Yevgeny Mravinsky, 84, who conducted the Leningrad Philharmonic Orchestra in the first overseas tour by a Soviet orchestra. The official Soviet news agency Tass said he had taken the orchestra to 25 countries in Europe, Asia and the Americas since 1946. It said his work was "an organic blend of classical neatness of rendition and subtle handling of details." Fifty years ago, Mravinsky befriended the Soviet composer Dmitri Shostakovich while they were preparing the premiere of the composer's Fifth Symphony. Tass said Mravinsky was also fond of the works of Beethoven, Tchaikovsky, Wagner, Bruckner and Stravinsky. Tass reported Wednesday that Mravinsky had suffered a heart attack but did not say where he had died.