Elevated thrombin generation capacity is associated with worse 90-day outcomes in acute ischemic stroke patients treated with r-tPA, and may promote formation of denser, thrombolysis-resistant thrombi.
Thrombin generation capacity was significantly greater in stroke patients with worse 90-day functional outcomes compared to those with good outcomes.
The association between thrombin generation capacity and worse outcome remained significant after adjustment for multiple clinical covariates.
In vitro, increased thrombin was associated with denser fibrin clot structure and prolonged clot lysis time in response to tPA.
Peak thrombin levels positively correlated with inflammatory and coagulation markers in stroke patients.
Peak thrombin levels were inversely correlated with α2-macroglobulin (α2M) levels in stroke patients.
Thrombin generation capacity was proposed as a potential biomarker for risk stratification and prediction of thrombolytic response variability in stroke patients.
This research suggests that the blood's capacity to generate thrombin — a protein central to blood clot formation — is linked to how well stroke patients recover after receiving the clot-dissolving drug r-tPA (also called alteplase). In a study of 78 stroke patients, those who had worse functional outcomes three months after their stroke had significantly higher thrombin generation levels in their blood compared to those who recovered well (254 nM versus 210 nM). This relationship held up even after accounting for other known risk factors like stroke severity, age, sex, and heart rhythm problems. The study also found a likely biological explanation for why higher thrombin levels might lead to worse outcomes: in laboratory experiments, more thrombin caused blood clots to form with a denser, tighter structure that was harder for r-tPA to dissolve. In patients, higher thrombin levels were also associated with elevated levels of inflammatory proteins (IL-6 and IL-8) and fibrinogen (a clotting protein), as well as lower levels of α2-macroglobulin, a natural thrombin inhibitor. Together, these findings paint a picture of a pro-clotting, pro-inflammatory state that makes thrombolytic therapy less effective. This research suggests that measuring thrombin generation before or after giving r-tPA could help doctors identify which stroke patients are at higher risk for poor recovery and may need additional or alternative treatments. It also points to thrombin generation as a potential explanation for why some patients respond well to r-tPA while others do not — a question that has long puzzled clinicians. If confirmed in larger studies, thrombin generation capacity could become a useful tool for personalizing stroke treatment.
Falcione S, Joy T, Munsterman D, Sai S, Boghozian R, Jickling G. (2026). Thrombin Generation Capacity is Associated With Worse Outcome in r-tPA Treated Patients With Stroke.. Translational stroke research. https://doi.org/10.1007/s12975-026-01490-1