Effect of atrial fibrillation on endovascular thrombectomy for acute ischemic stroke. A meta-analysis of individual patient data from six randomised trials: Results from the HERMES collaboration

J A Smaal; I R de Ridder; A Heshmatollah; W H van Zwam; Dwj Dippel; C B Majoie; S Brown; M Goyal; Bcv Campbell; K W Muir; A M Demchuck; A Davalos; T G Jovin; P J Mitchell; P White; J L Saver; M D Hill; Y B Roos; A van der Lugt; R J van Oostenbrugge; HERMES collaboration

doi:10.1177/2396987320923447

Effect of atrial fibrillation on endovascular thrombectomy for acute ischemic stroke. A meta-analysis of individual patient data from six randomised trials: Results from the HERMES collaboration

Eur Stroke J. 2020 Sep;5(3):245-251. doi: 10.1177/2396987320923447. Epub 2020 May 13.

Authors

J A Smaal¹, I R de Ridder¹, A Heshmatollah², W H van Zwam¹, Dwj Dippel², C B Majoie³, S Brown⁴, M Goyal⁵, Bcv Campbell⁶, K W Muir⁷, A M Demchuck⁸, A Davalos⁹, T G Jovin¹⁰, P J Mitchell¹¹, P White¹², J L Saver¹³, M D Hill⁸, Y B Roos¹³, A van der Lugt¹⁴, R J van Oostenbrugge¹; HERMES collaboration

Affiliations

¹ Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands.
² Department of Neurology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
³ Department of Radiology & Nuclear Medicine, Amsterdam University Medical Centers, location AMC, Amsterdam, the Netherlands.
⁴ Altair Biostatistics, St Louis Park, MN, USA.
⁵ Department of Radiology, University of Calgary, Foothills Hospital, Calgary, AB, Canada.
⁶ Department of Medicine and Neurology, Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia.
⁷ Institute of Neuroscience and Psychology, University of Glasgow, Queen Elizabeth University Hospital, Glasgow, UK.
⁸ Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Foothills Hospital, Calgary, AB, Canada.
⁹ Department of Neuroscience, University Autònoma de Barcelona, Spain.
¹⁰ Stroke Institute, Department of Neurology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
¹¹ Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia.
¹² Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK.
¹³ Department of Neurology, Amsterdam University Medical Centers, location AMC, Amsterdam, the Netherlands.
¹⁴ Department of Radiology and Nuclear Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands.

Abstract

Background: Atrial fibrillation is an important risk factor for ischemic stroke, and is associated with an increased risk of poor outcome after ischemic stroke. Endovascular thrombectomy is safe and effective in acute ischemic stroke patients with large vessel occlusion of the anterior circulation. This meta-analysis aims to investigate whether there is an interaction between atrial fibrillation and treatment effect of endovascular thrombectomy, and secondarily whether atrial fibrillation is associated with worse outcome in patients with ischemic stroke due to large vessel occlusion.

Methods: Individual patient data were from six of the recent randomised clinical trials (MR CLEAN, EXTEND-IA, REVASCAT, SWIFT PRIME, ESCAPE, PISTE) in which endovascular thrombectomy plus standard care was compared to standard care alone. Primary outcome measure was the shift on the modified Rankin scale (mRS) at 90 days. Secondary outcomes were functional independence (mRS 0-2) at 90 days, National Institutes of Health Stroke Scale score at 24 h, symptomatic intracranial hemorrhage and mortality at 90 days. The primary effect parameter was the adjusted common odds ratio, estimated with ordinal logistic regression (shift analysis); treatment effect modification of atrial fibrillation was assessed with a multiplicative interaction term.

Results: Among 1351 patients, 447 patients had atrial fibrillation, 224 of whom were treated with endovascular thrombectomy. We found no interaction of atrial fibrillation with treatment effect of endovascular thrombectomy for both primary (p-value for interaction: 0.58) and secondary outcomes. Regardless of treatment allocation, we found no difference in primary outcome (mRS at 90 days: aOR 1.11 (95% CI 0.89-1.38) and secondary outcomes between patients with and without atrial fibrillation.

Conclusion: We found no interaction of atrial fibrillation on treatment effect of endovascular thrombectomy, and no difference in outcome between large vessel occlusion stroke patients with and without atrial fibrillation.

Keywords: Ischemic stroke; atrial fibrillation; endovascular thrombectomy; large vessel occlusion.