display custom header mail index

[Damaru <damaru@xxxxxxxxxx>]

Hello mutt users,

is there some some way to display the value of a custom header field
of mails in the index mode?

I was looked for some solution not very unlike:

set index_format = " .. %<X-My-Hdr>  .. "

but i could not find any.

thanks in advance,
Damaru.