Rio de Janiero  - Brazil's former first lady Ruth Correia Leite Cardoso died of a heart attack at the age of 77, Brazilian media said Wednesday.

The wife of former president Fernando Henrique Cardoso, who was in office from 1995 to 2003, died Tuesday at her house in Sao Paulo, media reports said, quoting family doctors.

Her death followed several heart examinations last week after she had suffered intense chest pains.

Born on September 19, 1930, the anthropologist had been a highly regarded intellectual, teaching at the University of Sao Paulo and at universities in Chile, France and the United States. She published several books.

Ruth Cardoso fought against social injustice in Brazilian society not only during her time as first lady, President Luiz Inacio Lula da Silva said.

Jose Serra, the governor of Sao Paulo province, ordered three days of mourning and her husband's Brazilian Social Democracy Party canceled Wednesday's festivities to commemorate the 20th anniversary of the party's foundation. (dpa)