"Given the facts I now know, I apologize as the senior leader of the Department of Veterans Affairs," he said.
His remarks came as the White House confirmed it had called Shinseki to meet with President Obama later Friday morning to discuss the mismanagement within the VA's health system and discuss whether he was the right person to fix the problems.
"I can't explain the lack of integrity among some of the leaders in our healthcare facilities," he told the conference. "This is something I rarely encountered during 38 years in uniform."
Shinseki acknowledged his original assessment of the problems was wrong and that the secret waitlists kept by the Phoenix VA to mask the length of wait times for appointments were not isolated.
"I no longer believe it," he said. "It is systemic."