Pacemaker

(1950) Invented by John “Jack” Hopps 1919

John “Jack” Hopps was born in 1919 in Winnipeg, After grad. degree in electrical eng. from the Unv of Manitoba in 1941, he was recruited to the Division of Radio and Electrical Engineering by the National Research Council, based in Ottawa. He would remain there for the duration of his career, working on a variety of innovations in the new field of biomedical engineering. As the head of the medical engineering section, he led a team in the development of devices designed to improve the quality of life for those affected by blindness and muscular disabilities, and to advance the diagnostic uses of ultrasound. He also furthered cardiovascular research by inventing machines for respiration, cathoderay displays for cardiac operating rooms, cardio scopes for postoperative monitoring, heart rate monitors for sports medicine, and, of course, the cardiac pacemaker.

In Invention of the pacemaker

During the 1940s, Hopps studied the use of radiofrequency reheating for pasteurizing beer in Ottawa. Hopps was so dedicated to this project that he looked upon his assignment to the Banting Institute in Toronto in 1949 “as an annoying interruption to this vital task.” Little did he know that this assi signment would have groundbreaking implications for the lives of so many cardiac patients around the world. Hopps and others went on to develop a series of experiments to refine this process for pacemaker-induced cardiac stimulation. With the parameters derived from these initial experiments, Hopps returned to the National Research Council in 1950 to design and build the first pacemaker prototype.

Implantation of first pacemaker

Hopps’ early work eventually led to the development of the implantable pacemaker. With the advent of transistor circuitry, the original vacuum tubes were replaced by transistors, which allowed the pacemaker battery to become small enough for implanting in the body. The first implantable pacemaker was developed by engineer Rune Elmqvist. It consisted of two transistors and was assembled in a mold of an empty British Kiwi shoe polish tin. On 8 October 1958, it was implanted by surgeon Ake Senning into the chest of Arne Larsson, a 43-year-old man who suffered from complete heart block and Stokes-Adams attacks. Larsson’s first pacemaker failed within 3 hours of implantation and the second was no longer functional after 1 week. Larsson would eventually undergo a total of 26 pacemaker replacement procedures, until his death in 2001 from unrelated causes.

To be continued in Next Edition