Wiechart, 48, steps into the role after serving as VP and COO since 2009.
Slipkovich and Tom Anderson, vice chairman of the board, founded Capella in 2005 when they partnered with private equity firm GTCR to purchase four hospitals from Nashville-based hospital giant HCA.
GTCR was reported in September to be searching for potential buyers for the chain.
A news release said the transition would allow Slipkovich to focus more time on “strategic market development and growth” as well as investor and government relations.
Wiechart was a founding member of LifePoint Hospitals, a Brentwood, Tenn.-based chain, in 1999, where he served as senior vice president and group president. He also spent time at HCA, where he held CFO roles at a number of hospitals.
Slipkovich led Capella through rapid growth and development, including a joint venture last year with St. Thomas Health to operate four hospitals in Middle Tennessee. Capella's hospitals are also part of St. Thomas' accountable care organization, MissionPoint.
Capella has held a spot for two years in a row on Modern Healthcare's list of fastest-growing companies in the industry.
Slipkovich was on Modern Healthcare's list of 100 Most Powerful People in Healthcare in 2009.
Follow Beth Kutscher on Twitter: @MHbkutscher