Good Clinical Outcome Decreases With Number of Retrieval Attempts in Stroke Thrombectomy: Beyond the First-Pass Effect

Abstract

Background and purpose: Endovascular therapy is the standard of care in the treatment of acute ischemic stroke due to large-vessel occlusion. Often, more than one retrieval attempt is needed to achieve reperfusion. We aimed to quantify the influence of endovascular therapy on clinical outcome depending on the number of retrievals needed for successful reperfusion in a large multi-center cohort.

Methods: For this observational cohort study, 2611 patients from the prospective German Stroke Registry included between June 2015 and April 2018 were analyzed. Patients who received endovascular therapy for acute anterior circulation stroke with known admission National Institutes of Health Stroke Scale score and Alberta Stroke Program Early CT Score, final Thrombolysis in Cerebral Infarction score, and number of retrievals were included. Successful reperfusion was defined as a Thrombolysis in Cerebral Infarction score of 2b or 3. The primary outcome was defined as functional independence (modified Rankin Scale score of 0-2) at day 90. Multivariate mixed-effects models were used to adjust for cluster effects of the participating centers and confounders.

Results: The inclusion criteria were met by 1225 patients. The odds of good clinical outcome decreased with every retrieval attempt required for successful reperfusion: the first retrieval had the highest odds of good clinical outcome (adjusted odds ratio, 6.45 [95% CI, 4.0-10.4]), followed by the second attempt (adjusted odds ratio, 4.56 [95% CI, 2.7-7.7]), and finally the third (adjusted odds ratio, 3.16 [95% CI, 1.8-5.6]).

Conclusions: Successful reperfusion within the first 3 retrieval attempts is associated with improved clinical outcome compared with patients without reperfusion. We conclude that at least 3 retrieval attempts should be performed in endovascular therapy of anterior circulation strokes. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03356392.

Keywords: cerebral infarction; ischemic stroke; reperfusion; standard of care; thrombectomy.

Conflict of interest statement

Dr Fiehler reports Unrelated—consultancy for Acandis, Boehringer Ingelheim, Cerenovus, Covidien, Evasc Neurovascular, MD-Clinicals, Medtronic, Medina, MicroVention, Penumbra, Route 92 Medical, Stryker, Transverse Medical; Grants/Grants Pending: MicroVention, Medtronic, Stryker, Cerenovus. CEO Eppdata. Dr Flottmann received personal fees from Eppdata GmbH outside the submitted work. Dr Maros reports funding from the German Federal Ministry for Economic Affairs and Energy within the scope of Zentrales Innovationsprogramm Mittelstand (ZF 4514602TS8) outside the submitted work and unrelated consultancy for Smart Reporting and Siemens Healthineers. Dr Mpotsaris reports personal fees from Stryker, personal fees from Phenox, and personal fees from Perflow outside the submitted work. Dr Nolte reports personal fees from Boehringer Ingelheim, Bristol-Myers Squibb, Pfizer Pharma, Abbott, and grants from DZHK (Deutsches Zentrum für Herz-Kreislaufforschung) outside the submitted work. Dr Thomalla reports Unrelated—consultancy for Acandis, Stryker; Payment for Lectures Including Service on Speakers Bureaus: Bayer, Bristol-Myers Squibb, Boehringer Ingelheim, Daiichi Sankyo; Personal fees from Portola and Biogen outside the submitted work. The other authors report no conflicts.

Figures

Figure 1.

Association of the number of retrieval attempts with good clinical outcome (modified Rankin Scale score at 90 d [mRS90] ≤2) and successful reperfusion (Thrombolysis in Cerebral Infarction [TICI] score of 2b/3).A, Cumulative proportion of good clinical outcome and successful reperfusion by the number of retrieval attempts needed to achieve successful reperfusion. B, Contribution of each successful retrieval attempt to the absolute proportion of patients with successful reperfusion (TICI score of 2b/3). C, Relative proportion of mRS90 by number of retrieval attempts needed to achieve successful reperfusion. D, Primary mixed-effects model-based estimates of averaged marginal probabilities of good clinical outcome (mRS score ≤2) with 95% CI across all participating centers with respect to number of retrievals required for successful reperfusion, adjusted for age, baseline National Institutes of Health Stroke Scale score, and Alberta Stroke Program Early CT score. 0 denotes no successful reperfusion achieved (TICI score of 0–2a); 6, aggregation of ≥6 attempts.

Figure 2.

Relative proportion of good clinical outcome (modified Rankin Scale [mRS] score at 90 0-2) by successful retrieval, stratified by quartiles of time from groin puncture to final Thrombolysis in Cerebral Infarction (TICI) score. Even after adjusting for time from groin puncture to final TICI score, up to 3 retrieval attempts were significantly associated with good clinical outcome in secondary multivariate analyses. 0 denotes no successful reperfusion achieved (TICI score of 0–2a); 6, aggregation of ≥6 attempts.