Kings general manager Geoff Petrie said in a statement Monday that informing Hayes his deal had been voided was "one of the most heartbreaking moments of my professional or personal life." He said Hayes asked the team to refrain from any further comment.
The team announced last week that a heart exam on the new Kings big man showed an abnormality that would require further testing. That came days after the former Houston Rockets forward-center signed a contract with Sacramento.
Hayes, now 28, averaged 3.4 points and 4.7 rebounds in 17 minutes per game in six seasons with the Rockets. He attended Sacramento's media day Thursday and appeared fine, joking around with several teammates, but was held out of the team's preseason opener at Golden State on Saturday night.
Hayes' situation is the second time in the last week that a medical exam on an NBA player revealed cause for concern.
Boston Celtics forward Jeff Green will have surgery to repair an aortic aneurysm and will miss the entire season. Green was scheduled for an operation on Monday at the Cleveland Clinic. Doctors told him the operation "should completely repair Green's condition and that he can expect to resume his NBA career next season," the Celtics said in a news release Saturday.
An aortic aneurysm, which is more common in older people, is a ballooning of the wall of the aorta, the major artery that carries blood from the heart to the rest of the body. A person may show no symptoms from the aneurysm; but if it ruptures, it is likely to be fatal if not repaired immediately.
Specifics of Hayes' condition have not been released.
The Kings only announced last week that a stress echocardiogram test revealed an abnormality. A call and email seeking comment from Hayes' agent, Calvin Andrews, were not immediately returned.
Hayes' release leaves a void in Sacramento's starting lineup and opens the possibility of a return by Samuel Dalembert, a free agent center who played with the Kings last season. Dalembert averaged 5.1 points and 4.9 rebounds in 17 minutes per game last season.
Sacramento hosts its second and final preseason game Tuesday night against the Warriors. The Los Angeles Lakers visit Sacramento for the Kings' regular-season opener Dec. 26.