Inventing and improving pace makers - from Sydney to the world (guest post)

As the body’s primary device for pumping blood over the body, the heart was seen as the most critical organ (after the brain), protect­ed by the rib cage. But even healthy bodies were vulnerable to dis­eases and de­f­ects. Aptly Dutch doc­tor-physiologist Willem Einthoven won the 1924 Nobel Prize in Med­ic­ine for electro­cardiog­raphy.

British-born Mark Lidwill (1878-1968) emigrated with his parents to Aust­ralia in 1894. Lidwill studied medicine at Melb­ourne Uni, grad­uat­ing with honours (1902) and a Doct­or­ate in Med­ic­ine (1905). He in­v­ented unique medical tools & methods, including successfully desig­ning & manufacturing the Lid­will Intra-Tracheal Anaes­thetic Machine (1910), used in Austral­ian operating theatres for 3 decades.

Dr Lidwill designed and patented the Lidwill Anaesthetic machine

Crown St Women's Hospital, Sydney 

now closed  

He moved to Sydney in 1913, becoming an anaesth­et­ics lecturer at Roy­al Prince Alfred Hospital. In 1926 he worked in an­aesth­etics & cardiol­ogy with Sydney Uni phys­ic­ist Edgar Booth at Crown St Women's Hospital, inventing a portable machine for mechanical or insufflation anaesthesia. Dr Lid­will succ­ess­fully re­vived a still­born baby using el­ectrical stim­ul­ation to the heart i.e he pl­aced a needle directly into the baby’s heart, admin­ist­ering 16-volt impulses.

His invention, cardiac pacemaker, has saved many lives and was named by Nat­ional Geographic as being a Top Australian Invention That Chang­ed the World. In order to avoid public con­troversy, Dr Lid­well unfortunately did NOT patent his invention, and he did NOT leave photos of the machine. But he did write a detailed report to 3rd Congress of the Australian Medical Society. 

Having heard of Dr Lid­well’s success, Dr Albert Hyman (1893-1972) wanted to develop a sim­ilar de­vice in NY­. Hyman learned how to revive a stopped heart with intra-cardiac ther­apy. His plan was to inject drugs like epin­ephrine that caused the heart to move again, but real­is­ed that it was the physical act of inserting the needle that caused card­iac wall action. In 1932, this cardiol­ogist resus­cit­ated some pat­ients using periodic voltage impulses. He built an electro­-mechanical device and then pace­maker-powered by a hand-cranked motor.

Hyman's processes did not win general accept­ance from U.S’s med­ic­al community that wasn’t ready to embrace cardiac electro-stimulat­ion. Their opposit­ion later caused him to turn to the US Navy in WW2, to use his device on military pers­on­nel dying in tents. Fortunately his vision evolved, with fur­ther expert work in Sweden etc.

In the 1950s scientists met the chall­enge of correcting the irreg­ular beats caused by the heart’s natural pacemaker, the sinus node. And the advent of modern advance­ments led scientists and the medical society to imp­rove the qual­ity of pacemakers! The invent­ion of silicon transistors and smal­l­er batteries helped with portability.

In 1951, Canadian electrical engineer John Hopps of the National Re­search Council of Canada/NRC created the first external portable pace­maker that needed to be plugged into power points. Then Toronto Uni’s Wilfred Bigelow and John Call­aghan, together with John Hopps, jointly published their work on heart stimulation.

In 1952 Boston cardiologist Dr Paul Zoll made the first practical ext­er­nal pace­maker. He used the basic circuitry from Canada’s NRC mach­ine, but instead of having the electrodes attached to the heart it­self, the electrodes were att­ached to the patient’s chest. This device wasn’t suitable for long-term use be­cause 1] it could only be used while the patient was in hosp­it­al and 2] electric shocks to the chest skin involved pain. But the pacemaker got better with micro-tech­nology, crediting Zoll as one of the forefathers of modern cl­in­ical cardiac pacing.

In 1957 scientist Earl Bakken, in response to American heart sur­g­eon Dr Wal­ton Lillehei, developed the first wearable transist­or­ised pace­maker in Minneapolis. This pro­totype was meant for labor­atory use, but Lil­lehei liked it so much he used it on various patients. In 1958, promp­t­ed by Swedish Dr Åke Sennings, Dr Rune Elmqvist designed the first re­charg­eable, implantable pacemaker. Dr Senning implanted myocardial elect­rodes and a pulse generator with a rechar­geable nickel-cadmium batt­ery. The first fully implanted pacemaker was succ­essfully inst­al­led in 1958. But it was not until later that long-life lith­ium bat­teries developed by Wilson Great­bach maximised pacemakers’ longevity.

Dr Lillehei examined a young patient wearing an external pacemaker
of the type invented by Earl Bakken, 1961.
Saturday Evening Post

Trans-venous catheter pacing was introduced by Dr Seymour Furman in Montefiore Medical Centre in the Bronx in 1958. Here the electrode was passed down a vein to the interior of the heart, permitting the development of intra­cardiac diagnosis of ar­rythmias/abnormal heart rhythms. But fully implantable pace makers were impossible until the sil­icon transistor was develop­ed. In 3 years of that first implant, a pulse generat­or attached to epicar­dial leads was implanted at Royal Melbourne Hosp­it­al. An eng­ineer, with intermittent comp­lete heart block, rec­eiv­ed epicardial leads and an external pulse generat­or. He proposed a simple sensing circuit, designing the first demand pacing system.

By the mid 1960s, physic­ians were in­sert­ing trans-venous leads in the right ven­tricle att­ached to pulse generators implanted in the anterior abdominal wall. An Australian pacemaker company founded in Sydney, Telectron­ics, designed many of the feat­ures of trans-venous leads and pulse generators we now have.

pacemaker before insertion, 2014

Universities Australia

Posteroanterior chest radiograph of a pacemaker 

with normally located leads in the right atrium.

By 1969 the lithium battery-powered device sensed heart rhythms and generated beats accordingly, so it was classified as a demand-pace­maker. But there was a technological challenge; this pacemaker could not activate the heart’s upper chambers. Science re­spond­ed with developments that allowed pacemakers to restore function to the heart’s lower chambers.

From 1970 on, the electron­ics industry replaced merc­ury batteries with lithium-iodine ones & silic­one rubber enclosed crucial pace­maker components. Pace­makers gained prog­ram­mable use, allowing doc­tors to adjust the device to the patient’s clinical needs. Read the Pace Maker Evolution.

Sydney’s Mark Cowley Lidwill Foundation was established in 2007, to promote and support the world-leading scient­if­ic research in cardiac electro­-phys­iology. Thank you Sydney, my alma mater.

Guest blogger: Dr Joe