Tinsley Randolph Harrison was one of the great teachers of medical students and a cardiologist of international fame. Son of Alabama physician William Groce Harrison, he was educated at the medical school at John Hopkins University, where he received his M.D. in 1922. His graduate training was at Johns Hopkins and the Peter Bent Brigham hospitals. Harrison served as chief resident in Medicine at Vanderbilt University Medical School, then studied in Vienna and in Freiburg and Breisgau, Germany.

As Assistant Professor of Medicine at Vanderbilt University Medical School from 1928 to 1932 and as Associate Professor from 1932 to 1941, Harrison was known for his outstanding scientific studies on cardiovascular physiology and disease. His book, entitled Failure of the Circulation, was a landmark in clarifying the mechanisms of the symptoms of heart failure. He was also a pioneer in clinical investigation.

Additionally, Harrison served as the first full-time professor and chair of departments of medicine at three schools: the new Bowman Gray at Winston-Salem, Southwestern Medical School at Dallas, and the Medical College of Alabama at Birmingham. Harrison was also the second Distinguished Physician in the United States Veterans' Administration, the winner of the Kober Medal, and the Billings Lecturer for the American Medical Association, among many other honors.