This is a direct copy of what I have just read in WHICH magazine dated January 2015,
" Induction hobs aren't the only thing that can potentially cause problems with pacemakers. Many top- of-the- range cars now have keyless ignition which depends on radio communication between the fob and the car, and the radio waves can adversely affect pacemakers. If you use a pacemaker always check with the car manufacturer before you buy."
It's not just top-of-the-range vehicles, my son's Ford Fiesta has keyless ignition!