Elena Zapata-Arriaza, MD

Baek JH, Kim BM, Heo JH, Kim DJ, Nam HS, Kim YD. Outcomes of Endovascular Treatment for Acute Intracranial Atherosclerosis–Related Large Vessel Occlusion. Stroke. 2018

In this entry, I discuss a recent publication by Jang-Hyun Baek and colleagues regarding the endovascular and clinical outcomes of patients with Acute Intracranial Atherosclerosis–Related Large Vessel Occlusion, treated with endovascular therapy.

The introduction of retrievable stents as first choice technique for endovascular therapy in acute ischemic stroke has allowed a high recanalization rate, and has been associated with a good clinical outcome. However, the etiology of stroke may affect the success of the mentioned recanalization technique.

The authors performed a retrospective review in a single stroke center in an Asian country of procedural and clinical results in the anterior circulation stroke cases with emergent large vessel occlusion (LVO) eligible for endovascular treatment (EVT). The significant new of the paper is the division of the sample and the results regarding the occurrence or not of intracranial atherosclerosis (ICAS) associated to LVO [ICAS +/-LVO]. Among the 318 patients who underwent endovascular therapy for acute intracranial LVO in the anterior circulation, 56 (17.6%) had ICAS (+)-LVO. Recanalization rates defined as TICI 2b-3 were similar between ICAS (+)-LVO and ICAS (-)-LVO (80.4% vs  88.5%; P =0.097) respectively, and the authors didn’t find significant differences between the 2 groups in terms of favourable outcome (46.4% versus 46.9%; P=0.944), death (19.6% versus 15.3%; P=0.418) and symptomatic intracranial hemorrhage (sICH) (5.4% versus 5.0%, P=0.902).

In a more detailed analysis, this article describes valuable data in order to improve our knowledge about ICAS (+)-LVO management. The authors found successful recanalization using a stent retriever in 93.5% of patients (n=217) in the ICAS (-)-LVO group and only in 28.9% of patients (n=13) in the ICAS (+)-LVO group (P<0.001). The remaining patients in the ICAS (+)-LVO group (n=32; 71.1%) achieved recanalization using rescue treatments. In 27 of the mentioned 32 patients, the presence of underlying intracranial atherosclerotic stenosis required more complex endovascular therapy (balloon angioplasty, stenting, and intra-arterial GPI infusion or the combination between them). 11 of 27 achieved a successful recanalization using only Glycoprotein inhibitor (GPI), and 15 patients also required rescue stenting. Finally, reocclusion events were observed more frequently in the ICAS (+)-LVO group than in the ICAS (-)-LVO group. Overall, 77.3% of reocclusion was successfully recanalized by GPI and consecutive stenting with/without balloon angioplasty.

Interesting reading can be obtained from this article. First, it seems that recanalization rates between subgroups are similar, although the way to resolve the occlusion differs according to the underlying cause. Given this paper, the presence or the suspicion of ICAS would advise us that stentriever will not be effective enough in these cases, so interventionists should add different techniques with greater complexity and time consumption for the procedure. Second, the authors suggest that recanalization condition would be considered as a more relevant factor affecting a patient’s functional outcome than the occlusion pathogenesis. This interesting advice generates more considerable questions: How many attempts should we try to achieve recanalization? Should we try to solve the occlusion regardless of the time consumption? What antiplatelets strategy should we use, and when should we use it to obtain a fast recanalization, avoid reocclusion and stabilize the plaque?

This article offers relevant and easy suggestions to apply to our daily clinical practice, like waiting 20 minutes in patients with ICAS before completing the procedure, to monitor and treat reocclusion early, or a strategy from less to more complex technique to rescue the occlusion. Finally, this study is a valuable starting point to address the problem in non-Asian patients and to propose randomized studies in the future.