Local Intra-arterial Thrombolysis during Mechanical Thrombectomy for Refractory Large-Vessel Occlusion: Adjunctive Chemical Enhancer of Thrombectomy

Abstract

BACKGROUND AND PURPOSE: Data on adjunctive intra-arterial thrombolysis during mechanical thrombectomy for refractory thrombus are sparse. The aim of this study was to evaluate the efficacy and safety of local intra-arterial urokinase as an adjunct to mechanical thrombectomy for refractory large-vessel occlusion. MATERIALS AND METHODS:We retrospectively evaluated patients with acute ischemic stroke who underwent mechanical thrombectomy for anterior circulation large-vessel occlusion between January 2016 and December 2019. Patients were divided into 2 groups based on the use of intra-arterial urokinase as an adjunctive therapy during mechanical thrombectomy for refractory thrombus: the urokinase and nonurokinase groups. Herein, refractory thrombus was defined as the target occlusion with minimal reperfusion (TICI 0 or 1) despite .3 attempts with conventional mechanical thrombectomy. The baseline characteristics, procedural outcomes, and clinical outcome were compared between the 2 groups.RESULTS: One hundred fourteen cases of refractory thrombus were identified. A total of 45 and 69 patients were in the urokinase and the nonurokinase groups, respectively. The urokinase group compared with the nonurokinase group showed a higher rate of successful reperfusion (82.2% versus 63.8%, P ¼ .034), with lower procedural times (54 versus 69 minutes, P ¼ .137). The rates of good clinical outcome, distal embolism, and symptomatic intracranial hemorrhage were similar between the 2 groups. The use of intraarterial urokinase (OR ¼ 3.682; 95% CI, 1.156-11.730; P ¼ .027) was an independent predictor of successful reperfusion. CONCLUSIONS:The use of local intra-arterial urokinase as an adjunct to mechanical thrombectomy may be an effective and safe method that provides better recanalization than the conventional mechanical thrombectomy for refractory thrombus in patients with embolic large-vessel occlusion.

Mechanical thrombectomy with intra-arterial thrombolysis versus mechanical thrombectomy alone in patients with acute ischemic stroke: A systematic review and meta-analysis

“…A previous meta-analysis including 4581 patients by Chen et al 10 reported that IA treatment (thrombolytics or glycoprotein IIb/IIIa inhibitors) was associated with a higher rate of functional independence and another meta-analysis including 2797 patients by Kaesmacher et al 11 reported that IAT was not associated with higher rates of functional independence as an adjunct to MT. Inclusion of additional studies 5,[12][13][14][15][16][17] such as results from the randomized CHOICE 17 trial in our analysis increased the sample size (7572 patients) by almost 2-4 folds compared with the previous analyses by Chen et al 10 and Kaesmacher et al 11 Therefore, the precision of estimates of various outcomes was higher, and type 2 errors in comparisons were reduced. By increasing the design diversity among included studies, we also identified the prominent effect of design and quality of the studies on the association between IAT and functional independence at 90 days.…”

“…The quality of included observational studies 5,6,[12][13][14][15][16][20][21][22][25][26][27][28][29][30][31] was assessed by three independent reviewers (A.L., I.N.A., and D.K.) for risk of bias using the Newcastle-Ottawa Quality Scale (NOS) for Cohort Studies.…”

“…The median quality grade was 8, with 11 studies having a quality grade of 8 or greater for risk of bias using the NOS scoring system 5,6,[12][13][14][15][16]20,25,29,31 (see Supplemental Tables 3 and 4). There was an overall low risk of bias using Rob-2 assessment tool for the randomized controlled trial.…”

“…[7][8][9] There are two previous systematic reviews and meta-analyses by Chen et al 10 and Kaesmacher et al, 11 which have provided conflicting results. A more conclusive analysis may be possible with the availability of additional studies 5,[12][13][14][15][16][17] including results from the randomized Chemical Optimization of Cerebral Embolectomy (CHOICE) 17 clinical trial. We performed an updated systematic review of the literature to evaluate the effect of IAT as an adjunct to MT.…”