The Problem of Restrictive Thrombectomy Trial Eligibility Criteria

Since 2015, a series of endovascular trials transformed the management of patients with large vessel occlusion stroke. Most thrombectomy trials used restrictive eligibility criteria to optimize the chances of showing that thrombectomy could work. The problem arises when generalizing trial results into evidence-based recommendations. Many organizations, oblivious of this problem, translated verbatim restrictive trial eligibility criteria into authoritative guidelines, which limit the use of thrombectomy to highly selected patients. The clinical problem becomes as follows: what to do for all other stroke patients equally in need of care? The cycle of restrictive trial eligibility criteria, corresponding restrictive guidelines, observational studies of unvalidated practices showing other patients benefit, a new trial is needed, has been repeated often. Thrombectomy trials ought to have included all patients that could potentially benefit. If the signal that was looked for by restricting eligibility is at risk of being lost in the noise generated by the heterogeneity of patients, D. Sackett proposed a solution: to use the same criteria, not to select some patients and exclude others but to prespecify the subgroup of patients most likely to benefit. In this commentary, we propose a tiered approach, where the boundaries of treatment beneficiaries can be more rigorously tested and confirmed. Identification of these patients before the development of guidelines, which would have otherwise neglected these individuals, may open innumerable treatment opportunities to those who will instead be denied of them.