Blood coagulation parameters in retinal arterial occlusion.
BACKGROUND
Thromboembolism is considered a crucial event in the pathogenesis of retinal occlusion, resulting in a severe damage of central or peripheral visual function.


METHODS
We evaluated hemostatic system parameters in the plasma of 14 patients (11 males and 3 females aged 59-73 years) affected by acute retinal ischemia (central retinal arterial occlusion or arterial branch occlusion). The diagnosis of retinal arterial occlusion was established according to clinical symptoms, ophthalmoscopic findings and fluorescein angiography. In addition to routine coagulation tests, antithrombin III, prothrombin fragment 1+2 (F1+2), thrombin-antithrombin III complex (TAT), and D-dimer were measured in the plasma both at the moment of diagnosis (before therapy initiation) and 3-6 months later (at least 1 months after antithrombotic therapy discontinuation).


RESULTS
We found a marked increase in the plasma levels of F1+2, TAT, and D-dimer during the acute event, compared with healthy control values. F1+2 and TAT significantly decreased during follow-up, whereas D-dimer was unchanged.


CONCLUSIONS
Our data indicate accelerated conversion of prothrombin to thrombin (high F1+2) and an increase in circulating thrombin (high TAT) during retinal arterial occlusion, providing evidence that increased thrombin generation may play a role in acute retinal ischemia.
Sagripanti
A
A
Clinica Medica I, Ospedale S. Chiara, Pisa, Italy.
Romani
A
A
Ferretti
A
A
Ragone
M C
MC
Baicchi
U
U
Carpi
A
A
Nardi
M
M
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D000933:Antifibrinolytic Agents / Q000378:metabolism; D000990:Antithrombin III / Q000378:metabolism; D001777:Blood Coagulation / Q000502:physiology*; D002784:Cholesterol / Q000097:blood; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D017270:Lipoprotein(a) / Q000097:blood; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism; D011516:Prothrombin / Q000378:metabolism; D015356:Retinal Artery Occlusion / Q000097:blood / Q000503:physiopathology*
D000933:Antifibrinolytic Agents; D005338:Fibrin Fibrinogen Degradation Products; D017270:Lipoprotein(a); D010446:Peptide Fragments; D011498:Protein Precursors; C046193:antithrombin III-protease complex; C036309:fibrin fragment D; C029733:prothrombin fragment 1; C044183:prothrombin fragment 2; D000990:Antithrombin III; D011516:Prothrombin; D005340:Fibrinogen; D002784:Cholesterol; D010447:Peptide Hydrolases