WEBVTT - Electrocardiograms 0:00:01.320 --> 0:00:04.240 Welcome to Stuff You Missed in History Class, a production 0:00:04.400 --> 0:00:14.360 of iHeartRadio. Hello, and welcome to the podcast. I'm trace 0:00:14.400 --> 0:00:16.480 E V. Wilson, and I'm Holly Frye. 0:00:16.960 --> 0:00:19.680 I went to the doctor the other day. I think 0:00:19.720 --> 0:00:22.800 that's where I picked up the cold that I feel 0:00:22.840 --> 0:00:25.360 like is still present in my voice a little bit. 0:00:27.080 --> 0:00:29.400 Probably that's for sick people off and arm. 0:00:29.600 --> 0:00:32.240 No. I know I had a mask on the whole time, 0:00:32.320 --> 0:00:37.519 but you know, stuff happens while I was there. The 0:00:37.560 --> 0:00:41.440 doctor wanted to get an EKG, also called an ECG 0:00:41.920 --> 0:00:47.879 or electro cardiogram. People use those EKG and ECG abbreviations 0:00:47.880 --> 0:00:51.600 pretty much interchangeably. EKG is just the same word, but 0:00:51.840 --> 0:00:55.360 in German. While I was waiting for somebody to come 0:00:55.400 --> 0:00:58.320 back with the machine to do this test, I thought, 0:00:58.400 --> 0:01:01.640 what was this inventedrobably like the twenties or the thirties, 0:01:02.680 --> 0:01:04.679 And while waiting I looked it up on my phone 0:01:04.720 --> 0:01:08.280 and the answer was eighteen ninety five. Of course, that 0:01:08.319 --> 0:01:11.360 eighteen ninety five device looked a lot different from today's 0:01:11.480 --> 0:01:15.039 electro cardiographs, which is what the machine is called. And 0:01:15.080 --> 0:01:18.080 there are some other years on either side of eighteen 0:01:18.160 --> 0:01:22.679 ninety five, that you could also say was the first regardless, 0:01:22.680 --> 0:01:27.559 so that was earlier than I was expecting. So sitting 0:01:27.560 --> 0:01:29.640 there at the doctor's office, I dropped what I was 0:01:29.720 --> 0:01:33.040 working on for this show to do an electro cardiogram 0:01:33.080 --> 0:01:36.480 episode instead as a confession. I was also working on 0:01:36.520 --> 0:01:40.040 something that had turned out to be really unwieldy, and 0:01:40.120 --> 0:01:42.080 while I was in the waiting room, I had been 0:01:42.120 --> 0:01:44.679 sort of thinking through how in the world I was 0:01:44.760 --> 0:01:47.360 going to get this unwieldy thing done in time to 0:01:47.440 --> 0:01:50.320 record it. The unwieldy thing is still coming, it's just 0:01:50.360 --> 0:01:53.960 coming later. Also, my ECG was normal in case people 0:01:54.000 --> 0:01:58.600 are wondering, Like most of our episodes on medical developments, 0:01:58.640 --> 0:02:03.080 this does include some animal experimentation. Also, if you're a 0:02:03.120 --> 0:02:06.480 cardiologist or otherwise if you work with a lot of ECGs, 0:02:06.560 --> 0:02:09.519 I'll just go ahead and apologize. We're not going to 0:02:09.560 --> 0:02:13.040 talk in a lot of detail about what the actual 0:02:13.120 --> 0:02:18.000 readout means. I don't feel remotely qualified to get into that, 0:02:18.520 --> 0:02:21.280 and I also don't think are either muddling through it 0:02:21.400 --> 0:02:24.240 or just reading somebody else's definition word for word would 0:02:24.360 --> 0:02:28.000 actually add to the history of this in a way 0:02:28.000 --> 0:02:31.880 that would sort of add to it. For like typical 0:02:32.680 --> 0:02:38.440 non cardiologist, non physician type people. So the heart is 0:02:38.480 --> 0:02:42.440 a muscle and its beats are controlled by electrical activity 0:02:42.560 --> 0:02:46.160 generated in the sinus node also called the cinoaitrial node 0:02:46.560 --> 0:02:49.440 that's a part of the heart. An electric cardiogram is 0:02:49.480 --> 0:02:53.320 a non invasive test that measures this electrical activity using 0:02:53.360 --> 0:02:56.080 electrodes placed on the skin, which are connected to an 0:02:56.080 --> 0:03:02.080 electric cardiograph or ECG machine with leadwire. The machine translates 0:03:02.160 --> 0:03:05.520 those electrical signals into a graphical representation of a wave 0:03:05.880 --> 0:03:08.919 and that is immediately available to be read and interpreted. 0:03:08.960 --> 0:03:10.880 With today's technology. 