AUSTIN, Texas (AP) — Former U.S. Homeland Security Secretary Tom Ridge was in the early stages of recovery from a heart attack, his wife said Friday, a day after he underwent an emergency heart procedure.

The 72-year-old Ridge, a former two-term Republican Pennsylvania governor, remained hospitalized in critically stable condition in Austin, Texas, where he was attending a Republican Governors Association conference.

In a statement, Michele Ridge said it's going to be "day-to-day" for her husband.

"We all know what a fighter he is," she said. "We'd ask those of you who have been sending prayers to keep them coming."

Tom Ridge was at his hotel when he called for help Thursday morning. His wife said first responders worked "heroically" to get her husband to the trauma center at Dell Seton Medical Center at the University of Texas.

Ridge underwent a cardiac catheterization and was resting comfortably and responding to doctors, she said.

Ridge, a U.S. Army veteran of the Vietnam War, also was a county prosecutor and a six-term congressman from Erie, Pennsylvania, before being elected the state's governor in 1994.

Ridge was the nation's first homeland security secretary, serving under Republican President George W. Bush until February 2005. He left the governorship after the terrorist attacks of Sept. 11, 2001, to join the Bush administration.

Since leaving government, Ridge has headed Ridge Global, a firm that advises on cyber security, international security and risk management.

Ridge and his wife live in Bethesda, Maryland.