On the eve of the opening of American Ballet Theatre's four-week engagement at the Kennedy Center Opera House -- the troupe's first appearance anywhere under its new artistic director, Mikhail Baryshnikov -- the company last night dimissed "with deep regret" principal dancers Gelsey Kirkland and Patrick Bissell "for gross breach of contract."

The company also indicated that it will file "professional misconduct" charges with the American Guild of Musical Artists, the dancer's union.

A statement issued by Herman E. Krawitz, executive director of Ballet Theatre Foundation Inc., particularly cited the two dancers for their failure to appear for a dress rehearsal with orchestra at the Center yesterday. In fact, neither dancer had arrived in Washington.

Krawitz also stated that the pair had been "chronically late and chronically absent from rehearsals" during a 13-week preparatory period for the Washington run. "Their actions represent severe damage to the company, and while we regret their dismissal, we have no other choice," concluded the statement.

Bissell's agent, Isabelle Zakin of Dube Zakin Management Inc., said she was aware that Bissell had missed key rehearsals but believed as of 9 o'clock last night that "they're en route to Washington, or there now."

"I cannot understand why ABT would come down so hard on such a star," Zakin said.

Bissell and Kirkland were scheduled to dance together in "Pas d'Esclave" on tonight's opening program, as well as in other key roles throughout the run. oThe company has announced that Kirkland's role in "Les Rendezvous" tonight will be taken by Marianna Tcherkassky, and that "Pas d'Esclave" will be danced by Susan Jaffe (a corps de ballet dancer and a native Washingtonian) and Alexander Godunov. Replacement casting for the rest of them will be announced shortly.

The absence of Kirkland and Bissell from the Washington performances will leave ABT with only three male principal dancers and four female principals. lKirkland, 27, is widely regarded as one of the finest ballerinas America has produced, though she has a reputation for being personally erratic. Bissell, 22, joined ABT in 1977, and quickly rose to a position of eminence. Recently, the two dancers have been linked romantically.

Born in Bethlehem, Pa., to a theatrical family, Kirkland joined George Balanchine's New York City Ballet at 15 and was a principal dancer four years later, with both Balanchine and Jerome Robbins creating roles for her. yWhen Baryshnikov defected from the Soviet Union in 1974 and Joined Abt, Kirkland left NYCB to dance with him, at his invitation.

Kirkland's career, however, has been marked by ups and downs. Physical and nervous ailments led to her abandoning a role opposite Baryshnikov in the film "The Turning Point." After a brilliant comeback with ABT, she was pictured on a Time magazine cover in 1978 for a story entitled "U.S. Ballet Soars." She danced again with ABT for the 1978-79 season, but in January of this year said she was unable to agree with the company on roles, partners and performance schedules, and failed to sign a new contract. Then she rejoined the troupe for rehearsals this fall. According to ABT's statement last night, her dismissal was preceded by "a number of incidents and warnings." l

Bissell has been something of a prodigy too. Born in Swanton, Ohio, he was a scholarship student at Balanchine's School of American Ballet, auditioned for ABT, and was cast in a challenging lead role only three months after joining the troupe. His rise to principal rank has been exceptionally rapid.