0:03:10.800 --> 0:03:14.680 This is typically a fast, painless test, although people who 0:03:14.720 --> 0:03:18.000 are sensitive to adhesives or to the material the electrodes 0:03:18.040 --> 0:03:22.640 are made from can experience some irritation. That happened to 0:03:22.639 --> 0:03:24.760 me the first time I ever had one, yes, say 0:03:24.840 --> 0:03:27.919 something years ago, but not with this one most recently. 0:03:29.280 --> 0:03:33.040 This technology grew from both the study of electricity and 0:03:33.120 --> 0:03:35.920 the study of anatomy and physiology, and then all that, 0:03:36.040 --> 0:03:39.360 of course, started way before the end of the nineteenth 0:03:39.400 --> 0:03:43.600 century when the first ECGs were invented. People have been 0:03:43.760 --> 0:03:48.480 observing phenomena like static electricity and lightning since before the 0:03:48.480 --> 0:03:52.480 start of recorded history, and While different societies have had 0:03:52.520 --> 0:03:56.840 taboos around things like dissections and autopsies, people have also 0:03:56.960 --> 0:04:01.200 been doing them and examining hearts and other muscles for 0:04:01.320 --> 0:04:05.800 thousands of years. The word electricity was first used in 0:04:05.800 --> 0:04:09.160 writing by English polymath and member of Parliament Sir Thomas 0:04:09.200 --> 0:04:14.160 Brown in sixteen forty six in his Pseudodoxia Epidemica, or 0:04:14.360 --> 0:04:19.120 Enquiries into Very Many Received Tenets and Commonly Presumed Truths. 0:04:19.920 --> 0:04:21.680 This is a book that he wrote to try to 0:04:21.720 --> 0:04:26.920 correct an assortment of superstitions and commonly held misinformation. It's 0:04:26.960 --> 0:04:29.960 actually arranged into seven books, and as an example, the 0:04:30.080 --> 0:04:34.599 third book is devoted to dispelling misinformation about animals, including 0:04:34.640 --> 0:04:38.440 the idea that elephants don't have joints, that beavers escape 0:04:38.520 --> 0:04:42.320 hunters by biting off their testicles, although who could blame them, 0:04:42.400 --> 0:04:47.960 and that the ostrich digestith iron. Brown's descriptions of electricity 0:04:48.000 --> 0:04:52.120 are focused on static electricity, including the ability of materials 0:04:52.200 --> 0:04:56.400 like amber and jet to attract lightweight objects after being rubbed. 0:04:57.240 --> 0:05:01.039 Similar words like electric and electric were coined in the 0:05:01.080 --> 0:05:02.719 seventeenth century as well. 0:05:04.000 --> 0:05:06.880 I was extremely delighted by just the table of contents 0:05:07.000 --> 0:05:13.320 at this book. In the sixteen sixties, Dutch naturalist Yon 0:05:13.400 --> 0:05:18.600 Swammerdam carried out experiments on frogs and other animals. This 0:05:18.640 --> 0:05:23.200 included using his scalpel or another instrument to stimulate nerve 0:05:23.279 --> 0:05:27.520 tissue during dissections, and that would cause the corresponding muscles 0:05:27.520 --> 0:05:31.760 to twitch. He believed that these muscular contractions were caused 0:05:31.760 --> 0:05:36.839 by the flow of animal spirits or nervous fluid. There's 0:05:36.960 --> 0:05:41.120 some debate about whether these experiments involved electricity. Some of 0:05:41.160 --> 0:05:44.320 his instruments were made of multiple different metals, and they 0:05:44.360 --> 0:05:48.760 had voltage differences that could have produced a small current 0:05:49.560 --> 0:05:52.640 if that's the case, though he definitely was not aware 0:05:52.920 --> 0:05:54.320 that that was what was happening. 0:05:55.120 --> 0:05:58.760 About one hundred years later, researchers were studying animals like 0:05:58.880 --> 0:06:03.800 electric rays also called common torpedoes, as well as electric eels. 0:06:04.600 --> 0:06:08.719 One was American scientist and spy Edward Bancroft, who described 0:06:08.760 --> 0:06:11.760 torpedoes and their ability to shock people in his book 0:06:12.040 --> 0:06:15.960 An Essay on the Natural History of Guiana. His description 0:06:16.200 --> 0:06:20.000 didn't really line up with how people understood electrical charges. 0:06:20.040 --> 0:06:23.640 At this point, it was known that metal could conduct electricity, 0:06:23.680 --> 0:06:27.000 but that glass and sealing wax couldn't, and the idea 0:06:27.080 --> 0:06:30.400 of electricity coming from a living thing just seemed bizarre. 