====== Secondary embolism ======

Secondary [[embolism]] (SE) during [[mechanical thrombectomy]] (MT) for [[acute ischemic stroke]] (AIS) is the main reason for incomplete [[recanalization]], while its [[risk factor]]s are largely unknown. 

A study of Ye et al. addresses a potential relationship between [[thrombus]] density on preinterventional [[computed tomography]] (CT) and the occurrence of SE.

They reviewed [[anterior circulation]] AIS patients who underwent MT from July 2015 to January 2019 in the [[Beijing]] Hospital. Thrombus density was measured in [[Hounsfield Unit]]s (HU) on 1-mm and 5-mm preinterventional nonenhanced CT (NECT). Thrombus density, baseline characteristics, procedural, and clinical outcomes were compared between patients with SE and those without SE. [[Logistic regression]] was conducted to identified potential risk factors of SE.
:
Sixty-four consecutively patients were included, of whom SE was identified in 16 (25.0%) patients. Compared with those without SE, patients with SE showed a higher thrombus density on both 1-mm (72.85 versus 64.28, P = .005) and 5-mm NECT (60.31 versus 49.71, P < .001), a higher proportion of atrial fibrillation (75.0% versus 45.8%, P = .043), a lower clot burden score (.5 versus 6.0, P = .029), and a higher proportion of front-line contact aspiration strategy (50.0% versus 16.7%, P = .020). Multivariate regression analysis showed that only thrombus density was the independent predictor of SE (for the model including HU values on 1-mm NECT, OR 1.11, 95%CI 1.01-1.23, P = .029; for the model including HU values on 5-mm NECT, OR 1.09, 95%CI 1.02-1.17, P = .018).

Higher thrombus density was the independent predictor for [[secondary embolism]]. Further studies are needed to investigate its role in the optimization of [[mechanical thrombectomy]] strategy
((Ye G, Cao R, Lu J, Qi P, Chen J, Wang D. CT-based Higher Thrombus Density is
associated with Secondary Embolism during Mechanical Thrombectomy: A Preliminary 
Observation. J Stroke Cerebrovasc Dis. 2019 Jul 31:104311. doi:
10.1016/j.jstrokecerebrovasdis.2019.104311. [Epub ahead of print] PubMed PMID:
31376998.
)).