Background: DIRECT-SAFE (A Randomised Controlled Trial of DIRECT Endovascular Clot Retrieval versus Standard Bridging Therapy) showed improved outcomes for thrombectomy with bridging thrombolytic in the Asian region. This contrasted with other direct thrombectomy studies in Asia. We performed an analysis of regional differences to gain insight.
Methods: We analysed 295 patients from DIRECT-SAFE in Non-Asian (Australia and New Zealand) and Asian (China and Vietnam) regions, including demographics, stroke severity, time metrics, angiographic features, and clinical outcomes. Logistic regression was used to compare the effect of thrombectomy with bridging thrombolytic on outcomes in the two geographic regions.
Results: The two geographic regions were well matched for age, gender, and baseline National Institute of Health Stroke Scale. The proportion of higher Pre-morbid modified Rankin Score and presence of tandem occlusions were greater in the Asian region. Median time of stroke onset to revascularisation (203min vs 285min, p=<0.001); arrival to groin puncture (84min vs 105min, p=<0.001): and groin puncture to revascularisation (36min vs 66min, p=<0.001) were significantly shorter in the non-Asian region. Thrombectomy with a bridging thrombolytic benefited patients more in the Asian region (odds ratio of 0.42;95%CI 0.21-0.86), p=0.024) compared with the non-Asian region (odds ratio of 1.35;95%CI 0.65-2.80).
Conclusion: In the Asian region, we observed increased time delays to thrombectomy compared to those in the non-Asian region, serving as a potential explanation for the difference in clinical outcomes to thrombectomy with bridging thrombolytics in the Asian region. This provides the impetus for optimisation of in-hospital workflows to minimizing time delays.