0:06:31.240 --> 0:06:34.560 Earlier descriptions of these animals had concluded that the jolts 0:06:34.560 --> 0:06:38.560 they produced were physical, not electrical, but Bancroft did some 0:06:38.640 --> 0:06:42.080 experiments showing that the shock from a torpedo was similar 0:06:42.120 --> 0:06:44.400 to the electrical charge that could be stored in a 0:06:44.480 --> 0:06:45.120 Leiden jar. 0:06:46.440 --> 0:06:50.800 In seventeen seventy two, British scientist John Walsh worked off 0:06:50.839 --> 0:06:55.679 of Bancroft's ideas to experiment with electric rays and found 0:06:55.680 --> 0:06:59.440 that it was possible to direct the shocks these rays 0:06:59.480 --> 0:07:03.839 produced through a circuit of four people. He wrote letters 0:07:03.839 --> 0:07:07.080 about this to Benjamin Franklin, and he was awarded the 0:07:07.200 --> 0:07:10.440 Royal Society's Coply Medal for his paper on the torpedo 0:07:10.640 --> 0:07:14.920 in seventeen seventy three. Then, in seventeen seventy five, Danish 0:07:14.960 --> 0:07:19.960 physician and veterinarian Peter Christian Ablegard used electrical shocks to 0:07:20.200 --> 0:07:25.160 quote render lifeless a bird and then to revive it. 0:07:25.160 --> 0:07:30.720 Italian researcher Luigi Galvani experimented with frogs, and on September twentieth, 0:07:30.760 --> 0:07:34.120 seventeen eighty six, he wrote, quote, I had dissected and 0:07:34.200 --> 0:07:37.000 prepared a frog in the usual way, and while I 0:07:37.120 --> 0:07:39.880 was attending to something else, I laid it on a 0:07:39.920 --> 0:07:43.760 table on which stood an electrical machine, at some distance 0:07:43.800 --> 0:07:48.800 from its conductor and separated from it by a considerable space. Now, 0:07:48.880 --> 0:07:53.239 when one of the persons present touched accidentally and lightly 0:07:53.560 --> 0:07:56.040 the inner cural nerves of the frog with the point 0:07:56.080 --> 0:07:58.800 of a scalpel, all the muscles of the legs seemed 0:07:58.800 --> 0:08:01.880 to contract again an again, as if they were affected 0:08:01.920 --> 0:08:07.800 by powerful cramps. Other eighteenth century researchers experimented with using 0:08:07.840 --> 0:08:12.760 electricity to revive the apparently dead, including English surgeon Charles 0:08:12.880 --> 0:08:17.560 Kite and Italian scientist Alessandro Volta. It's possible that these 0:08:17.600 --> 0:08:21.320 experiments were one of the inspirations for Mary Shelley's Frankenstein 0:08:21.720 --> 0:08:23.160 or the modern Prometheus. 0:08:24.080 --> 0:08:28.120 In the early nineteenth century, Johann Schwager of Nuremberg developed 0:08:28.160 --> 0:08:32.680 the first galvanometer that was an instrument to measure electrical current, 0:08:32.760 --> 0:08:37.080 which was later named in honor of Luigi Galvani. Around 0:08:37.120 --> 0:08:41.480 the same time, Danish physicist Hans Christian Ersted noted that 0:08:41.559 --> 0:08:44.800 it was possible for changes in electrical current to deflect 0:08:44.920 --> 0:08:49.960 a compass needle showing a connection between electricity and magnetism. 0:08:50.400 --> 0:08:54.280 By the eighteen thirties and forties, researchers were using galvanometers 0:08:54.280 --> 0:08:58.320 to study electrical activity in animals, not just ones that 0:08:58.360 --> 0:09:02.640 could produce an obvious chart like electric raisin eels. This 0:09:02.760 --> 0:09:07.880 included Italian physicist Leopoldo Nobili. In eighteen thirty four, he 0:09:08.040 --> 0:09:12.240 developed an instrument called an astatic galvanometer to detect very 0:09:12.280 --> 0:09:15.439 small electric currents, and he used it to detect a 0:09:15.520 --> 0:09:19.520 current between a frog's limbs and spinal cord. In eighteen 0:09:19.600 --> 0:09:24.480 forty two, Carlo Matiucci used Nobili's invention to detect electrical 0:09:24.559 --> 0:09:26.520 currents in the hearts of pigeons. 0:09:27.679 --> 0:09:31.640 Within a decade, researchers had started to realize a connection 0:09:31.800 --> 0:09:36.520 between the electrical activity of the heart and irregular heartbeats, 0:09:36.720 --> 0:09:42.480 specifically ventricular fibrillation. Maritz Haffe described this in eighteen fifty 0:09:42.640 --> 0:09:46.079 following experiments in the lab of his teacher Karl Ludwig, 0:09:46.600 --> 0:09:50.640 he was able to induce ventricular fibrillation in dogs by 0:09:50.640 --> 0:09:54.560 exposing their hearts to electrical currents. A few years later, 0:09:54.720 --> 0:09:58.600 in eighteen fifty six, Albert von Kolliger and Heinrich Mueller 0:09:59.240 --> 0:10:03.560 detected electionlectrical activity in frog hearts in a lab in Germany, 0:10:04.120 --> 0:10:08.200 discovering that the heart generated electricity and that there was 0:10:08.240 --> 0:10:11.480 a rhythm to it that was associated with each beat. 0:10:12.480 --> 0:10:16.960 Much of this animal research involved dissections or vivisections, and 0:10:17.080 --> 0:10:21.959 scientists were detecting electrical signals from exposed skeletal muscles and hearts. 