This is for the declaration form:
http://www.caa.co.uk/docs/49/SRG_Med...ros-Nov_04.pdf
and this for the link for the section at the CAA which explains more about it.
http://www.caa.co.uk/default.aspx?ca...=90&pageid=873
And if you do have any medical conditions the link to the section at the DVLA where they get their requirements from
http://www.dvla.gov.uk/media/pdf/medical/aagv1.pdf
And it's likely that all GPs will have access to an ECG if it is actually required.
HTH! And happy flying