I think this is a pretty, sophiticated, and in Italy, not so common name, in the US, a rare name. The pronunciation works well in both countries and it is very nice sounding.
Italian pronunciation:Dah-MYAH-Nah"A" as in "Father," in other words "Dah." Stress your "I" to "EE" and follow with another soft "A"-- MEE-AH-- blend and the result is "Myah." Finish with the final "A." [noted -ed]