Palmetto Health Greenville Health (copy)

Palmetto Health and Greenville Health System were renamed Prisma Health earlier this year. File/Provided

Mark Ohalla

Mark O'Halla has been named CEO of Prisma Health. Provided/Prisma Health

After an unusual move to name two chief executives, and after both said they would stand aside, the largest health care system in South Carolina has found a new leader.

Prisma Health on Thursday named a senior executive at a Michigan-based medical provider to replace Michael Riordan and Charles Beaman in the top job they'd been sharing.

Mark O'Halla has been executive vice president and chief operating officer of McLaren Health Care since 2014. Headquartered in Grand Blanc, northwest of Detroit, the system includes 14 hospitals, a slightly smaller network than the 18 medical centers that Prisma operates.

O'Halla has about 30 years of experience in health care management roles. He is expected to start his new job in mid-August.

"We believe his experience leading a multi-regional health care system will be a critical element in ensuring Prisma Health continues its journey to transform health care for our communities," James "Rick” Wheeler, chair of the Prisma board, said in a statement. 

O'Halla said in a statement he was looking forward to joining a "vibrant new health company, focused on providing exemplary quality, smart growth and sustained financial strength."

"I am also excited to work with physicians and university partners to advance its academic mission," O'Halla said.

Prisma has 32,000 employees, making it the largest health system employer in the state. By comparison, the Medical University of South Carolina employs about 13,000 workers.

Prisma reports caring for 1.2 million patients in South Carolina annually.

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The system was created when Upstate-based Greenville Health and Palmetto Health of Columbia consolidated in January. In an unusual arrangement, the CEOs of both organizations remained after the merger.

On Jan. 11 Prisma announced it was launching a national search for a new chief executive, with the goal of completing the process by the summer.

Riordan will step down Friday. Beaman will continue as CEO until O'Halla arrives this summer, Prisma said. The contracts for the two departing executives expire at the end of the year.

Their successor has as bachelor’s degree in accounting and Finance from the University of Toledo and a master’s degree in business administration from the University of Rochester.

O'Halla will live and work in Greenville, where Prisma has its executive offices.

Reach Mary Katherine Wildeman at 843-937-5594. Follow her on Twitter @mkwildeman.