0:10:22.520 --> 0:10:25.679 But by the late nineteenth century people started figuring out 0:10:25.679 --> 0:10:29.920 ways to record the heart's electrical activity from outside the body. 0:10:30.480 --> 0:10:32.960 We'll talk more about that after a sponsor break. 0:10:42.720 --> 0:10:47.599 In eighteen sixty nine, Scottish electrical engineer Alexander Muirhead was 0:10:47.679 --> 0:10:51.880 working at Saint Bartholomew's Hospital in London and he found 0:10:51.880 --> 0:10:55.199 a way to record the electrical rhythm of a patient's 0:10:55.280 --> 0:10:59.480 beating heart. He attached an electrode to the patient's wrist 0:10:59.600 --> 0:11:03.200 and the case connected that to a siphon recorder. This 0:11:03.360 --> 0:11:07.520 recorder was developed by William Thompson as a receiver for 0:11:07.600 --> 0:11:12.240 the extremely weak electrical signals that had traveled along underwater 0:11:12.360 --> 0:11:16.400 telegraph cables. That used a glass tube with an increas 0:11:16.440 --> 0:11:19.200 of war at one end, which swayed back and forth 0:11:19.280 --> 0:11:24.120 in response to positive and negative electrical signals. This created 0:11:24.160 --> 0:11:29.840 a continuous wavering line on a recording paper. For telegraph cables, 0:11:29.920 --> 0:11:34.480 that wavering line represented the dots and dashes of Morse code, 0:11:34.920 --> 0:11:38.040 but in muir head set up, it represented the electrical 0:11:38.120 --> 0:11:42.560 rhythm of the heart. This was most likely the first 0:11:42.679 --> 0:11:46.600 ever recording of electrical activity in the heart of a 0:11:46.760 --> 0:11:50.960 human patient, but Muirhead did not publicize this work. 0:11:51.760 --> 0:11:54.400 The next major step in the development of the electric 0:11:54.400 --> 0:11:59.120 cardiogram was the work of British physiologist Augustus Desiree Waller 0:11:59.200 --> 0:12:03.200 at Saint Mary's Hospital, London in eighteen eighty seven. He 0:12:03.320 --> 0:12:07.400 used a capillary electrometer developed by Gabriel Lippmann to record 0:12:07.440 --> 0:12:12.760 electrical activity from patient's hearts. This electrometer was made out 0:12:12.800 --> 0:12:16.720 of a glass tube filled with mercury. One end of 0:12:16.760 --> 0:12:20.400 the tube was formed into a tiny capillary that could 0:12:20.440 --> 0:12:25.320 be submerged in diluted sulfuric acid. There was an electrical 0:12:25.400 --> 0:12:29.280 potential difference between the mercury and the sulfuric acid, so 0:12:29.360 --> 0:12:32.320 when this setup was connected to the patient's body through 0:12:32.400 --> 0:12:37.040 electrodes and leads, the curved surface of the mercury in 0:12:37.120 --> 0:12:40.520 the tube or the meniscus would shift in response to 0:12:40.559 --> 0:12:45.280 the current from the patient's heart. These shifts were tiny, 0:12:45.760 --> 0:12:51.439 so they were projected onto photosensitive paper using a projecting microscope. 0:12:51.559 --> 0:12:56.320 British physiologist John Burdon Sanderson and Frederick Page had used 0:12:56.360 --> 0:12:59.880 a similar device to record a two phase current in 0:13:00.160 --> 0:13:05.439 frog heartbeats in eighteen seventy eight. Waller called this a cardiograph, 0:13:05.559 --> 0:13:08.320 and he did a number of experiments with it, including 0:13:08.400 --> 0:13:12.440 working with different numbers of leads, sometimes a single lead, 0:13:12.640 --> 0:13:17.679 sometimes two, and eventually five. Those five electrodes were on 0:13:17.800 --> 0:13:20.880 all four of the patient's limbs and one in their mouth. 