Prognostic impact of hypercoagulability and impaired fibrinolysis in acute myocardial infarction

Aims Atherothrombotic events are influenced by systemic hypercoagulability and fibrinolytic activity. The present study evaluated thrombogenicity indices and their prognostic implications according to disease acuity. Methods and results From the consecutive patients undergoing percutaneous coronary intervention (PCI), those with thrombogenicity indices (n = 2705) were grouped according to disease acuity [acute myocardial infarction (AMI) vs. non-AMI]. Thrombogenicity indices were measured by thromboelastography (TEG). Blood samples for TEG were obtained immediately after insertion of the PCI sheath, and TEG tracing was performed within 4 h post-sampling. Major adverse cardiovascular events (MACE, a composite of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke) were evaluated for up to 4 years. Compared with non-AMI patients, AMI patients had higher platelet-fibrin clot strength [maximal amplitude (MA): 66.5 +/- 7.8 vs. 65.3 +/- 7.2 mm, P < 0.001] and lower fibrinolytic activity [clot lysis at 30 min (LY30): 0.9 +/- 1.8% vs. 1.1 +/- 1.9%, P < 0.001]. Index AMI presentation was associated with MA [per one-mm increase: odds ratio (OR): 1.024; 95% confidence interval (CI): 1.013-1.036; P < 0.001] and LY30 (per one% increase: OR: 0.934; 95% CI: 0.893-0.978; P = 0.004). The presence of high platelet-fibrin clot strength (MA >= 68 mm) and low fibrinolytic activity (LY30 < 0.2%) was synergistically associated with MACE occurrence. In the multivariable analysis, the combined phenotype of 'MA >= 68 mm' and 'LY30 < 0.2%' was a major predictor of post-PCI MACE in the AMI group [adjusted hazard ratio (HR): 1.744; 95% CI: 1.135-2.679; P = 0.011], but not in the non-AMI group (adjusted HR: 1.031; 95% CI: 0.499-2.129; P = 0.935). Conclusion AMI occurrence is significantly associated with hypercoagulability and impaired fibrinolysis. Their combined phenotype increases the risk of post-PCI atherothrombotic event only in AMI patients. These observations may support individualized therapy that targets thrombogenicity for better outcomes in patients with AMI.