A Comparative Study of Hemorrhagic Conversion Patterns After Stroke Thrombolysis With Alteplase Versus Tenecteplase

Background and purpose: Tenecteplase is the thrombolytic drug of choice for acute ischemic stroke (AIS) as it has unique pharmacologic properties, along with results demonstrating its non-inferiority compared to alteplase. However, there are contradictory data concerning the risk of intracranial hemorrhage. The purpose of the study was to report the rate and patterns of symptomatic intracranial hemorrhage (sICH) in AIS patients after thrombolysis with tenecteplase compared to alteplase. Methods: This is a retrospective cohort study with data collected 90 days before and after the change from alteplase to tenecteplase from 15 Texas stroke centers. The primary endpoint is the incidence of sICH according to the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) and European Cooperative Acute Stroke Study III (ECASS-3) criteria. The secondary endpoints are the radiographic pattern of hemorrhagic conversion according to the Heidelberg bleeding classification (HBC). Results: A total of 431 patients were eligible for thrombolytic therapy. Half of the cohort received alteplase (n=216), and the other half received tenecteplase (n=215). The average age of the alteplase group was 62.94 years old (SD=15.12) and 64.45 years old (SD=14.51) for the tenecteplase group. Seven patients in the alteplase group (3.2%) and 14 (6.5%) in the tenecteplase group had sICH, with an odds ratio of 1.44 (95% CI 0.60-3.43; P=0.41). An increased National Institutes of Health Stroke Scale (NIHSS) score on arrival (1.06; 95% CI 1.0004-1.131; P=0.04) was a statistically significant predictor of sICH. Tenecteplase was associated with a statistically significant increase in HBC-3 (P=0.040) over alteplase. Conclusions: Compared with alteplase, our study revealed a higher rate of sICH with tenecteplase that was not statistically significant and a higher rate of HBC-3 hemorrhages that was statistically significant. The proposed mechanism of bleeding is hemorrhagic conversion in clinically silent infarcts and contusions underlying the lesions. Further studies are needed to confirm our findings and determine predictive risk factors.