Mechanical Thrombectomy in Isolated Occlusion of the Proximal Posterior Cerebral Artery

Abstract

Introduction: Endovascular therapy (EVT) is established as first-line treatment for acute ischemic stroke (AIS) due to large vessel occlusion (LVO) in the anterior circulation. For basilar artery occlusion, recent randomized clinical trials demonstrated not only equipoise but also advantages for EVT under particular circumstances. It remains unclear whether EVT offers an advantage over best medical management (BMM) including thrombolysis (IVT) in isolated occlusion of the proximal posterior cerebral artery (PCAO). Methods: Patients with AIS due to PCAO proven by CT or MR angiography were retrospectively identified from local databases at four comprehensive stroke centers in Germany, USA, and Taiwan between 2012 and 2020. Demographic and clinical data were collected, and imaging characteristics including pretherapeutic, interventional, and follow-up imaging were reviewed locally at each center. Patients were grouped according to therapy, i.e., BMM including IVT alone vs. BMM and EVT. Efficacy endpoints were early neurological improvement (ENI) after 24 h or at discharge, good outcome (modified Rankin scale 0-2) after 3 months, as well as hemorrhagic complications and in-house deaths as safety endpoints. Results: We included 130 patients of whom 23 (17.7%) received EVT. EVT patients had more proximal occlusions (69.9 vs. 43%, p = 0.023) and had a better premorbid function [premorbid mRS, 0 (0-4) vs. 1 (0-3), p < 0.01] when compared to BMM patients. IVT showed a trend toward being less performed in the EVT group (21.7 vs. 41.1%, p = 0.1), while other baseline parameters were balanced. Successful reperfusion was achieved in 52% of EVT patients. ENI was more frequent in the EVT group (61 vs. 35.5%, p = 0.034). Good outcome at 90 days and safety endpoints did not differ. In a bivariate analysis, ENI was independently predicted by the use of EVT (OR, 2.76; CI, 1.055-7.04) and the baseline National Institutes of Health Stroke Scale (NIHSS) (OR, 1.082; CI, 1.027-1.141 per point increase). Discussion: EVT in isolated PCAO appears safe and feasible. Positive effects on clinical outcome are primarily on ENI but also depend on the initial stroke severity. Further prospective or randomized studies are needed to better describe the potential long-term clinical benefits of EVT for PCAO as compared with best medical management.

Keywords: best medical management; endovascular therapy; mechanical thrombectomy; posterior cerebral artery; posterior circulation stroke.

Conflict of interest statement

CH is a consultant for Brainomix. TN received research support from Medtronic, SVIN. DK received a grant from Else Kröner-Fresenius Center for Digital Health. MM is a consultant for Medtronic, MicroVention, Stryker Neurovascular, phenox (money paid to the institution); has grants/grants pending from Balt, MicroVention (money paid to the institution); and received payment for lectures including service on speakers bureaus from Medtronic, MicroVention, Stryker Neurovascular. PR is a consultant for Boehringer and received lecture fees from Bayer, Boehringer Ingelheim, BMS, Daichii Sankyo, and Pfizer. SN is a consultant for Brainomix, Boehringer Ingelheim and received payment for lectures including service on speakers bureaus from Pfizer, Medtronic, and Bayer AG. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Copyright © 2021 Herweh, Abdalkader, Nguyen, Puetz, Schöne, Kaiser, Chen, Jeng, Möhlenbruch, Ringleb and Nagel.