By Judy Foreman, Globe Correspondent

There may be no sadder thing for a doctor than to have to stop seeing patients. But last fall, cardiologist Thomas Graboys, 61, reluctantly concluded that he had no other choice. He wrote his patients, explaining that, because of the worsening of his Parkinson’s disease, he was closing his practice at the Lown Cardiovascular Center, a private practice affiliated with Brigham and Women’s Hospital. He will continue his research role as President of the Lown Cardiovascular Research Foundation.

“It was a terribly difficult decision. I never imagined myself not seeing patients,” Graboys said softly, sitting recently in his Brookline office. A lean, athletic man, he used to move like a dancer –agile, quick, with seemingly endless energy. Now, Parkinson’s, a movement disorder caused by the loss of dopamine-producing cells in the brain, causes him to move more slowly and change position every few minutes. His voice is weak – “like the volume switch has been turned down,” as he put it. Worst of all are the moments when a thought simply vanishes in midspeech, a symptom typical of 20 to 30 percent of Parkinson’s patients. By the hundreds, Graboys’s patients have written him, trying to heal the doctor who healed them.

“I have never dealt with a doctor whose skills, honesty, and considerateness I have admired more than yours,” wrote Philip B. Heymann, a Harvard Law School professor.

“I hold you personally responsible for making it possible for me to complete my work of 23 years on the United States Constitution,” wrote George Billias, a retired Clark University historian in Worcester. Graboys grew up in Fall River and still knows some of the Portuguese he picked up from other children. His father, he said, was a “no-nonsense” kind of guy who made his four children justify everything they wanted to do or buy. His mother was a nurse during World War II, a fact that Graboys, joking, said must have created some kind of “neural impulses” that predisposed him toward medicine. Though his father and all his siblings were or are lawyers, Graboys announced that he wanted to be a doctor when he was five.

To fellow cardiologists, he is known for his conservative, low-intervention approach to cardiac care and his willingness to spend time with patients, a trait Graboys now values in his own doctors. To the world at large, he is best known as part of the “dream team” of cardiologists who correctly diagnosed the ultimately fatal heart problems of Celtics star Reggie Lewis, who died in 1993. The pictures on his walls tell the story of his life –the young man from Fall River who went to Cornell University, then New York Medical College, the young doctor who went to visit his nephew in the Peace Corps in Mauritania and stayed for two months, seeing 30 to 40 patients a day in a dirt-floored hut.

Dr. Graboy's Fact Sheet

Resume: A senior physician at Brigham and Women’s Hospital and associate clinical professor of medicine at Harvard Medical School, Graboys has a resume 24 pages long, filled with honors, appointments, and published papers.

Nobel: Graboys was among the team of doctors who won the Nobel Peace Prize in 1985 for their work with the International Physicians for the Prevention of Nuclear War.

Hobbies: Graboys ran two marathons and piloted glider planes and continues to do yoga, take spinning classes, and play the drums.

Fan club: Cindy Bremer Smiegal, now 43, says Graboys saved her life when she was 18 and nearly died from a heart problem. After her recovery, she baby-sat for Graboys’s girls and developed a crush on the handsome doctor. ‘’I remember when you picked me up for baby-sitting in your sports car and hoping all my friends saw me,” she wrote in October.