Guidant's stent business is being sold to Abbott Laboratories, which is paying $4 billion in cash and acquiring $1.4 billion worth of Boston Scientific stock. The FTC is requiring Abbott, whose participation helped alleviate antitrust concerns, to sell the stock within 30 months. Now on tap are some of the most daunting tasks ever faced in the device industry: The first-ever integration of two giant firms, and the placating of CDRH, which has had serious issues with both companies in the past year. Inability to pull off the latter could compromise the firm's ability to introduce new products.