Mechanical thrombectomy appears safe and feasible for the treatment of the distal, middle vascular occlusion (DMVO) of the posterior circulatory system, especially for occlusions of the P2 or P3 segment of the posterior cerebral artery (PCA), compared to standard medical treatment with or without intravenous thrombolysis ( IVT), according to a study published in JAMA Neurology.
This retrospective study enrolled 243 patients (mean age 74 years) from 23 major stroke centers in Europe, Asia and the USA 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 was improvement in National Institutes of Health Stroke Scale (NIHSS) scores from baseline to discharge. A safety endpoint of the study was the occurrence of symptomatic intracranial bleeding and hemorrhagic complications. The investigators of the study assessed the functional result with the modified Rankin Scale Score after 90 days.
A total of 149 patients had posterior circulatory DMVOs in the P2 segment, while 35 patients had posterior circulatory DMVOs in the P3 segment. The mean decrease in NIHSS at discharge in the standard medical treatment cohort was -2.4 points (95% CI, -3.2 to -1.6) versus -3.9 points (95% CI, -5.4 to -2.5) in the group of mechanical thrombectomy (mean) difference -1.5 points; 95% CI 3.2 to -0.8; P = 0.06).
There was a significantly higher mean difference in NIHSS score in the mechanical thrombectomy group compared to the standard medical treatment cohort in patients with an NIHSS score of 10 points or more at admission (mean difference -5.6; 95% CI -10.9) to -0.2; P = 0.04) and in patients without IVT (mean difference -3.0; 95% CI -5.0 to -0.9; P = 0.005).
Approximately 4.3% of the patients in each treatment cohort had symptomatic intracranial bleeding.
The limitations of this study included the retrospective design and the lack of a randomized control group.
Given the limitations, the researchers suggest that a randomized controlled trial “comparing mechanical thrombectomy with standard medical care is warranted to evaluate the use of thrombectomy for DMVO in the posterior circulation and to remedy the clinical balance in acute therapeutic decisions “.
Disclosure: Several authors of the study have stated that they are part of the pharmaceutical industry. See the original reference for a full list of what the authors said.
Meyer L., Stracke CP, Jungi N. et al. Thrombectomy for primary occlusion of the distal posterior cerebral artery: the TOPMOST study. JAMA Neurol. Published online February 22, 2021. doi: 10.1001 / jamaneurol.2021.0001