Evidence for periprocedural antiplatelet therapy, heparinization and bridging of coumarin therapy in carotid revascularization.

Abstract

Thromboembolism prevention is a crucial factor determining both the natural outcome and outcome of intervention of stenotic atherosclerotic carotid artery pathology. Roughly 80% of all natural course cerebral ischemic events are caused by thromboembolism, versus 20% due to hemodynamic insufficiency. The risk of periprocedural cerebral (micro-) thromboembolization during carotid revascularization is considered to be even higher, with a higher rate in carotid artery stenting (CAS) as compared to carotid endarterectomy (CEA). Guidelines on CEA and CAS are unanimous in advising perioperative continuation of antiplatelet therapy (APT) for all patients to prevent thromboembolization without specification of the type of APT. Recommendations on dual antiplatelet (DAPT) therapy are inconsistent. Bridging vitamin K antagonists (VKA) perioperative with unfractionated heparin (UFH) or low-molecular weight heparins (LMWHs) might not be necessary for CAS, while CEA-specific data is lacking. No data are available on the use and position of direct-acting oral anticoagulants (DOACs) for CEA or CAS. Guidelines on treatment of carotid artery disease currently do not provide information on perioperative heparinization. There are several monitoring tools to detect perioperative micro-embolic signals during intervention or new cerebral white matter lesions following CEA or CAS. Transcranial Doppler ultrasonography (TDU) and diffusion weighed imaging (DWI) might be used to assess these (secondary) outcome measurements. The use of platelet function testing (PFT) to tailor APT might contribute to finding the therapeutic place of stronger APT and new APT regimen. Periprocedural antiplatelet and anticoagulation therapy for carotid revascularization still lacks solid evidence and guidelines do not yet cover the full spectrum of anticoagulants and procedural steps. This review aims to cover and discuss the full spectrum of available antiplatelet and anticoagulant drugs and therapies available for thromboembolism prevention during all crucial steps of revascularization and specify the need to know topics to be addressed in future research.