Footnotes

• Contributors JHvL: conception and design, acquisition of data, analysis and interpretation of data, drafting the article, critically revising the article, reviewed submitted version of manuscript, approved the final version of the manuscript. DV: conception and design, acquisition of data, critically revising the article, reviewed submitted version of manuscript and approved the final version of the manuscript. RD: statistical analysis, critically revising the article, reviewed submitted version of manuscript and approved the final version of the manuscript. RvdB, MPV, CJMK, H-JS, JdV and RHMAB: critically revising the article, reviewed submitted version of manuscript and approved the final version of the manuscript. KB, conception and design, critically revising the article, reviewed submitted version of manuscript and approved the final version of the manuscript. HDB, conception and design, analysis and interpretation of data, critically revising the article, reviewed submitted version of manuscript, approved the final version of the manuscript and study supervision.

• Funding One of the authors (CJMK) is supported by a clinical established investigator grant of the Dutch Heart Foundation (grant number 2012 T077), and an Aspasia grant from The Netherlands Organisation for Health Research and Development (ZonMw grant 015.008.048). Two authors (HDB and JdV) are consultants for Stryker Neurovascular.

• Competing interests None declared.

• Patient consent Not required.

• Ethics approval The Institutional Boards of the Academic Medical Center and Radboud University Medical Center.

• Provenance and peer review Not commissioned; externally peer reviewed.