0:13:21.720 --> 0:13:24.760 He used electrodes strapped to the surface of the patient's body, 0:13:24.800 --> 0:13:27.800 as well as jars of saline solution that acted as 0:13:27.840 --> 0:13:31.679 electrodes for the hands and feet. He also did demonstrations 0:13:31.679 --> 0:13:34.720 of this concept with his dog, Jimmy, who would stand 0:13:34.760 --> 0:13:38.520 with two of his feet in jars of saline. Jimmy 0:13:38.600 --> 0:13:40.680 was reportedly a very patient dog. 0:13:42.800 --> 0:13:46.160 While Waller was able to record electrical signals from the 0:13:46.280 --> 0:13:50.520 heart with the capillary electrometer, he didn't really think this 0:13:50.720 --> 0:13:54.400 was going to be useful in clinical practice. He eventually 0:13:54.480 --> 0:13:57.000 came to see more value in it, but earlier on 0:13:57.080 --> 0:13:59.920 he's quoted as saying he didn't imagine that it would 0:14:00.120 --> 0:14:04.520 thee extensive use in hospitals quote that can be at 0:14:04.640 --> 0:14:08.080 most of rare and occasional use to afford a record 0:14:08.120 --> 0:14:11.240 of some rare anomaly of cardiac action. 0:14:12.320 --> 0:14:15.280 One of the people who saw one of Waller's demonstrations 0:14:15.320 --> 0:14:20.080 with Jimmy was Dutch physiologist VILLEM. Eintoven. He had been 0:14:20.080 --> 0:14:23.640 born in Semarang, Java in eighteen sixty and he had 0:14:23.720 --> 0:14:27.760 Jewish ancestry. Ancestors on his father's side had fled to 0:14:27.800 --> 0:14:31.840 the Netherlands during the Spanish Inquisition. His father and his 0:14:31.880 --> 0:14:35.240 grandfather were both doctors, and he earned both an MD 0:14:35.440 --> 0:14:39.520 and a PhD from the University of Utrecht. Ethoven saw 0:14:39.600 --> 0:14:43.720 Waller's demonstration at the International Congress of Physiology in London 0:14:44.120 --> 0:14:49.320 in eighteen eighty seven. After seeing this demonstration, Aintoven started 0:14:49.360 --> 0:14:53.160 working on his own device, describing it as an electro 0:14:53.280 --> 0:14:58.200 cardiogram at the eighteen ninety three Dutch Medical Meeting. Although 0:14:58.280 --> 0:15:02.000 Eintoven is usually credited with coining this term, he actually 0:15:02.000 --> 0:15:05.680 gave the credit to Waller. Intoven started out with a 0:15:05.800 --> 0:15:10.000 five lead setup similar to Waller's, but ultimately dropped the 0:15:10.040 --> 0:15:13.400 two leads that he thought provided the lowest yield for 0:15:13.440 --> 0:15:16.040 the signal. Those two leads were the one in the 0:15:16.080 --> 0:15:20.560 mouth and the right leg. That left three leads for 0:15:20.640 --> 0:15:24.160 both of the patient's hands and their left leg. All 0:15:24.200 --> 0:15:29.080 the electrodes for the setup were buckets of saline. Inoven 0:15:29.160 --> 0:15:32.960 studied the curves produced by this device, noticing that there 0:15:33.040 --> 0:15:36.880 was a pattern of five deflections for each heartbeat. He 0:15:36.960 --> 0:15:42.239 labeled these deflections ABCD, and E. He worked with mathematician 0:15:42.400 --> 0:15:45.360 Heindrich Lorentz to create a formula that would account for 0:15:45.400 --> 0:15:50.040 inertia and friction within the device. The resulting pattern looked 0:15:50.080 --> 0:15:54.280 like what we see in an EKG today. Every person's 0:15:54.280 --> 0:15:57.200 heartbeat is their own, but in a healthy heart that's 0:15:57.240 --> 0:15:59.960 beating normally, the basic pattern is the same. 0:16:01.040 --> 0:16:06.880 Eintoven labeled those five corrected deflections as PQRS, and T. 0:16:07.520 --> 0:16:10.920 He probably chose p AT as the starting point because 0:16:10.960 --> 0:16:13.760 of a tradition dating back to Renee Descartes of using 0:16:13.880 --> 0:16:17.440 letters from the second half of the alphabet. The letters 0:16:17.560 --> 0:16:20.960 N and O were already widely being used for other purposes. 0:16:21.600 --> 0:16:25.000 Aintoven published a paper detailing all this in eighteen ninety 0:16:25.040 --> 0:16:28.200 five called Form of the Human electro cardiogram. 0:16:29.080 --> 0:16:32.160 Then Eintoven started working on developing a device with a 0:16:32.200 --> 0:16:36.680 more sensitive galvanometer. He did this with a string galvanometer 0:16:37.000 --> 0:16:40.840 made from a thread of quartz coated in silver. This 0:16:40.960 --> 0:16:44.320 thread was suspended between the poles of an electromagnet, and 0:16:44.400 --> 0:16:48.160 it shifted within the electromagnetic field in response to the 0:16:48.200 --> 0:16:53.360 electrical signals from the heart. While this galvanometer was more sensitive, 0:16:53.480 --> 0:16:56.720 its movements were still teeny tiny, so they had to 0:16:56.720 --> 0:17:00.560 be magnified and projected onto a running sheet of photographic film. 0:17:01.240 --> 