Clinical evaluation of mechanical thrombectomy for patients with posterior circulation occlusion: A retrospective study

OBJECTIVE

Although consensus has been reached regarding the use of mechanical thrombectomy for acute large anterior circulation occlusion, its effectiveness in patients with posterior circulation occlusion remains unclear. This study aimed to establish the determining factors for good clinical outcomes of mechanical thrombectomy for posterior circulation occlusion.

METHODS

We extracted cases of acute large vessel occlusion (LVO) in the posterior circulation from a database comprising 536 patients who underwent mechanical thrombectomy at our hospital between April 2015 and March 2021.

RESULTS

Fifty-two patients who underwent mechanical thrombectomy for LVO in the posterior circulation were identified. Five patients with simultaneous occlusion of the anterior and posterior circulation were excluded; finally, 47 patients were included in this study. The median patient age was 78 years, and 36% of the patients were women. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 31, the median posterior circulation-Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS) was 8, and the median Basilar Artery on Computed Tomography Angiography (BATMAN) score was 6. The rate of good recanalization (Thrombolysis in Cerebral Infarction scale grades 2b and 3) was 96%, and a good prognosis (modified Rankin Scale score of 0-2 at 90 days) was achieved in 19 patients (40%). The median pc-ASPECTS was significantly higher in the good prognosis group than in the poor prognosis group (10 vs. 7; p = 0.007). The median NIHSS score at presentation was significantly lower in the good prognosis group than in the poor prognosis group (17 vs. 34; p = 0.02). The median BATMAN score was significantly higher in the good prognosis group than in the poor prognosis group (8 vs. 3.5; p = 0.0002). Multivariate analysis showed that an NIHSS score ≦ 20 at presentation was the only independent factor for good prognoses.

CONCLUSION

The prognosis of mechanical thrombectomy for posterior circulation LVO was better in patients with lower NIHSS scores at presentation.

Influencing factors of futile recanalization after endovascular therapy for cerebral infarction with posterior circulation occlusion of large vessels: a retrospective study

BACKGROUND

The optimal treatment for cerebral infarction caused by posterior circulation occlusion of large vessels has not yet been determined. Intravascular interventional therapy is an important treatment for cerebral infarction with posterior circulation occlusion of large vessels. However, endovascular therapy (EVT) of some posterior circulation cerebrovascular is ineffective and eventually become futile recanalization. Therefore, we performed a retrospective study to explore the factors influencing futile recanalization after EVT in patients with posterior circulation large-vessel occlusion.

METHODS

Eighty-six patients with acute cerebral infarction and posterior circulation large vessel occlusion after intravascular intervention were divided into two groups according to their modified Rankin scale (mRS) scores after 3 months: group 1, mRS scores less than or equal to 3 (the effective recanalization group); group 2, mRS scores greater than 3 (the ineffective recanalization group). The basic clinical data, imaging index scores, time from onset to recanalization, and operation time between the two groups were compared and analyzed. Logistic regression was used to analyze the factors influencing indicators of good prognosis, and the ROC curve and Youden index were used to determine the best cutoff value.

RESULTS

Between the two groups, there were significant differences in the posterior circulation CT angiography (pc-CTA) scores, GCS scores, pontine midbrain index scores, time from discovery to recanalization, operation time, NIHSS score and incidence of gastrointestinal bleeding. The logistic regression revealed that the NIHSS score and time from discovery to recanalization were associated with good prognoses.

CONCLUSION

NIHSS score and recanalization time were independent influencing factors of ineffective recanalization of cerebral infarctions caused by posterior circulation occlusion. EVT is relatively effective for cerebral infarction caused by posterior circulation occlusion when the NIHSS score is less than or equal to 16 and the time from onset to recanalization is less than or equal to 570 min.

Mechanical Thrombectomy for Posterior Circulation Occlusion: A Comparison of Outcomes with the Anterior Circulation Occlusion - A Meta-Analysis

Aim: There is no randomized controlled trial to compare the effectiveness and safety of mechanical thrombectomy (MT) to intravenous thrombolysis in patients with posterior circulation occlusion (PCO). Hence, we firstly performed a meta-analysis to investigate the outcomes of MT in PCO and then compared these outcomes to anterior circulation occlusion (ACO) to provide fundamental data to further studies.

Methods: We searched the PubMed, EMBASE, and Cochrane Library from dates of inception to June 2019 for relevant studies. Outcomes including functional independence at 90 days, successful recanalization, mortality, symptomatic intracranial hemorrhage (sICH), and futile recanalization were extracted.

Results: Seven studies involving 474 patients with PCO thrombectomy were analyzed. There was a lower rate of functional independence at 90 days and a higher rate of mortality after thrombectomy in PCO versus ACO (odds ratios (OR) 0.72; 95% confidence interval (CI) 0.57–0.90; OR 2.03; 95% CI 1.30–3.18). Recanalization rates were comparable (OR 1.01; 95% CI 0.62–1.65), but a higher futile recanalization rate was found in basilar artery occlusion (BAO) (OR 1.75; 95% CI 1.30–2.37). There was a lower rate of sICH in MT for patients with PCO versus ACO (OR 0.54; 95% CI 0.29–0.99).

Conclusions: We found that the outcomes of MT for patients with PCO were poorer than with ACO. On the other hand, MT appears to have lower rates of sICH and to increase successful recanalization. Given the high recanalization rate, MT may serve as an adjunct to standard treatment. The key point to improve outcomes is recognizing reliable factors associated with futile recanalization and optimizing the results of MT. But in view of the different characteristics of posterior circulation stroke and anterior circulation stroke, the results are far from robust.