I'll just add that back in the 1980s Arthur Deming (the guy who created the Japanese quality "miracle") came out with a book that showed how to cut medical costs in 1/2. The two big items were tort reform - consider that every item in a hospital, and every component of that item, has a liability insurance load of about 30%. So a kidney machine, for instance, uses about one foot of clear vinyl tubing for the blood pump. It has to be discarded after use, mainly for liability reasons. That's exactly the same tubing you can buy at Ace Hardware for about $1 per foot today. But it's been sanitized, inspected, and packaged in a sterile pack. The hospital has to buy it from the kidney machine maker to avoid liability issues. That piece of tubing, back in 1979, cost $150 each. Of that, the maker of the tubing that the kidney machine buys it from has to include 30% for their liability cost, upping the cost to the kidney machine company. Then the kidney machine maker has to insure on that increased cost. So now their cost is up by about 69%. (This is an actual example I was involved with many year ago.)
Then the hospital is paying 30%. And the doctors and staff are paying 30%. (In the late 1980s I knew a heart surgeon who paid over 30% of his gross pay for liability insurance. He was the 2nd most popular one in Arizona at the time. Others may have paid somewhat less.) So the increased cost of everything is compounded over and over.
The second item was paperwork reform. At that time (and mostly still) each insurance company had different paperwork, none of it was electronic. This is the area that the ACA may actually help with - I don't know for sure.
Deming estimated that fixing each of these would reduce overall costs by about 30%, for a total savings of over 50%.
A very strong contributing item today, that is going to get worse before it gets better, is that the ACA has just dumped a huge new cash cow into the healthcare industry's lap, when it was already floating in cash. Someone I know just went to the HIMSS conference in Orlando. He said he'd never seen such a wealthy business crowd. The parking lot was loaded with Lamborghini, Mercedes, the occasional Bentley. These were not the owners, these were the IT heads! The whole industry has gradually evolved into one of those elite clubs where the money just flows without end, and all the vendors have to do is suck up he cash. There's almost no sense of cost limitation - except for lip service of course! These folks have successfully turned "rent-seeking" into an industry lifestyle.