By João Pedro Marto and Ellis van Etten

The first ESOC, held in Glasgow in 2015, represented a pivotal moment for stroke neurology and research. Organised by the newly formed European Stroke Organisation — dedicated to uniting international stroke researchers and clinicians within Europe with a democratic and transparent approach — the ESOC positioned itself as a leading event with 2,700 attendees in 2015, reflecting the success and collaborative spirit of the European stroke community.

The ESOC 2015 was especially significant for setting a new standard of care for patients with acute ischemic stroke and proximal anterior circulation occlusions. After the negative IMS-III trial in 2013, things started getting better with the field transitioning to a removable stent (stent retriever) device. In October 2014, the positive results of the MR CLEAN trial1 were presented at the World Stroke Conference in Istanbul. This triggered interim analyses and early termination in various ongoing RCTs focusing on mechanical thrombectomy. By early 2015, three more trials – EXTEND-IA,2 ESCAPE,3 and SWIFT PRIME4 – presented their results at the International Stroke Conference in Nashville, Tennessee.

At the 2015 ESOC, the European stroke community received more good news from three additional mechanical thrombectomy trials, along with sub-analyses from the trials presented at the WSC and ISC. The REVASCAT trial found that mechanical thrombectomy in patients with proximal anterior circulation occlusions, within 8 hours of symptoms, resulted in higher rates of functional independence at 90 days (43.7% vs. 28.2%).5 Besides, the THRACE and THERAPY results also added evidence supporting endovascular treatment benefits.6,7

Further sub-analysis on the MR CLEAN, SWIFT PRIME and ESCAPE were also presented. These studies assessed the potential differences of mechanical thrombectomy results according to sex and baseline stroke severity, and showed that some imaging markers, namely target mismatch and better collateral score, could help selecting patients that were more likely to benefit from endovascular treatment. These latter results likely contributed to the design of future trials on extended time-windows.

The ESOC 2015 was a testament to the collective efforts and dedication of the global stroke community in advancing acute stroke treatment. These trials collectively provided compelling evidence supporting the use of endovascular thrombectomy as a standard treatment approach for eligible patients with acute ischemic stroke and large vessel occlusion, leading to a paradigm shift in stroke management guidelines and clinical practice.

The ESOC renewed the determination of the attendees to reorganize their teams and prehospital care systems to promote the implementation of endovascular treatment as a cornerstone therapy in acute ischemic stroke.

References
1. Berkhemer OA, Fransen PSS, Beumer D, et al; A Randomized Trial of Intraarterial Treatment for Acute Ischemic Stroke 2015; N Engl J Med 2015; 372:11-20
2. Campbell BCV, Mitchell PJ, EXTEND-IA Investigators; Endovascular therapy for ischemic stroke N Engl J Med. 2015 Jun 11;372(24):2365-6
3. Goyal M, Demchuk AM, Menon BK, et al; Randomized assessment of rapid endovascular treatment of ischemic stroke. N Engl J Med. 2015 Mar 12;372(11):1019-30
4. Saver JL, Goyal M, Bonafe A, et al; Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke N Engl J Med 2015 Jun 11;372(24):2285-95
5. Jovin TG, Chamorro A, Cobo E, et al; REVASCAT Trial Investigators. Thrombectomy within 8 hours after symptom onset in ischemic stroke. N Engl J Med. 2015; 372:2296–2306.
6. Bracard S, Ducrocq X, Mas JL, et al; THRACE investigators. Mechanical thrombectomy after intravenous alteplase versus alteplase alone after stroke (THRACE): a randomised controlled trial. Lancet Neurol. 2016;15:1138-47.
7. Mocco J, Zaidat OO, von Kummer R, et al; THERAPY Trial Investigators. Aspiration Thrombectomy After Intravenous Alteplase Versus Intravenous Alteplase Alone. Stroke. 2016;47:2331-8