1958

First implanted pacemaker, with rechargeable nickel-cadmium battery, designed in Stockholm by Rune Elmqvist, and implanted in a pocket behind the abdominal muscles by Elmqvist and cardiologist Ake Senning. It used the silicon transistor, and lasted only eight hours; a second one implanted the next day only two days. The patient, Arne Larsson, survived without a pacemaker until November 1961, when he received a redesigned Elmqvist pacemaker. He was alive in 2000, then on his 26th pacemaker (Jeffrey, 90-92; Morris, loc 2942ff.). First successful implanted pacemaker was implanted on Feb 3, 1960 in Montevideo, Uruguay. The next one, in April 1960, was invented by Wilson Greatbatch, who (by mistake) invented an electrical circuit capable of delivering an electrical impulse at a fixed rate minute per minute. The pacemaker was sutured to the heart via open-heart surgery at Millard Hospital in Buffalo; it kept the patient, a 77-year-old man suffering from total heart block, alive for 18 months. Today the electrodes are connected to the heart through the veins (transvenous) in a simple procedure under local anesthesia. Among the problems with the early pacemakers: (1) they were unsophisticated devices that only emitted a preset pulse, so that hearted rate did not vary between rest and exercise. (2) It took no account of heart’s underlying rhythm, permitting the external pulse to compete with that of the sinoatrial node; (3) battery life , estimated by Greatbatch at five or more years, was at best 18 months. With the advent of lithium iodine batteries, pacemaker batteries became non-rechargeable, highly reliable, and lasted for years. A third major advance came with the development of rate-responsive pacemakers that made real time automatic adjustments of stimulation frequency (Arzua). Early pacemakers “were barely more than a battery and a timer. They did not have sensing capabilities; the pacing rate was fixed; and there was no communication with device for programming or diagnostic information retrieval. The first pacemaker invented by Greatbatch included only eight components” (DeForge, 41). Contemporary pacemakers include a sensing circuit, a logic circuit, and an output circuit, with the ability to communicate with a pacemaker programmer and a remote monitoring device. The logic circuit determines whether to deliver or inhibit an output pulse. If an output pulse is needed, the output circuit takes over and paces the heart (42).