Oops. From CBO's letter:
Finally, you asked what the net deficit impact would be if certain provisions of PPACA and the Reconciliation Act that were estimated to generate net savings were eliminated—specifically, those which were originally estimated to generate a net reduction in mandatory outlays of $455 billion over the 2010–2019 period. The estimate of $455 billion mentioned in your letter represents the net effects of many provisions. Some of those provisions generated savings for Medicare, Medicaid, or the Children’s Health Insurance Program, and some generated costs. If those provisions were repealed, CBO estimates that there would be an increase in deficits similar to its original estimate of $455 billion in net savings over that period.