St. Helena Hospital has agreed to pay $2.25 million to settle government claims that it performed unnecessary cardiac operations and overcharged Medicare, conduct that was revealed by a whistle-blowing hospital employee. The lawsuit accused the hospital of charging Medicare for medically unnecessary angioplasty operations, which clear blocked coronary arteries, between January 2008 and July 2011. The suit also said the hospital needlessly admitted angioplasty patients for resident care rather than treating them as outpatients, at lower cost. Under a federal law allowing private citizens to go to court on behalf of the United States, Carroll will receive $450,000 of the settlement and the rest will go to the government. In a statement, the hospital said it had cooperated fully with the federal investigation and noted that the settlement does not include any admission of wrongdoing.