Precision medicine for futile recanalization after mechanical thrombectomy in acute ischemic stroke: mechanisms, diagnostics, and tailored therapies

Mechanical thrombectomy has substantially improved outcomes in appropriately selected patients with acute ischemic stroke, yet futile recanalization remains a major clinical challenge. Futile recanalization describes poor functional recovery despite technically successful macrovascular reperfusion, underscoring the incomplete relationship between angiographic reperfusion and tissue-level or microvascular perfusion. This narrative review summarizes current clinical, mechanistic, and translational evidence on the determinants of futile recanalization and evaluates emerging precision-medicine approaches to its prevention and management. Precision imaging has established a role in tissue-based patient selection, and recent randomized trials have expanded thrombectomy evidence to selected patients with large-core infarction. In contrast, current randomized evidence does not support routine endovascular treatment for unselected medium-vessel occlusion populations. We further examine bridging therapy versus direct mechanical thrombectomy, individualized periprocedural management, biomarkers, and decision support based on artificial intelligence. Clinical and imaging phenotypes may provide prognostic or mechanistic information, but no phenotype-based strategy has been prospectively validated to select bridging therapy or direct thrombectomy. Biomarkers currently remain primarily prognostic or exploratory. Artificial intelligence applications are largely focused on diagnostic and prognostic support. treatment-benefit prediction, by contrast, requires evidence of treatment-effect modification and prospective validation. Experimental studies of microvascular no-reflow and thrombo-inflammation provide biological rationale for targeted interventions but do not establish clinical efficacy. Future research should integrate multimodal imaging, biological profiling, and validated decision-support tools to move beyond angiographic success toward individualized strategies focused on tissue integrity and meaningful functional recovery.