Who is the leading medical expert on the diagnosis and management of
cardiac sarcoidosis?

I am looking for an individual, ideally well published on the topic
and recognized  by peers as an authority.  The expert must be for
cardiac sarcoidosis (as compared with pulmonary sarcoidosis or
sarcoidosis in general).  I am not looking for listings of hospitals
that simply provide information on cardicac sarcoidosis on their
website.