Stroke thromboemboli are often described as white (platelet-rich) or red (red blood cell (RBC)-rich) when having an atherosclerotic or cardiac origin respectively. Secondary stroke prevention is mainly based on antiplatelet therapy for atherosclerotic etiologies and anticoagulation for cardioembolic etiologies. Yet, up to 25% of patients still experience a recurrent stroke. Better understanding of thromboembolus composition can improve our understanding of underlying pathophysiologies and potentially improve prevention strategies. The aim was to perform a large-sample multi-parameter quantitative histological analysis to investigate differences in thromboembolus composition of different etiologies.
Thromboemboli (n=501) were collected from thrombectomy-treated ischemic stroke patients at Groeninge Hospital (Kortrijk, Belgium) and CHU Lille (Lille, France). Stroke etiology was categorized according to the TOAST classification. Histological analysis was performed for the amount RBCs, platelets, fibrin, von Willebrand factor (VWF), leukocytes, citrullinated histone H3 (H3Cit) and extracellular (ex)DNA.
Compared to large-artery atherosclerotic (LAA) thromboemboli (Fig.1), cardioembolic (CE) thromboemboli contained significantly less RBCs and significantly more platelets, fibrin, leukocytes and exDNA. VWF and H3Cit content were similar in CE/LAA thromboemboli. Cryptogenic thromboemboli contained relatively low amounts of RBCs and high amounts of platelets (Fig.1), similar to CE thromboemboli. Notwithstanding these population differences, a typical CE or LAA thromboembolus cannot be defined given the heterogeneity in RBC/platelets.
In contrast to current concepts of ‘white’ atherosclerotic and ‘red’ cardiac thrombi, CE thromboemboli are more platelet-rich compared to RBC-rich LAA thromboemboli, with a heterogenous RBC/platelet thrombus profile. Such data could hint at combining antiplatelet with anticoagulation therapy in stroke prevention, as shown in the COMPASS-trial.
Not applicable