Abstract:Objective To investigate the incidence of calf muscular venous thrombosis (CMVT) and analyze its risk factors among patients with severe acute ischemic stroke (AIS) in the Neurological Intensive Care Unit (NICU). Methods A retrospective analysis was conducted on patients with severe AIS treated in the NICU of Nanjing Drum Tower Hospital from April 2018 to December 2021. Lower extremity deep vein ultrasound examination was conducted in patients within 7 days of onset. According to the presence or absence of new CMVT, the patients were divided into non-CMVT group (n=144) and CMVT group (n=49). The incidence of CMVT and its related risk factors among patients with severe AIS were analyzed. Results The incidence of CMVT among patients with severe AIS was 24.38% (49/201). The age of patients in the CMVT group were older than that in the non-CMVT group［(74.53±9.81) years vs (69.19±14.10) years, t=2.455, P=0.015］. Proportion of patients with atrial fibrillation history was higher in the CMVT group (44.90% vs 29.17%, χ²=4.082, P=0.043). D-dimer levels in the CMVT group were significantly higher than that in the non-CMVT group［8.71 (1.58, 5.67) mg/L vs 3.09 (0.89, 3.89) mg/L, Z=2.132, P=0.038］. Univariate logistic regression analysis showed that age (OR=0.175, 95%CI: 0.035-0.309, P=0.015), history of atrial fibrillation (OR=0.145, 95%CI: 0.004-0.281, P=0.044), and D-dimer (OR=0.242, 95%CI: 0.104-0.370, P＜0.01) were correlated with the occurrence of CMVT. Multivariate logistic regression analysis showed that D-dimer was independently associated with CMVT in patients with severe AIS (OR=1.053, 95%CI: 1.005-1.104, P=0.030). Conclusion Advanced age, history of atrial fibrillation, and high level of D-dimer promote the occurrence of CMVT among patients with severe AIS, and elevated D-dimer is an independent risk factor.