Early decrease in coagulation activity after myocardial infarction is associated with lower risk of new ischaemic...

Area of Science:

• Cardiology
• Thrombosis Research
• Pharmacology

Background:

• Patients post-myocardial infarction face elevated risks of recurrent ischemic events.
• The ESTEEM trial demonstrated ximelagatran's efficacy in reducing these events compared to placebo in aspirin-treated patients.
• Ximelagatran effectively lowered coagulation markers like prothrombin fragment 1 + 2 (F1 + 2) and D-dimer.

Purpose of the Study:

• To evaluate coagulation markers (F1 + 2, D-dimer) and activated thromboplastin time (APTT) in relation to new ischemic events and bleeding.
• To determine if baseline coagulation marker levels predict treatment response to ximelagatran.
• To assess the impact of D-dimer reduction on ischemic event risk, irrespective of treatment.

Main Methods:

• A substudy included 518 patients randomized to ximelagatran or placebo for 6 months post-myocardial infarction.
• Coagulation markers (F1 + 2, D-dimer) and APTT were measured at randomization and serially.
• Clinical endpoints included death, myocardial infarction, recurrent ischemia, stroke, and bleeding.

Main Results:

• Ximelagatran showed a greater effect in patients with above-median F1 + 2 and D-dimer levels at randomization, reducing ischemic events significantly.
• A reduction in D-dimer levels within 1 week post-randomization correlated with fewer ischemic events, regardless of treatment.
• Elevated APTT in the ximelagatran group was linked to increased bleeding risk but not ischemic events.

Conclusions:

• Decreased D-dimer levels in post-myocardial infarction patients indicate a lower risk of new ischemic events, whether spontaneous or treatment-induced.
• Patients with initially higher coagulation activity appear to derive the most benefit from long-term ximelagatran treatment.
• Monitoring D-dimer reduction can identify patients at lower risk for recurrent ischemia.