Risk Factors Of Hemorrhagic Transformation After Mechanical Thrombectomy Of Acute Ischemic Stroke

Background: Mechanical thrombectomy has become an effective method for the treatment of patients with acute anterior large vessel occlusion.Hemorrhagic transformation(HT)is a common complication of Mechanical thrombectomy for patients with acute ischemic stroke,but the predictors of symptomatic intracranial haemorrhage(s ICH)remains unclear.In this study,we hope to explore the risk factors for the occurrence of HT and s ICH by reviewing previous cases.Methods: the data of 160 patients with acute anterior large vessel occlusion undergoing Mechanical thrombectomy in the Department of Neurology of the Second Affiliated Hospital of Fujian Medical University between August 2016 to January2021 were reviewed retrospectively.HT and s ICH was categorized according to the Heidelberg Bleeding Classification.The possible risk factors were obtained by univariate analysis,and Stepwise logistic regression was performed to derive the s ICH predictive model.The discrimination and calibration of the risk model were assessed using the C index and the calibration plot.The discriminative performance of the predictive model were compared with the previously published risk models including the ASIAN and TAG score.Results: Of 160 patients included,HT was detected in 89 patients(55.6%),while 23 patients developed s ICH(14.4%).Univariate analysis showed that there was no significant difference in the incidence of HT and s ICH(P > 0.05)between different NIHSS score,ASPECTS score,intravenous thrombolysis,Good collaterals(ACG ≥2),good recanalization(m TICI ≥ 2b)and multiple passes with retriever(> 3 times)groups.ASIAN score and TAG score were significantly associated with a higher risk of developing any s ICH compared to no s ICH.There was significant difference in the incidence of HT between different pathogenic mechanism and the Embolization group had higher risk of hemorrhagic transformation.Blood-brain barrier destruction disruption indicated by Dyna CT was associated with higher rates of hemorrhagic transformation.Baseline glucose level,Clot Burden Score(CBS),Appearance of Early Venous Filling,blood-brain barrier destruction and Puncture to Recanalization time was associated with significantly s ICH.On multivariable analyses,appearance of Early Venous Filling(OR=8.369,95%CI2.828-24.765),CBS(OR=0.819,95%CI0.671-0.999)and baseline glucose level(OR=1.187,95%CI1.050-1.343)were predictors for s ICH.According to these three risk factors,the SICH prediction model showed a good degree of differentiation(AUC0.822)and consistency in this study population(Hosmer-Lemeshow X~2 = 4.334).The predictive model demonstrated good discrimination(AUC,0.822)and calibration(Hosmer-Lemeshow X~2 =4.334,P=0.826).For the patients in this study,the c-index of the predictive model was superior to the TAG score(0.822 vs 0.660,P=0.01),but had no significant difference with the ASIAN score(0.822 vs 0.685,P=0.11).Conclusion: Appearance of Early Venous Filling,destruction of blood-brain barrier and embolism was related to the incidence of HT after Mechanical thrombectomy,while good collaterals(ACG ≥ 2),good recanalization(m TICI ≥ 2b)and multiple passes with retriever(> 3 times),and intravenous thrombolysis was not.Appearance of Early Venous Filling,Baseline glucose level,CBS reliably predicts the risk of s ICH in patients undergoing Mechanical thrombectomy.