O-090 - ANTITHROMBOTIC THERAPY FOR AORTIC AND PERIPHERAL ARTERY ANEURYSMS: A SYSTEMATIC REVIEW AND META-ANALYSIS

TOPIC:
Medical therapies (antithrombotic, anti-hypertensive, diabetes mellitus etc.)
AUTHORS:
Wong K.H.F. (University of Bristol ~ Bristol ~ United Kingdom) , Zlatanovic P. (Clinical Center of Serbia ~ Belgrade ~ Serbia) , Bosanquet D. (Aneurin Bevan NHS University Health Board ~ Newport ~ United Kingdom) , Saratzis A. (University of Leicester ~ Leicester ~ United Kingdom) , Kakkos S. (Department of Vascular Surgery, University of Patras Medical School ~ Patras ~ Greece) , Aboyans V. (Dupuytren University Hospital ~ Limoges ~ France) , Twine C. (University of Bristol ~ Bristol ~ United Kingdom)
Introduction:
The role of antithrombotic therapy in aneurysm progression and outcomes following surgical or endovascular intervention is unclear. This review aimed to assess the impact of antithrombotic agents on clinical outcomes in extracranial aneurysms under surveillance or undergoing intervention.
Methods:
A systematic review and meta-analysis was performed. Medline, Embase, and CENTRAL databases were searched. Randomised-controlled trials and observational studies investigating the effect of antithrombotic therapy on clinical outcomes for patients with aortic or extracranial peripheral arterial aneurysms were included. Aneurysm growth rate, major adverse cardiovascular or limb events, mortality, endoleaks, re-intervention rates, and other outcomes were captured.
Results:
Fifty-seven studies involving 121,451 patients were included (26 antiplatelet agents, 12 anticoagulants, 16 any antithrombotic agent(s), 2 intra-operative heparin). Aspirin reduced growth rate of aortic aneurysms under surveillance (mean difference -0.9mm/y, 95%CI -1.74 to -0.07, p=0.03; GRADE certainty: moderate), but not antiplatelets in general (mean difference -0.17mm/y, 95%CI -0.52 to 0.18, p=0.34; GRADE certainty: very low). For aortic aneurysms undergoing intervention, antithrombotics increased 30-day mortality (odds ratio [OR] 2.30, 95%CI 1.51 to 3.51, p<0.001; GRADE certainty: moderate); which remained significant for antiplatelet subgroup analysis (OR 2.33, 95%CI 1.52 to 2.49, p<0.001; GRADE certainty: high). Antiplatelets reduced long-term all-cause mortality (hazard ratio [HR] 0.84, 95%CI 0.76 to 0.92, p<0.001; GRADE certainty: moderate), whilst anticoagulants increased this risk (HR 1.64, 95%CI 1.14 to 2.37, p=0.008; GRADE certainty: very low). Anticoagulants were associated with early and late endoleaks under 3 years, as well as re-intervention rates (p<0.05 for all). Antithrombotic agents did not significantly affect rupture rates in aortic aneurysms under surveillance or after endovascular intervention. Meta-analysis was not possible for studies including ruptured aneurysms and popliteal aneurysms.
Conclusion:
There is a lack of high-quality data for antithrombotic therapy for aneurysms. There is moderate quality evidence from observational data that aspirin reduces AAA growth rates, although no effect was seen for antiplatelets in general when randomised data were included. Antiplatelets reduced post-intervention all-cause mortality for AAA whilst anticoagulants increased the risk of all-cause mortality, endoleak and reintervention. Large, well-designed trials are still required to determine therapeutic benefits of antithrombotic agents for patients with aneurysms.