Mechanical thrombectomy appears safe and feasible for the treatment of posterior circulation distal, medium vessel occlusion (DMVO), particularly for occlusions of the P2 or P3 segment of the posterior cerebral artery (PCA), compared with standard medical management with or without intravenous thrombolysis (IVT), according to a study published in JAMA Neurology.
This retrospective study included 243 patients (median age, 74 years) from 23 comprehensive stroke centers in Europe, Asia, and the United States who were treated for primary distal occlusion of the PCA of the P2 or P3 segment. Patients in this study received either mechanical thrombectomy (n=143) or standard medical treatment (n=100) with or without IVT.
The primary clinical endpoint included the improvement of National Institutes of Health Stroke Scale (NIHSS) scores from baseline to discharge. A safety endpoint of the study included the incidence of symptomatic intracranial hemorrhage and hemorrhagic complications. The study investigators assessed the functional outcome with the modified Rankin Scale score at 90 days.
A total of 149 patients had posterior circulation DMVOs in the P2 segment, while 35 patients had posterior circulation DMVOs in the P3 segment. The mean NIHSS score decrease at discharge in the standard medical treatment cohort was -2.4 points (95% CI, -3.2 to -1.6) vs -3.9 points (95% CI, -5.4 to -2.5) in the mechanical thrombectomy group (mean difference, -1.5 points; 95% CI, 3.2 to -0.8; P =.06).
There was a significantly higher mean difference in the NIHSS score in the mechanical thrombectomy group compared with the standard medical treatment cohort for patients with NIHSS score of 10 points or greater at time of admission (mean difference, -5.6; 95% CI, -10.9 to -0.2; P =.04) and in patients without IVT (mean difference, -3.0; 95% CI, -5.0 to -0.9; P =.005).
Approximately 4.3% of patients in each treatment cohort experienced symptomatic intracranial hemorrhage.
Limitations of this study included its retrospective design and the lack of a randomized control group.
Given the limitations, the investigators suggest that a randomized controlled trial “that compares mechanical thrombectomy with standard medical treatment is warranted to evaluate the use of thrombectomy for posterior circulation DMVO and to resolve clinical equipoise in acute therapeutic decision-making.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Meyer L, Stracke CP, Jungi N, et al. Thrombectomy for primary distal posterior cerebral artery occlusion stroke: the TOPMOST study. JAMA Neurol. Published online February 22, 2021. doi:10.1001/jamaneurol.2021.0001