Thrombectomy in Posterior Circulation Tandem Occlusions: Multicenter Comparative Analysis of Procedural Techniques and Predictors of Clinical Outcomes

Background Evidence on thrombectomy outcomes for posterior circulation tandem occlusions (TOs) is mostly from small single-center series. Purpose To evaluate thrombectomy outcomes in posterior circulation TOs. Materials and Methods Data from consecutive patients from 15 North American centers (February 2016 to October 2023) who underwent thrombectomy for posterior circulation TOs-defined as intracranial vertebral artery, basilar artery, or posterior cerebral artery occlusion with concurrent proximal extra- or intracranial vertebral artery stenosis or occlusion-were retrospectively analyzed. Baseline clinical, imaging, and procedural variables were summarized. Primary and clinical outcomes included successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score ≥ 2b), safety outcomes (symptomatic intracranial hemorrhage [sICH] and procedure-related complications), and 90-day functional outcome (modified Rankin Scale [mRS] score). Univariable and multivariable logistic regression was used to identify factors associated with favorable outcomes. Results Among 123 patients (median age, 63 years [IQR, 55-72 years]; 77 male patients), median National Institutes of Health Stroke Scale (NIHSS) score was 17 (IQR, 9-28). Intravenous thrombolytics were administered in 37 of 123 (30.1%) patients, and 97 of 123 (78.9%) underwent general anesthesia. Combined stent retriever and aspiration was the most common distal thrombectomy technique (45 of 123 [36.6%]), then aspiration (40 of 123 [32.5%]). Rescue stenting was required in 48 of 123 (39.0%) patients, more for proximal than distal lesions (44 of 123 [35.8%] vs nine of 123 [7.3%]; P = .01). Median puncture-to-reperfusion time (ie, from groin puncture to mTICI score ≥ 2b) was 50 minutes (IQR, 31-91 minutes). Successful reperfusion occurred in 108 of 122 (88.5%) patients, and sICH occurred in 11 of 123 (8.9%). At 90 days, 55 of 117 (47.0%) patients had a favorable outcome (mRS score of 0-3), and 37 of 117 (31.6%) had died. Distal-first strategy (ie, distal lesion thrombectomy first) was associated with shorter puncture-to-reperfusion time (P = .02) and lower incidence of sICH (P = .04); "dirty road" technique was associated with rescue stenting (P = .04). In multivariable analysis, hyperglycemia (P = .03), hypertension (P = .046), higher baseline mRS score (P = .008), and higher presentation NIHSS score (P = .03) predicted unfavorable functional outcome (mRS score of 4-6), whereas prestroke antithrombotic use (P = .006), monitored anesthesia care (P = .03), successful reperfusion (P = .02), and distal-first strategy (P = .01) predicted favorable functional outcome. Conclusion Thrombectomy for posterior circulation TOs was feasible and effective, with favorable outcomes associated with the distal-first strategy.