Valerie Plame Wilson told lawmakers, "I felt like I had been hit in the gut," when her husband handed her the newspaper article revealing her identity as a CIA operative in 2003.
"I immediately thought of my family's safety, the agents, the networks that I had worked with. And everything goes through your mind in an instant," Wilson testified Friday.
Once her name and identity "were carelessly and recklessly abused" by senior Bush administration officials, Wilson could no longer continue her job.
The 2003 leak triggered a federal investigation and led to former White House aide I. Lewis "Scooter" Libby being found guilty of four of five counts of perjury, lying to the FBI and obstructing an investigation into the leak of Wilson's identity.
Wilson also pointed blame to other top White House officials.
Top Bush adviser "Karl Rove clearly was involved in the leaking of my name," Plame said.
House Oversight and Government Reform Committee Chairman Henry Waxman, D-Calif., said that even though prosecutors brought no charges against anyone for actually leaking her name, questions remain about whether proper procedures regarding covert or secret operatives were followed.
"This was an extraordinarily serious breach of our national security," Waxman said.
Waxman said Wilson's classified work would not be discussed but she did work on the prevention of the development and use of weapons of mass destruction.
Wilson told lawmakers she worked in the Counterproliferation Division of the CIA, working in the agency's Langley, Va., headquarters and traveling overseas on secret missions.
Special Prosecutor Patrick Fitzgerald, who spent years investigating the leak, was not on the committee's witness list. Fitzgerald cited federal rules prohibiting such discussions.
Wilson told lawmakers she believed she was outed for "purely political reasons" in retaliation against her husband, former Ambassador Joseph Wilson, who criticized the Bush administration's prewar intelligence on Iraq.
Joseph Wilson has written a book and one by his wife is expected out soon. The pair is also suing Vice President Dick Cheney and others, claiming their constitutional rights were violated.
Waxman says he wants to know whether the White House appropriately safeguarded Plame's identity.
During the obstruction of justice and perjury trial former Cheney aide Libby, it was revealed that many in the Bush administration knew Wilson worked for the CIA, but not that it was classified.
Also scheduled to testify Friday were attorney Mark Zaid, who has represented whistle-blowers; attorney Victoria Toensing, a deputy assistant attorney general in the Reagan administration and former chief counsel for the Senate Intelligence Committee who said early on that no law was broken and has criticized the CIA's handling of the case; and J. William Leonard, security director of the National Archives, who was to discuss general procedures for handling sensitive information.
The Associated Press contributed to this report.