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Fibrinogen Level and Bleeding Risk During Catheter-Directed Thrombolysis Using Tissue Plasminogen Activator
Kevin Lee1, Alexandra Istl1, Luc Dubois1
1Division of Vascular Surgery, London Health Sciences Centre, Western University, London, Ontario, Canada.
Purpose:
The purpose of this study was to determine whether low fibrinogen levels (fibrinogen level <1.5 g/L) during catheter-directed thrombolysis are associated with an increased bleeding risk.
Methods:
A retrospective review was performed on patients undergoing extremity arterial or venous thrombolysis between 2005 and 2013.
Results:
Patients in the low fibrinogen group were younger (P = .006) and had a higher number of venous occlusive events (P = .004). The low fibrinogen group received a larger dose of tissue plasminogen activator (tPA; P = .009) and had a longer duration of thrombolysis (P = .010). The rates of major bleeding were not significantly different (P = .139). Univariate analysis showed that larger total dose and longer duration of tPA infusion were associated with increased bleeding complications (P < .01 and P = .03).
Conclusion:
A fibrinogen level <1.5 g/L during thrombolysis was not associated with an increased bleeding risk. However, larger dose and longer duration of thrombolysis were associated with increased bleeding risk.
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