In developed countries, stroke is the third leading cause of death and the leading cause of permanent disability. Systemic and endovascular thrombolytic treatments in acute cerebral ischemic stroke caused by occlusion of large caliber vessels are currently the standard of care for the acute treatment of stroke.

The rationale of this study is to validate the results of this treatment on a large scale, in the context of what can be called "real life".

The study will have the characteristics of a descriptive observational study on patients suffering from acute ischemic stroke treated at the Policlinico A. Gemelli-IRCCS from 1 January 2016 to 31 December 2023. These data will be compared with a retrospective control group of patients undergoing mechanical thrombectomy for cerebral ischemic stroke in our polyclinic.

The primary endpoint is the outcome of patients treated with mechanical endovascular thrombectomy evaluated with the modified Ranking Scale at 90 days, while as secondary endpoints some individual characteristics of the patient will be considered (sex, age, clinical history, etc.), characteristics of the thrombus (anatomical-pathological, radiological etc) and related to acute management (therapy, rehabilitation, etc).

Background and rationale of the study In developed countries, stroke is the third leading cause of death and the leading cause of permanent disability. Recently, while some developments have been observed in the acute treatment of ischemic stroke such as the introduction of thrombolysis with rt-PA in the acute phase, in the face of acceptable side effects (NINDS, SITS MOST, ECASS), new treatments have been approved for the acute treatment of some types of acute stroke, such as endovascular treatment.

Endovascular treatment in acute cerebral ischemic stroke caused by large vessel occlusion has become the standard of care following the publication of five multicenter randomized trials performed in different reference centers in 2015. In these studies, the treatment cut-off was set at 4.5 hours, a previously validated standard time for intravenous thrombolysis, only for one of these was it instead set at 6 hours. In 2018, two other trials were published, which demonstrated the efficacy of the treatment even beyond 6 hours, one 16 hours after onset, the other up to 24 hours.

Several case studies have now been published which confirm the results of these latest trials, and others which demonstrate how the indications can be extended even beyond those envisaged by the most recent international guidelines.

The development of this therapeutic approach has therefore upset what was the standard therapy and consequently the natural history of many patients suffering from cerebral ischemic stroke.

The rationale of this study is to validate the results of this treatment on a large scale, in the context of what can be called "real life" (outside a randomized multicenter trial), as well as to define more precisely indications, contraindications , benefits (outcome at 90 days measured with the modified Ranking Scale) and possible complications of this technique. Furthermore, the presence of cofactors relating to acute management, thrombus characteristics and the data emerging from neuro-imaging performed in the acute phase that can determine better results will be evaluated.

Working hypothesis: in the various trials reported, divergences emerge in terms of characteristics of the patients enrolled, treatment timing and patient management in the acute phase. The hypothesis is that some characteristics of the patient, of the thrombus or of the type of treatment are important for the success of the treatment and their identification would allow to individualize the treatment determining better outcomes.

Inclusion Criteria:

• age > 18 years
• Acute ischemic stroke with consistent neurologic and radiologic evidence.
• Performing a CT without contrast and a triphasic CT angiography.
• Execution of mechanical endovascular thrombectomy procedure (whose indication is placed by a neurologist and interventional neuroradiologist).

Exclusion Criteria:

• patients lost to follow-up (e.g. back-transfer).

Descriptive observational study on patients with acute ischemic stroke treated at the Policlinico A. Gemelli- IRCCS from 1 January 2016 to 31 December 2023.