Thrombin generation in acute cardioembolic and non-cardioembolic ischemic stroke

Abstract

Objective. Increased thrombin generation, as measured by the Calibrated Automated Thrombogram (CAT), has recently been reported to predict ischemic stroke, especially stroke with a cardioembolic source. However, there are few studies on thrombin generation using CAT in patients with manifest ischemic stroke, particularly in patients with cardioembolic stroke not yet on anticoagulation. Materials and methods. Therefore, a prospective cohort study of 205 stroke patients > 45 years of age was performed. They were recruited during their hospital stay or shortly thereafter. Inclusion criteria were ischemic stroke or TIA within two weeks and no atrial fibrillation (AF) in the history or at inclusion. Patients received a thumb ECG device in order to detect silent AF. Blood samples were collected at inclusion and after 1 month. Thrombin generation in plasma after addition of tissue factor was assessed in patients and in healthy controls. Results. Mean age of patients was 72 ± 7 years and 43% were females. Peak thrombin concentrations were variable among stroke patients but overall significantly higher at both time points (p < 0.0001) compared to controls, and tended to be highest in patients in whom paroxysmal atrial fibrillation was subsequently documented. Conclusion. Thrombin generation in patients with acute cardioembolic and non-cardioembolic schemic stroke/TIA is variable but overall higher compared to healthy subjects. The long-term prognostic value of thrombin generation in patients with a recent ischemic stroke deserves further investigation.

Key Words::

• Ischemic stroke
• thrombin generation
• acute phase
• endogenous thrombin potential
• cardioembolic
• transient ischemic attack
• paroxysmal atrial fibrillation

Acknowledgements

The authors would like to thank the stroke-research nurses at Danderyd Hospital and Södersjukhuset (Southern hospital of Stockholm) for their valuable contribution, Elisabeth Berg at LIME, Karolinska Institutet, for her statistical support, and Katherina Aguilera and Ingrid Jacobsson for their laboratory assistance.

Sources of funding

This study was supported by the Swedish Heart and Lung foundation, the Swedish Stroke foundation, through the regional agreement on medical training and clinical research (ALF) between Stockholm County Council and the Karolinska Institutet.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.