Thromboembolic events are associated with prolonged clot lysis time in patients with permanent atrial fibrillation

INTRODUCTION: Atrial fibrillation (AF) is associated with a prothrombotic state. OBJECTIVES: We evaluated associations of previous thromboembolic events with fibrinolytic parameters in patients with AF. PATIENTS AND METHODS: We studied 62 consecutive patients with permanent AF (27 men, 35 women, aged 46–89 years [median, 78 years]). Patients receiving warfarin or acenocoumarol on a long‑term basis were eligible. We determined plasma fibrin clot lysis time (CLT), plasminogen activator inhibitor‑1 (PAI‑1) antigen, thrombin‑activatable fibrinolysis inhibitor (TAFI) activity and antigen, plasminogen, α2‑antiplasmin (α2AP), and soluble thrombomodulin (sTM). RESULTS: There were 19 subjects (30.6%) with a history of thrombotic events (stroke in 11, myocardial infarction in 8, and pulmonary embolism in 3 patients). They had longer CLT (P = 0.0035 for patients with previous stroke and P = 0.001 for patients with any previous thrombotic event), together with higher PAI‑1 (P = 0.025 and P = 0.016, respectively), TAFI activity (P = 0.002 and P = 0.011, respectively), sTM (P = 0.0023 and P = 0.012, respectively), and α2AP (P = 0.007 and P = 0.0006, respectively) than the remaining subjects. AF patients with previous stroke had also higher TAFI antigen than the remainder (P = 0.04). CLT (P = 0.024), PAI‑1 (P = 0.022), TAFI activity (P = 0.048), and sTM (P = 0.032, all P for trend) increased with higher CHA2DS2‑VASc scores. CLT was not associated with time from thrombotic event to enrollment. Patients taking oral anticoagulants (n = 46) had only slightly higher sTM levels (3.6 [2.9–6.3] vs. 2.9 [2.2–4.1] ng/ml, P = 0.049) than the remaining subjects. CONCLUSIONS: Stroke or other thromboembolic event in AF patients is associated with impaired lysability of fibrin clots combined with elevated PAI‑1, TAFI, sTM, and α2AP.