A woman treated for the "bends" after a scuba diving accident off Santa Catalina Island died in a Long Beach hospital, Los Angeles County sheriff's deputies said. Debra Cassel, 26, of Huntington Beach, had been diving with friends near Casino Point when the accident occurred, deputies said. She died at Long Beach Memorial Hospital after she was treated in a hyperbaric chamber for a condition known as the "bends," in which the pressure of deep water condenses nitrogen in the bloodstream and forms deadly air bubbles in the blood. The cause of her death was listed as cardiac arrest. Cassel and a friend, Markley Gordon, of Fullerton, were inspecting their boat's anchor chain, about 120 feet under water, authorities said. When Gordon began to ascend, he noticed Cassel sitting on the ocean floor. He tried to help her, but began blacking out, and lifeguards were called to pull the woman from the water.