Key to better outcomes in stroke intervention: early versus complete reperfusion in first pass recanalization.

Background and purpose: First pass (FP) recanalization, defined as achieving mTICI 2b or higher in a single thrombectomy attempt, has been linked to better functional recovery in acute ischemic stroke patients. This study aimed to investigate whether the benefits of FP are primarily driven by higher rates of complete reperfusion (mTICI 3) or by faster procedure times.

Methods: Data from 3707 patients with middle cerebral artery occlusion and successful recanalization (mTICI 2b or higher) were extracted from the prospectively designed German Stroke Registry (2015-2021). Good functional outcomes were defined as a modified Rankin Scale (mRS) score of ≤ 2 at 90 days. Mediation analysis was used to evaluate the extent to which complete reperfusion (mTICI 3) and shorter groin puncture to recanalization time contributed to improved outcomes.

Results: FP recanalization was associated with significantly better functional outcomes: 46.9% of FP patients achieved an mRS ≤ 2 compared to 37.2% in the multi-pass group. Mediation analysis showed that only 14% of the improved outcomes with FP were explained by higher mTICI 3 rates, while 37% were attributed to faster recanalization times.

Conclusion: The improved outcomes associated with FP recanalization are primarily driven by the speed of reperfusion rather than the degree of complete recanalization. This highlights the importance of minimizing procedure times and the number of thrombectomy attempts. Strategies aimed at optimizing treatment workflows and improving device design to prioritize early and efficient reperfusion after the FP are critical to improving patient outcomes (ClinicalTrials.gov identifier: NCT03356392).