Antiplatelet and Anticoagulant Use in Randomised Trials of Patients Undergoing Endovascular Intervention for Peripheral Arterial Disease: Systematic Review and Narrative Synthesis.

Objective: Randomised trials of new devices for peripheral arterial endovascular intervention are published regularly. The evidence for which antiplatelet and/or anticoagulant (antithrombotic) therapy to use after an intervention is lacking. The aim of this systematic review was to examine the antithrombotic regimens in randomised trials for peripheral arterial endovascular intervention to understand choices made and trends with time or type of device.

Methods: Data sources were the Medline, Embase, and Cochrane Library databases. Randomised trials including participants with peripheral arterial disease undergoing any endovascular arterial intervention were included. Trial methods were assessed to determine whether an antithrombotic protocol had been specified, its completeness, and the agent(s) prescribed. Antithrombotic therapy protocols were classed as peri-procedural (preceding and during intervention), immediate post-procedural (up to 30 days following intervention), and maintenance post-procedural (therapy continuing beyond 30 days).

Results: Ninety-four trials were included in narrative synthesis. Study quality was low. None of the trials justified their antithrombotic therapy protocol. Only 29% of trials had complete peri-procedural antithrombotic protocols, and 34% had complete post-procedural protocols. In total, 64 different peri-procedural protocols, and 51 separate post-procedural protocols were specified. Antiplatelet monotherapy and unfractionated heparin were the most common regimen choices in the peri-procedural setting, and dual antiplatelet therapy (55%) was most commonly utilised post procedure. Over time there has been an increasing tendency to use dual therapy (p < .001). This corresponds with the introduction of newer technologies and trials focussed on below knee intervention.

Conclusion: Randomised trials comparing different types of peripheral endovascular arterial intervention have a high level of heterogeneity in their antithrombotic regimens. Antiplatelet therapy needs to be standardised in trials comparing endovascular technologies to reduce potential confounding. To do this, an independent randomised trial specifically examining antiplatelet therapy following peripheral arterial endovascular intervention is needed.