The ones making the real money in healthcare are the doctors and nurses, who have been very successful in restricting competition. Doctors and nurses in the USA (and to a lesser extent Canada) make far more money than they do almost anywhere else in the world (in either absolute or relative terms). Doctors have also been successful in preventing/avoiding tracking their results; some are much worse than others, but it is very tough to find out how good/bad they are.

Hospitals and clinics in some states have been very successful in reducing competition, to the extent that you often need permission from your competitors to open a new one. Hospitals have also avoided much scrutiny by avoiding cost-accounting, which is a very interesting tactic.

Pharmaceuticals and insurance companies are the bogey-men of the industry, but they're not as profitable as most imagine, and their high overheads are largely due to regulatory burden.