The Soviet Union denounced conductor Mstislav Rostropovich of Washington National Symphony Orchestra and his wife, soprano Galina Vishnevskaya, yesterday as "ideological degenerates" and stripped them of their citizenship.

The action bars the world-renowned artists from returning to their homeland, from which they have been absent on temporary visas since 1974.

Rostropovich, a virtuoso cellist, was accused with his wife of giving concerts in 1976-77 "whose income revenue went to help white (anti-Soviet) emigre organizations."

[The National Symphony's president, David Lloyd Kreeger, said he reached the Rostropoviches in Paris and they choose not to comment at this time. "The news is a profound shock and we are deeply disappointed for them" said Kreeger. The White House, which the couple last visited Feb. 26 for a piano recital by Valdimir Horowitz, had no comment.]

News of the Kremlin's action came just five days after the leadership stripped the citizenship of former general Pyotr Grigorenko, 70, the much-decorated hero of World War II who has been a persistent critic of Soviet policies. Grigorenko went to the United States in December for the announced purpose of prostate surgery.

Rostropovich was a staunch defender of Nobel Prize-winning novelist Alexander Solzhenitsyn when the exiled writer was being vilified by the Soviet leadership in 1970. He sheltered Solzhenitsyn in the Rostropovich country house outside Moscow and openly denounced those attacking the writer, who now lives in Vermont.

The visas for the Rostropoviches were due to expire March 25. When the artists left the Soviet Union in 1974, they said they intended to return. But on Feb. 7, while announcing a European tour for the National Symphony, Rostropovich said that it would be "very very difficult" to predict whether the Soviet authorities would extend his visa again. In 1974, he was granted a two-year extension, but could only get one-year extensions thereafter.

In 1975, Rostropovich wrote that "for my wife and me, being abroad is not an escape from Russia but the only way to realize our musical dreams by which we express our love for Russia and our great people."

Yesterday's announcement came on the first anniversary of the arrest of dissident Anatoly Schransky, whose trial on treason charges is thought to be imminent. At a news conference here, fellow dissidents announced that the 30-year-old computer expert has rejected the defense lawyer appointed for him by the authorities. The Soviet press has attempted to link Scharansky to the U.S. Central Intelligence Agency.

News of the action against the Rostropoviches came in a small article in Izvestia, the official government newspaper. The paper declared, under the headline "Ideological Degenerates":

"Having left several years ago on a foreign journey, Rostropovich and Vishnevskaya are showing no desire to return to the Soviet Union, have carried on unpatriotric activity and have besmirched the Soviet social system and the status of a citizen of the U.S.S.R. They systematically provided material assistance to subversive anti-Soviet centers and other foreign organizations hostile to the Soviet Union. In 1976-77, for example, they gave several concerts whose income revenue went to help white immigrant organizations.

"Formally remaining Soviet citizens, Rostropovich and Vishnevskaya in essence became ideological degenerates, carrying on activities directed against the Soviet Union and the Soviet people.

"Taking into consideration that Rostropovich and Vishnevskaya are systematically carrying out activities harmful to the prestige of the U.S.S.R. and incompatible with maintaining Soviet citizenship, the Presidium of the Supreme Soviet has resolved on the basis of Article Seven of Soviet law to deprive (them) of citizenship for activities besmirching the status of citizens of the U.S.S.R."

Rostropovich has long been a thorn in the side of the Kremlin, where political orthodoxy ranks well ahead of artistic freedoms. In recent years, this heavy-handed insistence on artistic conservatism and ideological silence has resulted in leading an extraordinary number of virtuosos from Soviet dance and music to seek fulfillment in the West. Such artists as Rudolph Nureyev, Mikhail Baryshnikov and Natalia Makarova have defected, bringing with them artistic impact that has profoundly changed Western ballet technique.

Rostropovich, 50, has had a similar impact on Western audiences in his dual roles as a stunning conductor and as a virtuoso of the fabled instrument of the late Pablo Casals. Rostropovich served as guest conductor of the National Symphony and became its musical director in 1977, succeeding Antal Dorati. Dorati had raised the orchestra from a level of competence to one of excellence.

An electrifying performer with interpretive skills at the podium equal to those of the world's finest conductors, Rostropovich set as his goal raising the National from excellence to brilliance.

In his first year, he was mildly criticized for setting forth a program that lacked excitement. Last month, he announced that the new season would include world premiers of compositions by Henri Dutilleux, Alan Hovhaness, Witold Lutoskawski, Andreas Makris and Gunther Schuller.

The Soviet action against the Rostropoviches came as another well-known Soviet artist, director Yuri Lyubimov of the famed Taganka Theater, is under attack by the Soviet press for remarks made last summer in Italy that have been seen as critical of the Soviet system.