Boston Scientific Corp.'s Guidant unit hopes to end a criminal case accusing it of failing to properly disclose changes made to some implantable heart devices when it appears in court Wednesday.

Guidant pleaded guilty last spring, but U.S. District Judge Donovan Frank rejected the deal because it didn't call for probation. Instead, the company agreed to pay $296 million in fines and forfeiture fees in what prosecutors said was the largest criminal penalty against a medical device company.

Guidant is accused of falsely reporting a change it made to one device in 2002 and failing to report a change it made to another in 2005 — leaving doctors and patients unaware of potentially dangerous problems. The company pleaded guilty to two misdemeanors: submitting a false and misleading report to the Federal Drug Administration about one defibrillator model and failing to notify regulators about a safety correction to another line of devices.

In rejecting the deal, Frank asked for more information about the company's compliance programs and community service. His options Wednesday include approving the agreement, imposing a different fine or requiring more supervision of the company.

In a document filed last week, defense attorney Daniel Scott wrote that Guidant had improved its compliance policies since 2005 and upgraded them further after Indianapolis-based Guidant was acquired by Natick, Mass.-based Boston Scientific in 2006.