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Updated: Apr 19, 2026

A Fibrin-Enriched and tPA-Sensitive Photothrombotic Stroke Model
Published on: June 4, 2021
Fibrinogen decrease after intravenous thrombolysis in ischemic stroke patients is a risk factor for intracerebral
Laura Vandelli1, Marco Marietta2, Mariaelena Gambini3
1Stroke Unit, Department of Neuroscience, University of Modena and Reggio Emilia, Nuovo Ospedale Civile S. Agostino-Estense, AUSL Modena, Modena, Italy.
Background:
Intravenous thrombolysis is an effective treatment in acute stroke patients, but it increases the risk of intracerebral hemorrhages. Our aim is to establish if fibrinogen depletion increases the risk of intracerebral hemorrhage after intravenous thrombolysis for acute ischemic stroke.
Methods:
In 104 ischemic stroke patients, treated with intravenous thrombolysis, we assessed the rate of intracerebral hemorrhages documented by computed tomographic scan at 24 hours and within 7 days post-treatment. Fibrinogen levels were determined at 2 hours after therapy: patients were classified as belonging to "low fibrinogen group" if levels decreased to less than 2 g/L and/or by 25% or more. Fibrinogen levels and other known hemorrhagic risk factors were studied using univariate and multivariate analyses.
Results:
During the first 7 days, an intracerebral hemorrhage was detected in 24 patients (23.1%), and only 6 of these (5.8%) experienced symptomatic bleeding; 41 patients were included in the low fibrinogen group. Among the 24 hemorrhages, 18 occurred in the low fibrinogen group and 6 in the "normal fibrinogen group": the bleeding rate in the low fibrinogen group was significantly higher (43.9%) than that in the normal fibrinogen group (9.5%; odds ratio [OR] 7.43, P < .001). Univariate and multivariate analyses revealed that only clinical severity (OR 1.15, P < .001) and hypofibrinogenemia (OR 7.47, P < .001) were significantly associated with brain bleeding at 7 days and at 24 hours (P = .008).
Conclusions:
An early fibrinogen reduction seems to increase the risk of intracerebral hemorrhage after rtPA treatment in ischemic stroke. Fibrinogen assessment could be a rapid, inexpensive, and widely available tool to help the identification of patients at higher risk of bleeding.
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