Introduction: Contraindications for intravenous thrombolysis are not infrequent (eg. anticoagulation, recent surgery, unclear last known well). With overwhelming recent evidence supporting the use of endovascular thrombectomy for large-vessel occlusive stroke, we conducted a metaanalysis to compare long-term functional outcome between thrombectomy-alone versus combined IV-tPA and thrombectomy.
Hypothesis: Patients with acute ischemic stroke ineligible for IV-tPA treated with thrombectomy-alone have equally favorable long-term functional outcomes to patients treated with combined IV-tPA and thrombectomy
Methods: Searched PubMed from 2014-2016 using pre-specified terms for studies that report odds ratio of improvement in mRS score at 90 days comparing thrombectomy vs IV-tPA stratified by whether patients had received IV-tPA. Multivariate adjusted odds ratios were used for the metaanalysis. Pooled odds ratio estimates across trials were synthesized by using a random-effects model based on Mantel-Haenszel methods. The pooled estimates were compared between thrombectomy-alone and combined IV-tPA and thrombectomy. Forest plots constructed.
Results: Of the 920 studies, 3 studies reported subgroup analysis with 822 participants, 19.5% (N=160) received thrombectomy-alone, 80.5% (N=662) received combined IV-tPA and thrombectomy. Among patients who received thrombectomy-alone, the pooled odds ratio of good functional outcome at 3 months was 2.48 (1.43-4.30), in the combined IV-tPA and thrombectomy group the pooled odds ratio was 1.85 (1.37-2.49).
Conclusions: Endovascular therapy was an effective therapy for patients ineligible for IV-tPA presenting with acute ischemic stroke caused by large vessel occlusive disease. While IV-tPA should not be withheld before thrombectomy in IV-tPA eligible patients, prospective studies are needed to select those who may benefit more from thrombectomy-only treatment.