WASHINGTON (CNN) - Paula Nowakowski, the chief of staff to House Minority Leader John Boehner, died Saturday, according to a statement from Boehner.
"It is with profound sadness and shock that I announce the passing of Paula Nowakowski, my longtime chief of staff, trusted aide, and friend, who died suddenly last night," Boehner said in the statement released Sunday.
Boehner spokeswoman Antonia Ferrier said Sunday that the 46-year-old Nowakowski had "an apparent heart attack."
In his statement Boehner wrote, "Words cannot adequately express the sorrow and disbelief I and every member of our team are grappling with today in the wake of this stunning news. We will remember Paula as she would want to be remembered - as a tireless worker, faithful friend, rabid Detroit sports fan, whip-smart strategist, warrior for freedom, and devoted Catholic who counted President Ronald Reagan and Pope John Paul II among her greatest heroes."
President Barack Obama called Boehner on Sunday to express his condolences, Ferrier said.
Minority Whip Eric Cantor, the number-two Republican in the House, said in a statement: "I will remember her strong belief in a balanced approach to governance, and her efforts as a consensus builder - which embodied the wishes and principles of our founders. Paula earned the respect of her peers - both staff and Members in both chambers - who will no doubt miss her counsel and guidance."
But it wasn't just Republicans who reacted to news of Nowakowski's death.
"The entire Capitol Hill community is shocked and saddened by the sudden passing of Paula Nowakowski," said House Speaker Nancy Pelosi.
"As Chief of Staff to Republican Leader John Boehner, Paula earned the respect not only of her Leadership and Conference, but all House Members on both sides of the aisle. She served Leader Boehner both in his current position as well as previously at the Committee on Education and the Workforce with great distinction," Pelosi said.
–CNN's Paul Steinhauser and Dana Bash contributed to this report.