Tommaso Padoa-Schioppa, architect of the euro; at 70

Mr. Padoa-Schioppa, who was economy minister under prime minister Romano Prodi, died Saturday night after suffering a heart attack during a dinner in Rome with friends, according to one of those present, his onetime deputy Vincenzo Visco.

His death stunned Italy’s political and business elite, who remembered him as a passionate promoter of the European project and its single currency.

“He was among those who knew how to translate the European ideal into concrete and learned analyses and projects, giving in particular a lasting contribution to the birth of the euro and the euro zone,’’ said President Giorgio Napolitano of Italy.

During his seven-year term at the ECB, Mr. Padoa-Schioppa was one of the six members charged with guiding the euro through its first vital years after being introduced in 11 member nations on Jan. 1, 1999.

“He contributed decisively in the early years of the euro to the reputation of the ECB as a major actor in international and European cooperation,’’ said the Central Bank’s president, Jean-Claude Trichet. The euro zone, he said, “is losing a man of reflection, of action, and of vision, fully dedicated to European unity.’’

Prior his appointment to the ECB, Mr. Padoa-Schioppa held many prestigious posts in the Italian business and banking world. He first gained international recognition as the director general for economic and financial affairs at the European Commission from 1979 to 1983.

In 1993 he became deputy director general of Banca d’Italia. He surprised many in 1997 when he moved to Consob, Italy’s stock market watchdog. As chairman he fought to introduce reforms in the Italian stock market, particularly to clamp down on insider trading.

More recently, the Greek government tapped him to help deal with the country’s debt crisis and Fiat Industrial named him to the board just last week.

But it was his role in shepherding in the euro that made his mark.

Mr. Padoa-Schioppa was the executive board director with special responsibility for international relations, payment systems, and banking supervision. He traveled widely lecturing in important financial centers from New York to Tokyo and Beijing advocating the importance and potential of the euro.

An ardent supporter of the European project, the trilingual Mr. Padoa-Schioppa acknowledged the challenge that lack of political union presented to the euro. He repeatedly argued that “a strong currency requires a strong economy and a strong polity, not only a competent central bank.’’

With the euro well on its way, Prodi named Mr. Padoa-Schioppa economy minister after winning the 2006 elections and tasked him with the difficult job of trying to revive Italy’s zero-growth economy. It was a post he held until Prodi lost to Prime Minister Silvio Berlusconi in 2008.

Mr. Padoa-Schioppa, educated in Milan and Massachusetts, was married with three children.

Funeral arrangements were not immediately announced. Rome’s mayor offered city hall for the wake, noting that Mr. Padoa-Schioppa’s death was a loss for the entire nation.