Medical Pioneer. A cardiac surgeon, he performed the first American heart transplant, and invented several devices to improve the lives of patients with heart disease. Raised in New York City, his physician father encouraged him to pursue a medical career. He graduated from New York University in 1940, received his M.D. from Long Island College of Medicine in 1943, and originally trained in neurosurgery. After two years service as a battalion surgeon in the US Army, he took a cardiothoracic fellowship then practiced surgery at Montefiore Hospital, in the Bronx, from 1948 until 1955 when he moved to Brooklyn's Maimonides Medical Center. Over the years, he introduced a number of inventions, most of them developed in conjunction with his older brother Arthur, that prolonged and improved the lives of people with cardiac disease; he inserted the first implantable pacemaker in May of 1961, the initial intra-aortic balloon pump (IABP) in 1967, and the first left ventricular assist device (L-VAD) in 1972, the last-named, which has been used on about three million patients, allowing patients with severe chronic heart failure to leave the hospital. In 1966 Dr. Kantrowitz prepared to perform the first heart transplant, though legal problems relating to the definition of donor death delayed his efforts for more than a year; on December 6, 1967 at Maimonides, he performed the first heart transplant in the United States, Christiaan Barnard in South Africa having beaten him by three days, and while his infant patient lived but six hours, he had paved the way for a now common procedure. In 1970 Dr. Kantrowitz and his entire team moved to Detroit where he maintained his surgical practice at Sinai Hospital and was professor at Wayne State University. He received a lifetime achievement award from the American Society for Artificial Internal Organs in 2001 and though officially retired continued research into new cardiac assistance devices. He lived out his days in eastern Michigan and died of the effects of advanced age.