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Guest Editorial

Interview With Dr. Alois Langer

Jodie Miller

March 2003

First, let me say what an honor it is to be included with inventors like Edison, Bell, and Tesla. These are people I read about in history books. I actually got involved with Dr. Mirowski by first being hired by a company in Pittsburgh called Medrad. Dr. Mirowski and Medrad President Dr. Steve Heilman had met previously to my involvement they had negotiated an arrangement where Medrad was to develop an automatic implantable defibrillator. It was indeed the death of a friend that started Mirowski's quest for the realization of a viable implantable defibrillator. I was hired by Medrad as the project engineer for the device's design and development. The first time I met Dr. Mirowski, he and Dr. Mower were at Sinai Hospital of Baltimore, and Steve Heilman and I went down to visit. I had already been hired to work on the project. That was well before 1980, about 1972 or 1973, I'm not good with dates. At this time, the project from our point of view was just beginning. Dr. Mirowski had previously been working with Medtronic, even before his arrangement with Medrad, but for whatever reason Medtronic chose not to pursue it.. Actually, initially the team consisted of a total of four members; Dr. Heilman, Dr. Mower, Dr. Mirowski, and me. I was the engineering member of the team, doing most of the design/engineering work. We didn't start off knowing right away exactly how we would accomplish our goal because it was a fairly complex development project and of course there were those that said it couldn't be done. At first, we began by learning more about defibrillation thresholds, and we did a lot of test defibrillations to test different defibrillation waveforms and to learn how to reliably detect ventricular fibrillation. We probably spent the most time on electrode design, trying an incredible variety of electrodes including intravascular catheters. There was a lot of work that went on during this time with test devices; we would drive down from Pittsburgh to Baltimore to see how well they worked. This was all in the early 1970s. In 1976, we pretty much knew how to do it, and that s when the first actual design for an implantable device was finished, at least regarding the drawings/engineering specifications. After proceeding through extensive testing, which was very rigorous (including animal testing, design reviews, etc.), the first implant was in 1980. Actually, I was in the operating room when the first unit was implanted at Johns Hopkins. Luckily we had built two initial units, because we always had this fear that someone would drop it or it wouldn't work after sterilization or something like that. Well, my job was to test the defibrillator there was a way of testing the defibrillator while it was still in its sterile package I would then open the package and the nurse would pick the unit up and maintain sterility. Everything was going great during this first procedure, until she picked it up and did indeed drop it! So I tested the second unit and we were able to implant that one. Weeks later we tested the device by inducing fibrillation and waiting for the device to shock. Those were perhaps the longest seconds of my life and Dr. Mower was about to manually defibrillate the patient when the implant kicked in. To the best of my knowledge the patient did well, but I do not know what ultimately happened to her. I haven t really kept up very well with the results, but it is my understanding from the literature that your data are correct. In some of the earlier devices, we did have one issue in that the very first devices were designed to detect ventricular fibrillation and fairly rapid tachycardias. We later learned there might be a need to shock a patient s lower rate ventricular tachycardia and our detection system had to be modified to do that. So there were some issues regarding the detection, but that was later resolved by detecting heart rate more accurately than we were able to at first. The earliest devices also detected VF slowly for subsequent shocks because of an electrode polarization phenomenon that we had not seen on our animal testing. This was quickly corrected. Designs have evolved and newer models are clearly very different now and I believe more effective. All of the devices are microprocessor controlled, allowing increased capability, and our initial model was not. There were really no microprocessors available when we started that were of low enough power to do the job. Newer devices also have more effective biphasic waveforms and can be made much smaller. Largely I would have to say it was antiarrhythmic drugs that were being used at that time. Some people were also working on anti-tachycardia pacemakers; they would not be effective for defibrillation, though they could, in some cases, break tachycardias. Unfortunately, they could also cause fibrillation. So someone could have a ventricular tachycardia and the anti-tachycardia pacemaker could either break it, which would obviously be a good result, or induce ventricular fibrillation. Now, it turns out, these devices are combined in one unit. The defibrillator may do anti-tachycardia pacing as a first therapy. Actually, I had one of the very early patents on a combination device it s a microprocessor-controlled anti-tachycardia pacemaker and cardioverter-defibrillator combined with a regular pacemaker. We wrote that patent in 1981. Well, regarding the defibrillator alone, although I have never counted them up, I would say there are about 25+ patents. I have since, as you know, been working on a real-time heart monitoring device for outpatient monitoring, which is also covered by several patents. There are some really exciting things going on right now, unfortunately we are not ready to go public with them at this time - stay tuned. Otherwise, we are progressing fairly well and continuing to sign on new users of the system. It works very, very well, and we do a "user-satisfaction" survey when the patients come off service. One of the very pleasing results is that the patients really love it. They feel very secure because their hearts are being monitored with essentially the same scrutiny as if the patient were in the step down unit of a hospital. The patient transmitter has an alarm button on it which the patient can use to manually activate a transmission. One user said she pushed the button and got a call from Cardiac Telecom within about 15-20 seconds. The patient said that if I do that in a hospital, I usually don t hear anything for minutes perhaps much longer! The patients at home are monitored 24 hours a day, 7 days a week, as long as they are wearing the transmitter. They do periodically take it off, to take a shower for example, and they inform our monitoring center before doing that, so we know when our patients are not being monitored as well. To date we have monitored well over one thousand patients, saved lives across the entire country, have Medicare and Highmark Blue Cross/Blue Shield policies specific to our service and are recognized as both the leaders and pioneers of outpatient telemetry monitoring. More importantly, I have had the satisfaction of seeing this system bring security and peace of mind to cardiac patients and their families. I actually went to a patient s home in Maryland to do the patient education and hookup. When I introduced myself to this post-CABG patient and told her I was the designer of the HEARTLink System she gave me a big hug. What could be better than that? The product was actually my idea it was brought on by my early defibrillator experience. I met some of the early patients and their families, and the one common theme was that the families were very anxious because the early implant candidates were survivors of at least one cardiac sudden death episode. For example, they had an episode of VF and fortunately were resuscitated. So many family members felt they had to watch their loved ones continuously. One woman specifically had trouble sleeping because she had called 911 when she awoke one night and her husband was non-responsive. She was concerned it would happen again and was afraid to sleep. Thus, I had the idea for a patient worn device that could monitor patients at home 24 hours a day. I thought at the time it might be usable for certain less serious arrhythmias than VF, but then I decided it could be a full blown system that could monitor a very wide variety of arrhythmias similar to a Holter monitor but that runs for a longer period of time, on the order of several weeks. I believe I had the idea around the time of the first implant in 1980 but really didn t start working on the system in earnest until 1989 or 1990. After wishing I could pursue the idea for several years, I was finally able to start the company. It was not easy, of course, to start a company; probably the biggest problem was in raising the initial funding; again I heard it couldn't be done, particularly a reliable cardiac event detection algorithm for ambulatory patients. We also had to break new ground with the FDA. But through all of that, it has been worth it. I am pleased that it has made everyone aware that it exists and just how effective it potentially is. If anything, it will increase the number of units that are implanted, that is my opinion at least. In fact, that is what is going on now there are a variety of studies that have expanded the indications for use. So if anything, the unit is going to be implanted into increasingly more people. 


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