LAS VEGAS — At the University Medical Center here, alarms were set off three years ago — kidney transplants were failing at unusually high rates, and some patients were even dying.

Federal regulators moved to shut down the kidney transplant program, but the proposed penalty brought a rebuke from Representative Shelley Berkley, Democrat of Nevada, who helped lead a successful effort to get the officials from Washington to back down.

In pleading for a reprieve, Ms. Berkley and other members of Nevada’s Congressional delegation said they were acting on behalf of the state’s families, citing dire health consequences if the program was halted. But the congresswoman’s efforts also benefited her husband, a physician whose nephrology practice directs medical services at the hospital’s kidney care department — an arrangement that expanded after her intervention and is now reflected in a $738,000-a-year contract with the hospital.

Ms. Berkley’s actions were among a series over the last five years in which she pushed legislation or twisted the arms of federal regulators to pursue an agenda that is aligned with the business interests of her husband, Dr. Larry Lehrner. In addition to the hospital contract, he operates a dozen dialysis centers in Nevada and has played a central role in an industry campaign to lobby members of Congress — including his wife — on behalf of kidney care providers.