Thrombectomy for Primary Distal Posterior Cerebral Artery Occlusion Stroke

Abstract

IMPORTANCE Clinical evidence of the potential treatment benefit of mechanical thrombectomy for posterior circulation distal, medium vessel occlusion (DMVO) is sparse.OBJECTIVE To investigate the frequency as well as the clinical and safety outcomes of mechanical thrombectomy for isolated posterior circulation DMVO stroke and to compare them with the outcomes of standard medical treatment with or without intravenous thrombolysis (IVT) in daily clinical practice. DESIGN, SETTING, AND PARTICIPANTSThis multicenter case-control study analyzed patients who were treated for primary distal occlusion of the posterior cerebral artery (PCA) of the P2 or P3 segment. These patients received mechanical thrombectomy or standard medical treatment (with or without IVT) at 1 of 23 comprehensive stroke centers in Europe, the United States, and Asia between January 1, 2010, and June 30, 2020. All patients who met the inclusion criteria were matched using 1:1 propensity score matching. INTERVENTIONS Mechanical thrombectomy or standard medical treatment with or without IVT.MAIN OUTCOMES AND MEASURES Clinical end point was the improvement of National Institutes of Health Stroke Scale (NIHSS) scores at discharge from baseline. Safety end point was the occurrence of symptomatic intracranial hemorrhage and hemorrhagic complications were classified based on the Second European-Australasian Acute Stroke Study (ECASSII). Functional outcome was evaluated with the modified Rankin Scale (mRS) score at 90-day follow-up. RESULTSOf 243 patients from all participating centers who met the inclusion criteria, 184 patients were matched. Among these patients, the median (interquartile range [IQR]) age was 74 (62-81) years and 95 (51.6%) were female individuals. Posterior circulation DMVOs were located in the P2 segment of the PCA in 149 patients (81.0%) and in the P3 segment in 35 patients (19.0%). At discharge, the mean NIHSS score decrease was −2.4 points (95% CI, −3.2 to −1.6) in the standard medical treatment cohort and −3.9 points (95% CI, −5.4 to −2.5) in the mechanical thrombectomy cohort, with a mean difference of −1.5 points (95% CI, 3.2 to −0.8; P = .06). Significant treatment effects of mechanical thrombectomy were observed in the subgroup of patients who had higher NIHSS scores on admission of 10 points or higher (mean difference, −5.6; 95% CI, −10.9 to −0.2; P = .04) and in the subgroup of patients without IVT (mean difference, −3.0; 95% CI, −5.0 to −0.9; P = .005). Symptomatic intracranial hemorrhage occurred in 4 of 92 patients (4.3%) in each treatment cohort.CONCLUSIONS AND RELEVANCE This study suggested that, although rarely performed at comprehensive stroke centers, mechanical thrombectomy for posterior circulation DMVO is a safe, and technically feasible treatment option for occlusions of the P2 or P3 segment of the PCA compared with standard medical treatment with or without IVT.

Mechanical Thrombectomy in Isolated Occlusion of the Proximal Posterior Cerebral Artery

“…Most recently, a retrospective multicenter study reported findings comparing EVT and BMM with or without thrombolysis in patients with peripheral PCAO, i.e., P2–P4 segments, hence after exclusion of P1 occlusions ( 13 ). Consistent with the more peripheral location, the median NIHSS of five was even lower than in the present study and the aforementioned by Strambo et al ( 14 ).…”

“…The primary efficacy endpoint was early neurological improvement (ENI) defined as a decrease in four or more points compared to baseline NIHSS or zero points on the earliest NIHSS score after 24 h but before discharge in accordance with a recently published study ( 13 ). The secondary endpoint was good outcome, defined as mRS 0–2 after 90 days.…”

How to Improve the Management of Acute Ischemic Stroke by Modern Technologies, Artificial Intelligence, and New Treatment Methods

“…Medium vessel occlusions (MeVOs) defined as M2/3, A2/3, and P2/3 segment occlusions naturally represent the next frontier [92]. Compared with standard medical treatment with or without intravenous thrombolysis, mechanical thrombectomy for posterior circulation is also a safe and technically feasible treatment option for occlusions of the P2 or P3 segment of the posterior cerebral arteries if performed at comprehensive stroke centers [93].…”

Influence of intravenous alteplase on endovascular treatment decision-making in acute ischemic stroke due to primary medium-vessel occlusion: a case-based survey study

“…21 The same applies to the validity of the NIHSS in PCA strokes: P2/P3 occlusions often present with lower NIHSS scores, possibly because the NIHSS does not optimally reflect the typical posterior circulation stroke symptoms. 10 Therefore, we included detailed descriptions of the neurological loss of function for each case scenario, rather than only an NIHSS value (see online supplemental figures 1-3).…”

“…5 Given the overwhelming efficacy of EVT in LVO stroke 6 and encouraging preliminary safety and efficacy data in the MeVO patient population, 7 physicians are increasingly treating MeVO patients with EVT. [8][9][10] A well-designed clinical trial to evaluate EVT in MeVO stroke is needed, but a logistical concern for such a trial includes understanding which factors may influence clinical equipoise for EVT. In this case-based survey study, we aimed to measure the degree of influence prior intravenous alteplase treatment would have on physicians' EVT decision-making in MeVO stroke.…”