Funding for this research was provided by:
British Heart Foundation (RG/13/16/30528, PG/13/86/30546, FS/15/70/32044)
NIHR Posdoctoral Fellowship (2010–03–023)
Received: 9 June 2017
Accepted: 21 December 2017
First Online: 7 February 2018
Ethics approval and consent to participate
: Ethical approval was obtained from the National Research Ethics Service (NRES) Committee London. Participants provided informed written consent to the investigation.
: Not applicable.
: The authors declare that they have no conflict of interest.
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