A Navy jury listened for five hours yesterday as the former chief of heart surgery at Bethesda Naval Hospital was portrayed, in stunning contrast, as a surgeon troubled by flawed techniques and fading eyesight who killed unsuspecting retirees and as an experienced doctor who "did the best he could" for the sick.

Defense and prosecution attorneys presented opening arguments in what is expected to be weeks of testimony in the court-martial of Cmdr. Donal Billig. He is charged with the involuntary manslaughter of five patients at Bethesda and 24 counts of dereliction of duty for operating without proper supervision from June through September 1983.

Billig, 54, was commissioned by the Navy in December 1982 and stationed at Bethesda from January 1983 until November 1984, when questions were raised about his competence. Yesterday one of the prosecutors, Marine Col. Gerald L. Miller, said Navy officials' concern over Billig followed a pattern he had established throughout his career.

Billig had a history of problems at civilian institutions where he worked, suffered from near-blindness in his right eye since 1980 and lied about his past to join the staff at Bethesda, Miller said. The five people who died at Bethesda after operations by Billig -- retired Army Maj. William Franklin Grubb, retired Navy Petty Officer Joe B. Estep, retired Air Force Lt. Harold Coplan, retired Air Force Lt. Col. John L. Kas, and Lois Parent, wife of retired Marine Sgt. Maurice Parent -- "were unsuspecting victims," Miller said.

"They came to him for help of the most critical kind. None of them should have died," he said. "The accused wrongfully killed because of bad eyesight, bad judgment, poor surgical techniques and the inability to recognize his limitations."

In one case, Kas' operation in October 1984, Billig's techniques left the patient's "heart and chest so swollen that his chest could not be closed. He was taken out of the operating room bleeding," Miller said. Hours later, Kas was dead.

Defense attorney Denver Graham responded with a three-hour argument in which he told the court-martial panel that his client was truthful during his recruitment and during his tenure at Bethesda.

Graham later described Billig as an "excellent" chest surgeon who wanted to do good for the Navy in a specialty for which it clearly needed doctors.

When Bethesda officials wanted a heart surgeon, Billig said he would need retraining in order to perform the complicated procedures.

He underwent a retraining period but was pushed early in his duty to work "night and day" for a hospital that was understaffed in cardiothoracic surgeons, Graham said.

For each of the five involuntary manslaughter charges, Graham defended his client's action as proper surgical procedures undertaken in stressful circumstances.

"A doctor has to use his best judgment when he's in there looking at a living, beating heart . . . maybe my client selected the wrong way, but he selected a way that is an accepted standard," Graham said.

Billig discussed past professional problems he had with his Navy recruiter, Graham said, and when questions about his eyesight arose during a preliminary examination in September 1982, Billig traveled with the recruiter to undergo an eye exam at Bethesda Naval Hospital.

Navy documents from that exam found Billig fit for duty, although it was noted that he had suffered "trauma to the right eye." Subsequent exams by the Navy during the recent court-martial investigation, however, showed his sight in the right eye to be limited to 20/400. According to doctors, that rating is considered legally blind.

Graham said the Navy based its approval of Billig on the first Navy exam which "showed not that he was blind, as you've been led to believe, but that he had some diminished vision, something that he has never denied . . . . If someone fouled up in the ascension of Dr. Billig, it's not as a result of Dr. Billig's fraud or deceit."

Graham agreed that Billig had his operating privileges revoked at Monmouth Medical Center in Long Branch, N.J., in 1981, but he asserted it was because of professional jealousy from other surgeons there. Billig, however, told Bethesda officials about those problems in 1983 when his ex-wife threatened him with blackmail, Graham said.