The West German tabloid daily Bild said today it has acquired two recent film reels depicting Soviet dissident Andrei Sakharov to be in frail health and undergoing treatment for serious heart and circulatory problems.

The films, 75 minutes in length, would be the first tangible evidence produced in nearly a year of Sakharov's plight in Gorki, where he is being held in internal exile with his wife, Yelena Bonner.

In one sequence, shown in black and white, Sakharov is given a detailed medical examination, including a cardiogram test. His wife is also in the room. A neurologist later appears to check Sakharov's reflexes, tapping his forehead, cheeks and chin with a small hammer.

In the other reel, filmed in color, Sakharov's doctor presents a bleak medical report saying the physicist is "suffering from serious heart rhythm disturbances, narrowing of the arteries, atherosclerosis and the onset of Parkinson's disease."

The doctor, named as Natalya Yevdokimova, said Sakharov is receiving all necessary care and medication. Bild quoted her as saying that she has been treating him for four years and that his condition is satisfactory despite his various afflictions.

The color film reportedly shows that Sakharov was given a comfortable room at an unidentified clinic in or near Gorki. He can be seen receiving letters, including one from a nuclear research institute in Tokyo, and also eating, exercising and reading U.S. news magazines.

While the exact date of the film is uncertain, Sakharov is portrayed changing a calendar in his room with June 14 as the last visible day. The magazines carry the dates May 27 and June 3.

Last August, Bild obtained another film from what the newspaper called "a high-ranking, authorized Soviet informant who occasionally carries out Kremlin assignments to bring news to the West." Bild gave no details this time as to how it gained possession of the films.

The source, then and now, is believed to be Viktor Louis, a Soviet journalist with close contacts in the Communist Party hierarchy who has served in the past as a conduit of officially sanctioned material sold or given to western media.

Sakharov staged a hunger strike a year ago hoping to prod the government into allowing his wife to go to the West for medical treatment of a serious heart ailment. He reportedly was taken to a clinic and force-fed.

In the film, Dr. Yevdokimova denied recent reports that Sakharov has started another hunger strike. "Some people in the West say he is starving to death. That is an insult to our personal feelings and our professional abilities," she is quoted as saying.

Sakharov's wife, Bonner, was arrested in May l984 while trying to fly from Gorki to Moscow allegedly to seek political asylum at the U.S. Embassy.