While hospital administrators declined to comment, attorneys representing them described the Jan. 9 complaint as "full of hyperbole" in court documents.
Gruessner was suspended with pay in September and barred from entering the hospital without notifying security. He filed a lawsuit against the hospital in November to regain his job. In the suit, Gruessner alleges he was being punished for being critical of Dr. Steve Goldschmid, dean of the UA College of Medicine in Tucson.
According to court documents, the hospital said Gruessner was suspended for allegedly altering transplant records or telling others to alter them. But Gruessner said he asked the business manager for transplant services to change data in the computer system that was inaccurate and said hospital administrators needed to be informed of the inaccuracies. He said his suspension was given shortly after.
"In the rare circumstance that any changes to data are made, proper checks and balances are in place to protect the integrity of our data," UA Medical Center spokeswoman Katie Riley said.
Aside from the heart and lung transplant programs, UA Medical Center has also seen an intestinal transplant program, which Gruessner created, permanently close. The hospital also no longer offers a cell transplant program for people with acute pancreatitis.
Hospital officials say a need for more experienced surgeons is one of the reasons the transplant programs are on hold.
The Mayo Clinic in Scottsdale and St. Joseph's Hospital in Phoenix are currently the only other places in the state where patients can get those procedures done.
Since being hired in 2007 as head of surgery, Gruessner garnered mostly praise for reviving the department. He also recruited doctors for the UA's Level One Trauma Center, the only one in the region. Gruessner is credited with hiring four of the six physicians who led the treatment of victims in the 2011 Tucson shooting that injured former U.S. Rep. Gabrielle Giffords. Now, the hospital has already formed a search committee to look for a new head of surgery.
Dr. Richard Carmona, former U.S. Surgeon General and a distinguished professor of surgery at UA, was among those on a panel in 2010 who gave Gruessner a positive review. Carmona, who said he is not involved in the dispute between Gruessner and the administration, said there's no denying the influence Gruessner had.
"He brought in excellent, academically gifted professors to build transplant services and the whole department of surgery," Carmona said. "He made it better than the way he found it."