0:17:04.040 He presented this device for the first time in nineteen 0:17:04.080 --> 0:17:04.480 oh one. 0:17:05.480 --> 0:17:08.040 This was pretty similar to a device that had been 0:17:08.160 --> 0:17:13.000 created by French engineer and aviator Clement Adair for receiving 0:17:13.080 --> 0:17:17.320 underwater transmissions through wires. It seems like these two men 0:17:17.480 --> 0:17:20.840 each came up with their devices independently of one another, 0:17:21.000 --> 0:17:24.720 but Intoven later did acknowledge Adair's similar work. 0:17:25.800 --> 0:17:29.760 Although Eintoven's string galvanometer was more sensitive and precise than 0:17:29.760 --> 0:17:33.080 the capillary device had been, that did not mean that 0:17:33.160 --> 0:17:36.680 it was small or easy to use. It weighed more 0:17:36.680 --> 0:17:40.399 than six hundred sixty pounds or three hundred kilograms, and 0:17:40.480 --> 0:17:44.840 it took up two rooms It required a large electromagnet 0:17:44.880 --> 0:17:47.800 which had to be continually cooled with flowing water to 0:17:47.920 --> 0:17:52.240 keep it from overheating, and it required five people to operate. 0:17:53.000 --> 0:17:56.159 So by nineteen oh three Etoven was working on making 0:17:56.280 --> 0:17:59.560 a commercial version of this device which could actually be 0:17:59.680 --> 0:18:05.400 used and clinical medicine. This was not really that would 0:18:05.440 --> 0:18:08.159 be a long process and in the meantime it just 0:18:08.280 --> 0:18:11.520 it wasn't possible to move his device from the laboratory, 0:18:11.560 --> 0:18:14.080 where it took up two rooms, to a hospital where 0:18:14.119 --> 0:18:17.760 it could be used with patients more easily. His colleague 0:18:17.800 --> 0:18:21.280 Johannes Bosha made a suggestion, and that was to connect 0:18:21.320 --> 0:18:24.760 to the electro cardiogram at the lab to the academic 0:18:24.840 --> 0:18:29.000 hospital in Leiden, roughly a mile or fifteen hundred meters away. 0:18:29.960 --> 0:18:33.119 They did this with a telephone line. Patients in the 0:18:33.200 --> 0:18:35.840 hospital placed both of their arms and one of their 0:18:35.920 --> 0:18:40.000 legs in buckets of saline, with those buckets acting as electrodes, 0:18:40.560 --> 0:18:43.440 and they were connected to a telephone line that carried 0:18:43.560 --> 0:18:47.080 their electrical signal to the galvanometer in the lab. 0:18:48.160 --> 0:18:51.080 Then they could read the electro cardiogram in the lab 0:18:51.119 --> 0:18:54.200 almost a mile away. On March twenty second of nineteen 0:18:54.200 --> 0:18:58.040 oh five, the first telecardiogram was transmitted from the hospital. 0:18:58.880 --> 0:19:03.639 Einthoven published a paper called Leutelecardiogram in nineteen oh six. 0:19:04.280 --> 0:19:07.720 This work detailed a number of arrhythmias and other issues 0:19:07.720 --> 0:19:10.639 that could be detected by examining the results of an 0:19:10.680 --> 0:19:18.440 electro cardiogram, including mitral insufficiency, left ventricular hypertrophy, premature ventricular contractions, 0:19:18.560 --> 0:19:23.840 and atrial flutter. By this point, Cambridge Scientific Instrument Company 0:19:23.880 --> 0:19:28.040 of London had developed a commercial version of the Eintoven 0:19:28.200 --> 0:19:32.040 electric cardiograph, and it had sold three of them. All 0:19:32.080 --> 0:19:34.879 three were for use in laboratory research, though not for 0:19:35.160 --> 0:19:39.399 clinical work in human medical patients. The first purchase of 0:19:39.400 --> 0:19:42.520 one of these machines for clinical work was in nineteen 0:19:42.640 --> 0:19:48.000 oh eight. We'll talk about how electric cardiographs and electrocardiograms 0:19:48.119 --> 0:20:00.800 developed from here. After another sponsor break, in. 0:20:00.840 --> 0:20:05.600 Nineteen eleven, Cambridge Instrument Company released a table model of 0:20:05.680 --> 0:20:09.760 William Eintoven's electro cardiograph. This one was still a lot 0:20:09.800 --> 0:20:13.440 bigger than most of today's machines that you might see 0:20:13.480 --> 0:20:16.720 in a doctor's office. It still required patients to sit 0:20:16.800 --> 0:20:18.879 with both of their hands and one of their feet 0:20:18.960 --> 0:20:23.119 in buckets of saline, so it was still relatively cumbersome, 0:20:23.160 --> 0:20:26.120 but it was way more compact than that two room, 0:20:26.280 --> 0:20:30.080 six hundred pound original version, and doctors had also figured 0:20:30.119 --> 0:20:33.359 out all kinds of conditions and abnormalities that could be 0:20:33.400 --> 0:20:37.720 detected and diagnosed through the patterns in an electro cardiogram. 