ADAPT First-Line Strategy for MCA Mainstem Occlusion; Analysis for Optimal Salvage Therapy and its Related Factor

Objectives: A direct first-pass aspiration technique (ADAPT) is an attractive interventional technique for mechanical thrombectomy (MT), which could achieve recanalization quickly and safely at a small amount of material resources. To clarify its usefulness, our ADAPT first-line strategy for middle cerebral artery (MCA)-mainstem occlusion was retrospectively analyzed.

Materials and methods: We reviewed 54 consecutive patients who underwent MT for MCA-mainstem occlusion using ADAPT first-line strategy. A salvage procedure was concurrently conducted in cases that failed to achieve successful recanalization by ADAPT attempt alone. Procedural and clinical outcome were assessed in both ADAPT alone and Salvage groups. Further investigation was performed in cases that required salvage procedure to determine the reason, risk factors, and optimal procedure.

Results: Forty-one patients (75.9%) were able to achieve successful recanalization with ADAPT technique alone. In salvage group, the procedural time was longer, and rates of successful recanalization were lower than in ADAPT-alone group. No significant difference in the rates of favorable outcomes was observed. Among 13 patients who required salvage therapy, the major reason (eight cases) was intra-procedural "thrombus distal migration". Failure of recanalization was seen in two cases due to "inaccessibility". In patients who had "thrombus distal migration", occlusion in the proximal portion was more frequently observed than in patients who did not (p = 0.032, 63.6% vs. 23.3%).

Conclusions: Our ADAPT first-line strategy for MCA-mainstem occlusion demonstrated favorable procedural and clinical outcomes, even in cases that required additional procedures. Further investigation and better understanding are required to refine this promising procedure.