST), and bleeding events. A logistic regression was utilized to determine predictors why ticagrelor was used in stable coronary artery disease (CAD) patients instead of the guideline-recommended clopidogrel.

Results

For stable CAD, the composite endpoint of clinical, bleeding, and stent thrombosis, i.e., NACE, between the clopidogrel and ticagrelor treatment groups was not different (5.4% vs. 5.1%, p = 0.745). Likewise, in the acute coronary syndrome (ACS) cohort, the NACE rates were not different between both DAPT strategies (9.2% vs. 9.3%, p = 0.927). There were also no differences in the accumulated rates for TLR, myocardial infarction ([MI], mortality, bleeding events, and stent thrombosis in elective and ACS patients. The main predictors for ticagrelor use in stable CAD patients were age < 65 years, smaller vessels, treatment of ostial and calcified lesions, and in-stent restenosis.

Conclusion

Within the framework of a post hoc analysis based on a real-world, large cohort study, there were no differences in the combined endpoint of major adverse cardiac events (MACE), bleeding and thrombotic events for clopidogrel and ticagrelor in stable CAD or ACS patients. Despite the recommendation for clopidogrel by the European Society of Cardiology (ESC), real-world ticagrelor use was observed in subgroups of stable CAD patients that ought to be explored in future trials.

Pharmacodynamic Effects of Vorapaxar in Prior Myocardial Infarction Patients Treated With Potent Oral P2Y12 Receptor Inhibitors With and Without Aspirin: Results of the VORA-PRATIC Study

Background Vorapaxar as an adjunct to dual antiplatelet therapy (DAPT) reduces thrombotic events in patients with prior myocardial infarction at the expense of increased bleeding. Withdrawal of aspirin has emerged as a bleeding reduction strategy. The pharmacodynamic effects of vorapaxar with potent P2Y12 inhibitors as well as the impact of dropping aspirin is unexplored and represented the aim of the VORA-PRATIC (Vorapaxar Therapy in Patients With Prior Myocardial Infarction Treated With Newer Generation P2Y12 Receptor Inhibitors Prasugrel and Ticagrelor) study. Methods and Results Post-myocardial infarction patients (n=130) on standard DAPT (aspirin+prasugrel or ticagrelor) were randomized to 1 of 3 arms: (1) triple therapy: aspirin+prasugrel/ticagrelor+vorapaxar; (2) dual therapy (drop aspirin): prasugrel/ticagrelor+vorapaxar; (3) DAPT: aspirin+prasugrel/ticagrelor. Pharmacodynamic assessments were performed at 3 time points (baseline and 7 and 30 days). Vorapaxar reduced CAT (collagen-ADP-TRAP)-induced platelet aggregation, a marker of platelet-mediated global thrombogenicity (triple therapy versus DAPT at 30 days: mean difference=-27; 95% CI,-35 to -19; P<0.001; primary end point). This effect was attenuated but still significant in the absence of aspirin (dual therapy versus DAPT at 30 days: mean difference=-15; 95% CI,-23 to -7; P<0.001; between-group comparisons, P<0.05). Vorapaxar abolished TRAP-induced aggregation (P<0.001), without affecting thrombin generation and clot strength. There were no differences in markers of P2Y12 reactivity. Markers sensitive to aspirin-induced effects increased (P<0.001) in the dual-therapy arm. Conclusions In post-myocardial infarction patients treated with potent P2Y12 inhibitors, vorapaxar reduces platelet-driven global thrombogenicity, an effect that persisted, albeit attenuated, in the absence of aspirin and without affecting markers of P2Y12 reactivity or clot kinetics. The clinical implications of these PD observations warrant future investigation. Registration URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT02545933.