0:20:38.200 --> 0:20:41.159 Doctors and hospitals were a little slower to adopt this 0:20:41.280 --> 0:20:44.440 technology than they had been with the first X ray machines, 0:20:44.800 --> 0:20:47.960 but by the time this table model was introduced, electric 0:20:47.960 --> 0:20:51.840 cardiograms were starting to be regarded as critical to cardiac care. 0:20:52.720 --> 0:20:55.280 We talked about the development of X rays in our 0:20:55.320 --> 0:20:58.800 episode on mimography on January thirty first, twenty twenty four, 0:20:59.200 --> 0:21:01.520 and the modern blood pressure cuff in our episode on 0:21:01.640 --> 0:21:06.040 hypertension on August first, twenty twenty two. X ray machines, 0:21:06.080 --> 0:21:09.679 blood pressure cuffs, and electric cardiograms were all developed and 0:21:09.800 --> 0:21:13.240 refined around the turn of the twentieth century, and together 0:21:13.400 --> 0:21:16.679 they were critical to the development of cardiology as a 0:21:16.720 --> 0:21:21.680 specific medical field. I've also realized these are three episodes 0:21:21.760 --> 0:21:24.960 from our catalog, including this one, all inspired by my 0:21:25.080 --> 0:21:31.680 own medical experiences. In nineteen twelve, Welsh cardiologist Thomas Lewis 0:21:31.720 --> 0:21:36.040 delivered a lecture at University College Hospital titled on the 0:21:36.080 --> 0:21:42.920 evidences of Auricular Fibrillation Treated Historically. He described various arrhythmias 0:21:43.000 --> 0:21:47.040 as clearly visible and recognizable in the waves of an 0:21:47.080 --> 0:21:51.720 electro cardiogram, including fibrillations that is, a heart that's fluttering 0:21:51.800 --> 0:21:55.320 or twitching in an unsynchronized way rather than beating in 0:21:55.359 --> 0:21:59.560 a regular pattern. He also discussed the examination of a 0:21:59.640 --> 0:22:03.760 horse that showed evidence of atrial fibrillation due to heart disease, 0:22:04.600 --> 0:22:08.440 not something that had been induced in the horse through experimentation, 0:22:08.600 --> 0:22:10.320 which had been the case in some of the other 0:22:10.400 --> 0:22:15.000 animal research. He found that the waves from the horse's 0:22:15.080 --> 0:22:17.920 heart were basically the same as that of a human's, 0:22:18.000 --> 0:22:21.760 and he confirmed that the heart really was in atrial 0:22:21.800 --> 0:22:25.800 fibrillation by actually looking at it during a surgical examination. 0:22:26.920 --> 0:22:30.080 Lewis was a regular correspondent with Einthoven, and he was 0:22:30.160 --> 0:22:33.840 also building on the work of Scottish cardiologist James Mackenzie, 0:22:34.080 --> 0:22:37.880 who developed a polygraph machine that traced patient's pulses at 0:22:37.880 --> 0:22:41.560 the wrist and neck, which could also show evidence of arrhythmias. 0:22:42.400 --> 0:22:45.760 This was simpler than the polygraph machines that supposedly work 0:22:45.760 --> 0:22:50.680 as light detectors. Today those also measure other physiological responses. 0:22:51.560 --> 0:22:55.160 Like Augustus Waller, who we mentioned earlier, Lewis didn't really 0:22:55.200 --> 0:22:59.040 think electric cardiograms could be very useful in clinical medicine, 0:22:59.600 --> 0:23:03.720 but this largely because they were still pretty cumbersome. ECGs 0:23:03.800 --> 0:23:07.080 could only capture a few seconds of activity, and since 0:23:07.080 --> 0:23:10.760 the results were projected onto photosensitive paper, they had to 0:23:10.800 --> 0:23:15.080 be developed before they could be interpreted. But Mackenzie's polygraph 0:23:15.240 --> 0:23:18.320 used ink on a running roll of paper, its pulse 0:23:18.359 --> 0:23:23.439 tracings were visible immediately. Lewis also noted that at this point, 0:23:23.720 --> 0:23:28.040 treatment for suspected cardiac issues was the same regardless of 0:23:28.080 --> 0:23:31.200 whether a person had been given an electric cardiogram or not. 0:23:32.200 --> 0:23:36.600 As the technology improved, though, Lewis updated his opinion, saying, quote, 0:23:36.880 --> 0:23:39.960 the time is at hand, if not already come, when 0:23:39.960 --> 0:23:43.280 