Thrombin generation in the acute phase of ST-Elevation Myocardial Infarction

Introduction

Thrombin generation (TG) is an increasingly recognized measurement, providing insight into the coagulation characteristics of a patient. The hypercoagulable state in the acute phase of a ST Elevation Myocardial Infarction (STEMI) is of significant clinical importance. Importantly, despite advanced therapeutics, a residual ischemic risk remains amongst these patients. The TG of this condition is yet to be described and could help provide a greater understanding of this pathway and help to guide future clinical management.

Methods and Materials

Thrombin generation (TG) was measured in vitro using CAT (Calibrated automated thrombogram) in patients presenting with STEMI to our institution. TG was measured both at the initial time of presentation (before percutaneous intervention) and 24 hours later. Four parameters of the thrombogram were analysed- the time of the lag phase until the initiation of thrombin generation, the thrombin peak, the time to reach the peak and the area under the curve (AUC, defined as the Endogenous Thrombin Potential)

Results and Discussion

Our cohort included 43 patients. The mean age was 57.62+-12.6 years, 79% male. Initial results show that the time of the lag phase and time to peak were longer at baseline compared to that 24 hours later (7.82 minutes vs 5.30 minutes, p=0.012; and 9.73 minutes vs 9.42 minutes, p=0.818, respectively). The thrombin peak was significantly higher at 24 hours compared to the level at baseline (532.40 vs 371.44 nmol/L, p=0.004). The AUC was also significantly greater after 24 hours compared to that at baseline (2374.66 vs 1692.02, p=0.045).

Conclusion

Our results indicate that markers of TG are still markedly elevated 24 hours after the initial presentation of STEMI. These dynamic changes in TG during STEMI could have clinical implications, explaining some of the residual risk associated with this high-risk medical emergency.