Fibrinolytic activity in retinal vein occlusion.
OBJECTIVE
Impaired fibrinolytic function is a common finding in patients with thrombotic disease. The present study was initiated to evaluate the fibrinolytic response to a venous occlusion test (VOT) in patients with retinal vein occlusion.


METHODS
Euglobulin clot lysis time (ECLT), tissue plasminogen activator (t-PA) activity, and plasminogen activator inhibitor (PAI) activity were measured before and after VOT in a group of 26 consecutive patients presenting with retinal vein occlusion and in 15 healthy age- and sex-matched controls.


RESULTS
Before VOT (baseline), a higher proportion of patients (54%) had an ECLT of more than 5 h compared with controls (6.7%) (p = 0.0027) indicating decreased overall fibrinolytic activity. Patients had non-significantly lower t-PA and higher PAI activities compared with controls. After VOT, a higher proportion of patients (34.6%) had an ECLT of more than 5 h compared with controls (6.7%) (p = 0.05). Patients had significantly lower t-PA activity (p = 0.0232) and significantly higher PAI activity (p = 0.0292). Subgroup analysis revealed that patients with an ECLT of more than 5 h had significantly higher levels of PAI activity at baseline (p = 0.0326) and after VOT (p = 0.0184) compared with patients with an ECLT of less than 5 h. However, t-PA activity was significantly higher (p = 0.0153) at baseline, and non-significantly higher after VOT in patients with an ECLT of more than 5 h when compared with patients with an ECLT of less than 5 h.


CONCLUSIONS
These findings suggest that impaired fibrinolysis due to increased PAI activity may play a role in the pathogenesis of retinal vein occlusion.
Abu El-Asrar
A M
AM
Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia. abuasrar@KSU.edu.sa
Abdel Gader
A G
AG
Al-Amro
S
S
Al-Momem
A K
AK
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003018:Clot Retraction; D005260:Female; D005342:Fibrinolysis / Q000502:physiology; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D008297:Male; D008875:Middle Aged; D015849:Plasminogen Inactivators / Q000097:blood; D011446:Prospective Studies; D012170:Retinal Vein Occlusion / Q000097:blood* / Q000175:diagnosis / Q000209:etiology; D012712:Serum Globulins / Q000378:metabolism; D010959:Tissue Plasminogen Activator / Q000097:blood; D014792:Visual Acuity
D015415:Biomarkers; D015849:Plasminogen Inactivators; D012712:Serum Globulins; D010959:Tissue Plasminogen Activator