Management of carotid free-floating thrombus: A systematic review

A free-floating thrombus in the carotid artery (cFFT) is a high-risk vascular condition for stroke. Treatment recommendations are lacking. This systematic review aimed to identify the safety and effectiveness of existing management strategies for cFFT.

PubMed and Embase were systematically searched from inception to May 2025, using search terms including "free-floating thrombus" and "carotid," and treatment strategies. Eligible studies reported on treatment and clinical outcomes. Two authors independently screened eligible literature and extracted data. Study quality was assessed with the Methodological Index for Non-Randomized Studies score (MINORS score). Primary end points were the composite of any nonfatal stroke and all-cause death (death/stroke) at the short-term (<30 days) and long-term (>30 days) follow-up after initial treatment.

Our literature search revealed 11 studies, encompassing 179 patients with cFFT. These studies were predominantly of low quality, with a mean MINORS score of 9 for noncomparative studies and 15 for comparative studies; notably, no randomized controlled studies were identified. Twenty treatment strategies were identified, grouped as antithrombotic medication (AM; n = 120/179 [67.0%]), or AM combined with endovascular treatment (EVT) (n = 20/179 [11.2%]), carotid endarterectomy (CEA) (n = 38/179 [21.2%]), and combined EVT + CEA (n = 1/179 [0.6%]). Sequential treatments were analyzed by timing: those initiated before 30 days contributed to short-term outcomes and those thereafter to long-term outcomes. Short-term combined death/stroke rates were reportedly highest with AM alone (n = 8/120 [6.7%]), followed by EVT (n = 1/20 [5.0%]) and CEA (n = 1/38 [2.6%]). The AM group reported a short-term all-cause death rate of 5.0% (n = 6/120) and nonfatal stroke rate of 1.7% (n = 2/120). Long-term outcomes occurred solely in the AM group, yielding a death/stroke rate of 6.5% (n = 3/46), comprising two deaths (n = 2/46, 4.3%) and one stroke (n = 1/46, 2.2%).

The published literature on cFFT is limited and lacks high-quality studies. This review suggests that all currently reported treatment strategies are associated with a considerable risk for stroke or death. Anticoagulation alone appears to be inadequate, thereby challenging current European Society for Vascular Surgery guideline recommendations, whereas the results for CEA suggest it may represent a more favorable option in patients amenable to surgery. These findings should be interpreted with caution given the small number of patients included. Nevertheless, our data may help to inform the design of future studies and contribute to the development of more standardized treatment strategies.