Medicare beneficiaries who have been waiting months and even years for a hearing on their appeals for coverage may soon get a break as their cases take top priority in an effort to remedy a massive backlog. Nancy Griswold, the chief judge of the Office of Medicare Hearings and Appeals (OMHA), announced in a memo sent last month to more than 900 appellants and health-care associations that her office has a backlog of nearly 357,000 claims. In response, she said, the agency has suspended action on new requests for hearings filed by hospitals, doctors, nursing homes and other health-care providers, which make up nearly 90 percent of the cases.