James K. Kirklin (born 1947 in Rochester, Minnesota)is an American cardiac surgeon who has made important scientific and surgical contributions in the fields of heart transplantation and mechanical circulatory support devices to assist the pumping action of the heart. He is Professor of Surgery in the Division of Cardiothoracic Surgery, past Division Director of the Division of Cardiothoracic Surgery 2006-2016, Director of the James and John Kirklin Institute for Research in Surgical Outcomes (KIRSO),Co-Director of UAB Comprehensive Cardiovascular Center  and holds the John W. Kirklin Chair of Cardiovascular Surgery at the University of Alabama at Birmingham
Kirklin is the son of the late heart surgery pioneer John W. Kirklin. He graduated from Ohio State University in 1969, where he was an All-American diver. He received his MD from Harvard Medical School in 1973 as a member of the Alpha Omega Alpha academic honor society. He completed general and cardiothoracic surgery residencies at Massachusetts General Hospital in 1978 where he was Chief Resident, and pursued additional training at Boston Children's Hospital in 1979 and UAB School of Medicine, where he completed his training in 1981. He was appointed Assistant Professor of Surgery at UAB in 1981,Director of Cardiac Transplantation in 1986, Professor of Surgery in 1987, and in 2006 was named Director of the Division of Cardiothoracic Surgery. Kirklin's surgical expertise includes surgery for congenital heart disease, heart transplantation, and mechanical circulatory support pumps. In 2012, Kirklin and his colleagues developed the first Children's Hospital pediatric cardiac surgical unit in the state of Alabama. Kirklin and his colleagues at UAB pioneered the development of multi-institutional collaborative outcomes research in pediatric and adult heart transplantation and mechanical circulatory support. link title In 2007, he was the first surgeon to bridge an infant with failing single ventricular heart to successful heart transplantation with a longer term pediatric heart assist device called the Berlin Heart ventricular assist device.  In 2011, he was the first surgeon in North America to implant the HVAD continuous flow ventricular assist device in a pediatric patient.  This 9 year old girl was supported for 60 days and she then underwent successful cardiac transplantation.In 2014, Kirklin was the first surgeon in North America to implant the Eva Heart continuous flow ventricular assist device.[Cardiovascular Surgery, 137(1), e40-e42.F. Bennett Pearce, MD, James K. Kirklin, MD, William L. Holman, MD, Cindy s. Barrett, MD, Robb L. Romp, MD, and Yung R. Lau, MD, Birmingham, Ala. J Thorac Cardiovasc Surg 2009;137:e40-2]In 2015, Kirklin led the surgical team that implanted the Berlin Heart on the youngest baby (17 days old) to receive extended (greater than 1 month) mechanical circulatory support (136 days) before undergoing successful heart transplantation. 
Scientific Work Kirklin and his colleagues at UAB established the Cardiac Transplant Research Database in 1990, which generated the first multi-institutional collaborative research in heart transplantation, producing numerous seminal publications over a 20-year span. In 1993, Kirklin and his UAB research group initiated the Pediatric Heart Transplant Study Group, which continues to lead the field in multi-instuitional studies. Currently, Kirklin is Principal Investigator of the $15 million NIH-sponsored national Registry for Mechanically Assisted Circulatory Support (INTERMACS). Kirklin is past president of the International Society for Heart and Lung Transplantation (ISHLT). In April 2016, the University of Alabama established the James and John Kirklin Institute for Research in Surgical Outcomes (KIRSO).
Kirklin was first author of the textbook of Heart Transplantation and co-authored the fourth edition of the textbook of heart surgery, Cardiac Surgery.[Mario C. Deng, M.D. N Engl J Med, Vol. 347, No. 26 December 26, 2002. www.nejm.org] He served as Editor of the Journal of Heart and Lung Transplantation from 2000-2009 and he is principal editor of the ISHLT Monograph Series. In 2014 Kirklin was the first recipient of the ISHLT Distinguished Educator Award. He has authored over 500 scientific publications.