an examination of the heart is incomplete, if this new 0:23:43.359 --> 0:23:48.080 method is neglected. Eindoven was still making new discoveries, and 0:23:48.200 --> 0:23:52.080 in nineteen twelve he described his system of three leads 0:23:52.160 --> 0:23:56.600 as an equilateral triangle that the concept known as Eindhoven's 0:23:56.600 --> 0:24:00.720 triangle today. His written work on this it was probably 0:24:00.760 --> 0:24:04.080 the first use in writing of the abbreviation EKG. 0:24:05.520 --> 0:24:10.440 In nineteen eighteen, physician and professor James Herrick of Chicago 0:24:10.520 --> 0:24:14.159 demonstrated that it was possible to use an ECG to 0:24:14.280 --> 0:24:19.480 diagnose a myocardial infarction commonly called a heart attack. American 0:24:19.520 --> 0:24:24.400 cardiologist Harold Party published work on diagnosing coronary artery obstructions 0:24:24.680 --> 0:24:29.400 through electric cardiograms in nineteen twenty. In nineteen twenty four, 0:24:29.600 --> 0:24:33.239 Villain Einsoven was awarded the Nobel Prize in Physiology or 0:24:33.280 --> 0:24:37.600 Medicine for his discovery of the mechanism of the electro cardiogram. 0:24:38.119 --> 0:24:41.600 The presentation speech made it clear that this award was 0:24:41.680 --> 0:24:47.120 not only about Eindhoven's development of the electro cardiograph device. 0:24:47.760 --> 0:24:52.280 It was also about his interpretations of the electro cardiograms, 0:24:52.720 --> 0:24:57.720 what pqrs and T each corresponded to in a beating heart, 0:24:58.040 --> 0:25:02.000 and how to identify so many different disorders and diseases 0:25:02.000 --> 0:25:05.560 of the heart through the analysis and interpretation of that 0:25:05.680 --> 0:25:10.880 one wave. Other researchers had offered other methods of interpretation, 0:25:11.080 --> 0:25:14.400 but in the words of the award speech quote, Eintoven's 0:25:14.440 --> 0:25:17.960 concept is the only one which has proved to be tenable. 0:25:18.880 --> 0:25:22.240 The Nobel prize came with a monetary award that Eintoven 0:25:22.280 --> 0:25:25.119 wanted to split with his assistant, who had worked with 0:25:25.200 --> 0:25:27.280 him during the early years of his work and the 0:25:27.320 --> 0:25:31.639 development of this device. His name was von Deiverd. Vondiverd 0:25:31.680 --> 0:25:35.679 had died, though, and Eintoven instead divided the forty thousand 0:25:35.720 --> 0:25:39.080 dollars prize money with Vondiverd's two sisters, who had been 0:25:39.119 --> 0:25:43.440 living in poverty. Three years later, on September twenty ninth, 0:25:43.520 --> 0:25:48.560 nineteen twenty seven, Billem Eintoven died of cancer. Also in 0:25:48.640 --> 0:25:53.040 nineteen twenty seven, Japanese physician Tarro Takem developed the first 0:25:53.200 --> 0:25:58.520 portable ECG machine. Two years later, the Sanborn Company of Waltham, 0:25:58.600 --> 0:26:03.399 Massachusetts released the Sanborn Visocardiac, which was a portable version 0:26:03.440 --> 0:26:06.040 that could print the results immediately on a roll of 0:26:06.080 --> 0:26:09.679 paper that weighed about twenty six pounds or twelve kilograms, 0:26:09.680 --> 0:26:13.119 and it was powered by a car battery. In nineteen 0:26:13.160 --> 0:26:18.240 thirty four, physiologist Frank N. Wilson started working on standardizing 0:26:18.280 --> 0:26:22.399 the use and placement of electrodes and leads. He realized 0:26:22.440 --> 0:26:25.439 that the typical three lead system left some areas of 0:26:25.440 --> 0:26:28.840 the heart that weren't fully represented in the ECG wave. 0:26:29.720 --> 0:26:33.560 He added another lead, described as an exploring lead, which 0:26:33.600 --> 0:26:36.600 could be used along with the three standard leads to 0:26:36.680 --> 0:26:40.040 read the electrical activity of specific parts of the heart. 0:26:41.040 --> 0:26:45.160 I couldn't pinpoint exactly when these machines moved away from 0:26:45.240 --> 0:26:48.160 having people put their hands and feet in buckets of saline, 0:26:48.400 --> 0:26:51.840 but these exploratory leads typically went somewhere on the chest, 0:26:52.000 --> 0:26:55.280 so they would have used surface electrodes at some point, 0:26:55.280 --> 0:26:59.240 though ECG's did start to use only electrodes that were 0:26:59.280 --> 0:27:03.800 placed on the body. Today, these are usually little adhesive discs. 0:27:04.600 --> 0:27:08.120