Footnotes

• Contributors Both authors have provided substantial contributions to the conception or design of the work, or the acquisition, analysis or interpretation of data; drafted the work or revising it critically for important intellectual content; given final approval of the version published; and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

• 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 MSB has received research grants from Sanofi and speaker fees from Boston Scientific.

• Patient consent Not required.

• Provenance and peer review Commissioned; internally peer reviewed.