An obituary in Tuesday's editions of The Washington Post about Dr. Andrew G. Morrow, 60, the chief of surgery at the National Heart Institute, stated incorrectly that his death was due to a heart ailment. A spokesman for the Montgomery County police said Dr. Morrow shot himself at his home in Rockville Aug. 12 and that the death had been ruled a suicide.

Dr. Andrew G. Morrow, 60, the chief of surgery at the National Heart Institute since 1953 and a pioneer in the development of some techniques now widely used in heart surgery, died of a heart ailment Aug. 12 at his home in Rockville.

Dr. Morrow, who joined the staff of the institute in 1953, was an authority on prosthetic heart valves. In 1960, he performed the first successful operation to replace the mitral valve. Later in the 1960s, he developed what became known as the "Morrow operation," a means of relieving obstructions in the left ventricular valve. Blood leaving the heart flows through this valve.

In addition to his work at the National Heart Institute, Dr. Morrow taught at the Johns Hopkins University School of Medicine. At the heart institute, he helped teach more than 125 clinical associates in surgery.

He was active in a number of professional organizations, including the Society for Vascular Surgery, of which he was a past president; the American College of Surgeons, of which he was a fellow, a governor and a chairman of the postgraduate course in cardiac surgery, and the International Cardiovascular Society, of which he was a president. He was a member of the editorial board of The Journal of Cardiovascular Surgery and a consulting reviewer of the New England Journal of Medicine.

In 1962, he received the Arthur S. Flemming Award as one of the 10 outstanding persons in federal service. The award cited his "ability, which is unique among surgeons, to apply basic physiology principles to problems in experimental and clinical surgery."

In an interview in a National Institutes of Health publication in 1977, Dr. Morrow spoke of his work in these terms:

"The operating room is a very highly structured environment. Heart surgery can take from two to six hours, and there is no time for questions. One person is first in command, another is second, and so on. It is a military atmosphere. When things go awry, and they will, the man in charge must keep his cool. There is a chain of command. It has to be that way."

Dr. Morrow was born in Indianapolis and graduated from Wabash College in Crawfordsville, Ind. He earned his medical degree at Johns Hopkins in 1946 and also received his training in surgery there. He spent a year as senior registrar in thoracic surgery at the General Infirmary in Leeds, England, and then took up his appointment at the National Heart Institute.

In the early 1960s, he visited the Soviet Union as a member of a delegation of U.S. physicians organized under the cultural exchange program.

In addition to the Flemming Award, Dr. Morrow received the Meritorious Service Medal of the Public Health Service and decorations from Greece and the Soviet Union.

In private life, Dr. Morrow was a fisherman who specialized in bass. He was a founding member of the Bass Anglers Sportsmens Society, a member of the Florida and Georgia Bass Association, the International Game Fish Association, the Society for Preservation of Currituck Bank and the Piscatorial, Chirurgical and Imbibitorial Society of Currituck County Inc. He was a past president of the Montgomery Bass Anglers.

Survivors include his wife, Phyllis R., of Rockville; a son, Andrew G. Jr., of Gaithersburg; two daughters, Elizabeth Murtha, of Steamboat Springs, Colo., and Katherine G., of Rockville; two brothers, Richard R., of Indianapolis, and Dr. Dean H., of Houston, Tex.; a sister, Judith McGinnis, of Indianapolis, and two grandchildren.