In order to improve on the technique, Green introduced himself to Julius H. Jacobson, who had newly arrived at the Mount Sinai Medical Center, and was the first American to publish about using a surgical microscope to anastomose the smallest blood vessels.

[15][3][16] In an excerpt from Green's "After 50 years, a personal reflection on the development of internal thoracic artery (ITA) grafting", he reported that, "Although the procedure had been prohibited at the New York University Hospital, David Tice, Director of Surgery at the affiliated New York Veterans Administration Hospital, invited me to do it there.

"[17][16] In 1968 Green was a spokesman for the research team at the New York University of Medicine at the annual Clinical Congress of American College of Surgeons, sharing the outcomes of 12 patients on whom he had performed the surgery.

[18][10] In 1971 he documented his research and work on "coronary artery bypass grafts for congestive heart failure; a report of experiences with 40 patients" in The Journal of Thoracic and Cardiovascular Surgery (supported in part by a grant from the National Heart and Lung Institutes of the National Institutes of Health), which was read at the 51st Annual Meeting of The American Association for Thoracic Surgery, in Atlanta, Georgia in April 1971.

[20] In 1973 Green spoke on the topic at the scientific sessions at the American Heart Association, Pennsylvania Affiliate.