“Chopperlysis”: The effect of helicopter transport on reperfusion and outcomes in large vessel occlusion strokes

Background: In large vessel occlusion (LVO) stroke patients transferred to a comprehensive stroke center for thrombectomy, spontaneous reperfusion may occur during transport, and anecdotally more frequently in patients transferred via helicopter than by ground. This pattern has been more often observed in conjunction with tenecteplase (TNK) treatment prior to helicopter transport. We aim to explore the “chopperlysis” effect—how helicopter transport, particularly with thrombolytics, may affect reperfusion and clinical outcomes. Methods: A single thrombectomy capable center (TCC) registry of stroke patients was retrospectively reviewed. Included LVO patients were those who had been transferred to the TCC and received a digital subtraction angiography (DSA) upon arrival. The outcomes were rates of spontaneous reperfusion, distal clot migration, and 90-day good functional outcome. Data were summarized, and endpoints were compared between patients stratified by transport method and/or TNK treatment. Results: Of 270 patients included, helicopter transport was associated with a higher rate of spontaneous reperfusion, particularly among patients not treated with TNK (p < 0.001). There was no significant difference in prevalence of distal clot migration between any subgroups (p > 0.37). Overall, TNK-treated patients had better functional outcomes, and this difference persisted exclusively in the helicopter-transported patients (p = 0.02). Conclusion: Helicopter transport was associated with a higher rate of spontaneous reperfusion. There is a potentially synergistic effect between TNK administration and helicopter transport, augmenting thrombolysis and improving long-term outcomes. Further analyses in larger cohorts may expand our understanding of this “chopperlysis” effect.