Thrombectomy for M1-Middle Cerebral Artery Occlusion: Angiographic Aspect of the Arterial Occlusion and Recanalization: A Preliminary Observation

Background and purpose: Despite the recent technical evolution of the endovascular treatment of acute ischemic stroke, late and incomplete recanalization can be achieved after several maneuvers but with a potentially higher risk of futile reperfusion and complications, such as clot fragmentation. The aim of this article is to investigate the impact of the angiographic phenotype of M1-middle cerebral artery occlusions, classified as regular and irregular in aspect, on the results of treatment by stent retrievers (SRs) or contact aspiration (CA).

Methods: From January to April 2016, 84 consecutive patients, admitted for acute ischemic stroke with a middle cerebral artery occlusion, were treated by endovascular therapy. Among them, 60 patients (26M, 34F, median age, 70.5; interquartile range, 58.5-80.0) were treated by SR (25/60, 41.7%) or CA (35/60, 58.3%) as a first-line approach in 2 experienced centers. Patients' characteristics, timing, and procedural data were prospectively recorded and compared between the 2 study subgroups (regular and irregular phenotype).

Results: A regular phenotype at the occlusion site was observed in 24 patients (40%). Among these, successful recanalization after the first-line strategy (Thrombolysis in Cerebral Infarction 2b-3) was achieved in 100% of patients treated by CA and in only 33.3% of patients treated by SR (P=0.001). For irregular phenotypes, SR achieved Thrombolysis in Cerebral Infarction 2b-3 in 73.9% and CA, in 38.5% (P=0.036) of cases. Among regular phenotype patients, the average number of maneuvers was 1.3 (median, 1; range 1-3) with first-line CA and 2.7 (median, 3; range 1-5) with first-line SR (P=0.008).

Conclusions: The angiographic phenotype of the occlusion site may be associated with a different response to SR and CA in this preliminary experience.