By the time of Congress's involvement, Shiavo's name was nearly a household name. There had been a series of cases involving the family that had gained national attention over the years, yet there were Congressmen giving speeches asserting positive diagnosis of Shiavo's condition (and were near to giving odds on her readiness to spring from the bed) who were unable to pronounce her name.
You would assume that a Congressman would take the time to evaluate a case to have a full understand of the situation, especially in the case of legislation that may raise serious constitutional questions. It would also be fair to assume that through said study (in this case, dozens of court cases, the 14 years of medical records and the numerous journalistic investigations) one would have come across the proper pronunciation of the name of the subject.
While that is not a damning evaluation of individual legislators' understanding, it does raise questions as to the forethought given to such a radical piece of legislation. If the Congress is going to craft legislation that raises so many questions regarding federalism, religion, privacy, custody and proper medial treatment, you would hope that your legislator would take the time to adequately familiarize himself with the relevant information.
That said, when such questionable legislation is created in the name of one individual, you should have the assurance that your Congressman knows the name the person for whom they are working.