If you "only" have an MD, you can already do most administration jobs given you have healthcare/clinical experience. If you have an MD/MBA, that's more than qualified. Adding an MHA would not help for 99% of people out there. I'd focus on getting clinical experience first.
If your question was having an MD/MHA and was thinking about getting an elite MBA (H/S/P, Booth, Sloan, Columbia, etc), then the name recognition may help you given the prestige and connections for an large/academic healthcare system, and may make it easier for you to obtain an admin position early in your career. However, in most cases if you already have any advanced masters in healthcare/business, it really doesn't matter that much and experience trumps everything.