Endovascular therapy is safe, feasible, and effective in patients with stroke resulting from primary distal occlusion of the posterior cerebral artery (PCA) of the P2 or P3 segment. This is evident from the study results published in JAMA Neurology.
With limited data on the benefit of endovascular treatment for distal occlusion of medial vessels in the posterior circulation, the aim of the current study was to determine the safety of mechanical thrombectomy in stroke of the primary distal posterior cerebral artery. In addition, the study researchers attempted to compare the results of mechanical thrombectomy for an isolated posterior circulatory beat of the PCA P2 and P3 segments with the results of standard medical treatment with or without intravenous thrombolysis.
This case-control study included patients treated for primary distal occlusion of the P2 or P3 segment PCA who received mechanical thrombectomy or standard medical treatment between January 1, 2010 and June 30, 2020.
The primary result was improvement in National Institutes of Health Stroke Scale (NIHSS) scores upon release from baseline. Symptomatic intracranial bleeding and hemorrhagic complications were the safety findings.
The sample consisted of 184 patients (mean age 74 years; 48.4% men), of which 149 patients (81.0%) had a distal posterior circulation with medium vascular occlusion in the P2 segment of the PCA and 35 patients (19.0%) Occlusion in the P3 segment.
Mean NIHSS scores decreased from baseline to discharge by -2.4 points (95% CI, -3.2 to -1.6) in the standard medical treatment group and by -3.9 points (95% CI, – 5.4 to -2.5) in the endovascular treatment group (P = 0.06). In patients with a baseline NIHSS score of 10 points or more at baseline and in patients who were not eligible for intravenous thrombolysis, the mean differences in the decrease in NIHSS score in endovascular treatment compared to the standard medical treatment group were significantly higher ( P = 0.04 and P = 0.005), respectively).
The safety analysis showed that the rate of symptomatic intracerebral bleeding was 4.3% in both cohorts. The overall in-hospital mortality was 4.9% (9 of 183 patients), the 90-day mortality rate was 13.4% (18 of 134 patients), and the mortality rates did not differ significantly between the treatment groups.
The study had several limitations, including retrospective and non-randomized design, lack of data and data on the exact extent and location of the infarct tissue, and specific symptoms of distal occlusion of the posterior circulatory system.
“In this case-control study, mechanical thrombectomy was performed for the primary posterior circulation [distal, medium vessel occlusion] appeared to be appropriate, safe and technically feasible for the therapeutic treatment of occlusions of the P2 or P3 segment compared to standard medical treatment, especially when patients were out of the question [intravenous thrombolysis] or presented with high NIHSS scores (≥ 10 points), ”concluded the study researchers.
Disclosure: Several authors of the study have stated that they are part of the pharmaceutical industry. For a full list of the authors’ information, see the original reference.
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 April 1, 2021. doi: 10.1001 / jamaneurol.2021.0001