No, it is not. The implementation of Form 8959 is confusing. The amount of additional Medicare tax that is due is shown on Line 62 of Form 1040. However, the amount of additional Medicare tax that was withheld is included with normal wage withholding on Line 64 of Form 1040. In essence, Line 62 shows how much more you owe; Line 64 includes how much extra you paid.
Print Form 8959 to see how the reconciliation works (Part V). This has nothing to do with AMT.