Predictive Value of the Hemorrhage After Thrombolysis Score for Tissue Plasminogen Activator-Related Intracranial Hemorrhage: Emergency Department Cohort Study.

BACKGROUND

Intravenous tissue plasminogen activator (tPA) improves outcomes in acute ischemic stroke but carries a risk of intracranial hemorrhage, particularly parenchymal hematoma (PH), which is associated with poor prognosis. Early risk stratification remains clinically important.

OBJECTIVE

To evaluate the diagnostic performance of the Hemorrhage After Thrombolysis (HAT) score in predicting PH following intravenous tPA in the emergency department.

METHODS

This secondary analysis included a single-center retrospective cohort conducted between October 2023 and February 2025. Adult patients with acute ischemic stroke treated with intravenous tPA within 4.5 h were included. Baseline clinical, laboratory, and imaging data were collected. The primary outcome was PH on 24-h cranial computed tomography. Diagnostic performance was assessed using receiver operating characteristic analysis, with the optimal cutoff determined by the Youden index.

RESULTS

A total of 120 patients were included (mean age 70.2 ± 13 years; 57.5% male). PH developed in 11 patients (9.17%). HAT scores were significantly higher in the PH group (p < 0.001). The HAT score showed good discriminative performance for PH (area under the curve [AUC]: 0.871), with an optimal cutoff of 1 (sensitivity 82.6%, specificity 90.9%). For overall hemorrhagic transformation, performance was also good (AUC: 0.786). PH was associated with increased mortality and morbidity.

CONCLUSION

The HAT score demonstrates good diagnostic performance for predicting PH after thrombolysis. It may serve as a practical tool for risk stratification and post-treatment monitoring in the emergency department.