Footnotes

• X @josenalencar, @smithECGBlog

• Contributors JNdA, HPM, JTTM and SWS were involved in the study design, data acquisition and interpretation of results. All authors contributed equally to the planning, conduct and reporting of the work described in the article. They were also involved in drafting and critically reviewing the manuscript. All authors approved the final version. JNdA, HPM, JTTM and SWS share the responsibility as guarantors of this manuscript.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

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