Background Optimal technical approaches of large-vessel anterior circulation acute ischemic strokes with concomitant extracranial internal carotid artery tandem occlusions is controversial.

Purpose This systematic review and meta-analysis evaluates: the overall outcomes of patients with tandem occlusions treated with second-generation mechanical thrombectomy devices; differences in outcomes of extracranial versus intracranial first approaches; and differences in outcomes of extracranial stenting at time of procedure versus angioplasty alone.

Methods MEDLINE, EMBASE, and the Web of Science was searched through September 2017 for studies evaluating patients presenting with acute tandem occlusions of the extracranial ICA and intracranial ICA, and/or proximal MCA treated with second-generation mechanical thrombectomy devices. Outcomes were pooled across studies using the random-effects model and expressed as cumulative incidence (event rate) and 95% CI.

Results Thirty-three studies were included in analysis. Overall mRS≤0–2 at 90 days was 47% (95% CI 42% to 51%). No statistical difference was seen in 90-day mRS≤0–2 for patients treated with extracranial versus intracranial first approaches, 53% (95% CI 44% to 61%) vs 49% (95% CI 44% to 57%) (P=0.58). No statistical difference was seen in 90-day mRS≤0–2 for patients treated with extracranial stenting versus angioplasty alone, 49% (95% CI 42% to 56%) vs 49% (95% CI 33% to 65%) (P=0.39). No other statistical differences in outcome or safety were identified.

Conclusions Nearly half of all tandem occlusion patients treated with mechanical thrombectomy have good neurological outcomes. No statistical differences in outcome are identified between extracranial first versus intracranial first approaches, nor extracranial stenting versus angioplasty alone.