Future of Pacing
One day, stem cell research will lead to the regeneration of conductive tissue and therefore pacemakers may become obsolete. Until then we look to the science of implantable devices to treat heart blocks and heart failure. The good news is that even though pacemakers are pretty darn good, innovation is not resting on its laurels but instead the future look seven brighter, below we have a look at the future of pacing.
Future of Pacemakers Revealed
Leadless and Scar-less
Surgery in general is always looking to become less invasive, from keyhole knee surgery to valve replacements, science is finding ways to make larger alterations to the human body with a smaller surgical footprint. In Cardiology, the ability to gain access to the heart using minimally invasive techniques has been in practice for decades but pacemakers have been left out because of their size. That is until recently, where both the St Jude Nanostim and the Medtronic Micra unveiled as pacemakers that are introduced to the heart through a catheter inserted in the patients arm or leg! These devices are limited to VVI functionality. The future is quite clearly in dual chamber and complex devices that can be delivered and deployed into the heart itself via a catheter. There are Patents on the internet that certainly suggest one company is certainly heading down this route. ‘Dual Chamber’ Leadless Pacemaker Patent.
The introduction of transcatheter pacemaker implant would certainly open the door for speedier procedures. The omission of sutures from the procedure would in itself save time. However, when I consider ‘quicker’ implants in pacing, I think of the times where I am stood at the side of a Cath Lab watching the Cardiologist try for hours to gain access to a suitable vein and indeed the coronary sinus. These are the vital parts of Cardiac anatomy in Biventricular pacemaker implants and can be illusive.
If only the doctor had been able to see exactly the anatomy of that patients heart before the procedure…
I’m pretty sure knowing exactly where to put the catheter would save time and as an added bonus this would also reduce the exposure to radiation of every one involved. Read more about the holograms here.
|Image Courtey of http://www.tyrx.com/index.htm|
Whilst the introduction of a pacemaker through a Catheter will all but remove infection of the pacemaker implant site, there are advances that will be introduced before that day comes that look at reducing infection rates. This advance in technology is pretty self explanatory in that pacemakers and other implantable devices will be coated with an anti-infective agent. The patent was registered some years ago and so it is only a matter of time before they are in general use. Currently available is aigis. Aigis is a mesh pouch that holds the pacemaker in place and elutes an antibiotic after the device has been implanted. Developed by Tyrx it has now been snapped up by Medtronic.
The battery of the pacemaker is sure to change. Whilst the average pacemaker will last around 10 years this still means multiple procedures for younger patients. The technology to recharge a battery through the skin is already in existence in fact it has been since 1965. However, this idealism of the rechargeable pacemaker died out quicker than a couple of Duracells. Despite sceptics suggesting that it wouldn’t have allowed the pacemaker manufacturers the ability to sell another to the same patient every 10 years, it really boiled down to the fact that if a pacemaker is there to keep someone alive you do not want to rely on their ability to charge it. Actually there are benefits to the battery running out, in that your new pacemaker will include 10 years of advanced technology since your antiquated one was implanted (Facebook wasn’t around 10 years ago!).
Longevity of battery is really more of an issue in ICD’s where therapies can drain battery very quickly less than 3 Years in some cases. So there is a market for a rechargeable functionality but not where the patient is responsible. There are two front runners in this market Biothermal Batteries and Piezoelectric Nanoribbons.
The battery is ‘charged’ by harnessing the differences in temperature that exist just a few millimeters beneath our skin (up to 5 Degrees C in some places). This would then trickle feed the standard ICD battery and prolong its life to more than 3 decades!
|Image courtesy of openi.nlm.nih.gov|
The nanoribbon converts the kinetic energy of the hearts own beat into battery power. The hearts beating will cause the ribbons in the ‘battery’ to bend and this movement generates tiny amounts of electricity that build up over time to useable levels.
|Image Courtesy of tahirthehacker.blogspot.com|
In most newer pacemakers there is the ability to download information from them remotely and send that information via a phone line to a healthcare centre or professional. It was shown by a gentleman called Barnaby Jack in 2012, that a pacemaker could be ‘wirelessly hacked’ and therefor the persons life could be vulnerable to cyber crime. Barnaby Jack died days before revealing how exactly this hack was performed. Whilst Dick Cheney lead the way by having the ‘wireless’ functionality of his device disabled to protect him from cyber crime I would speculate the chances of falling victim to this are less likely than being struck by an asteroid. HOWEVER it is an area where greater security should exist and there is already the development of a uncrackable password to access pacemakers and ICD’s. This password is the exact rhythm and rate of the persons heart.
Researchers at RICE University have developed a system where the pacemakers own ECG is used as a biological source for generating instantaneous true random numbers which is shared between the device and the programmer that is in contact with the body. This truly random signal cannot be predicted or faked by somebody who is further away and is therefore protected from cyber crime.
Every bodies hearts are different and as a result pacemakers are not perfect. Especially when we are looking at Biventricular Pacing and the resynchronising of somebodies heart beat. Currently we have two or three points in these pacemakers where we can initiate a heart beat. The points at which we can do this are dictated to us by an individuals anatomy. What would be incredible would be if we had total control over the order of cell depolarisation (contraction) in the heart, this would enable us to truly improve a persons cardiac output to its maximum potential. 3D Printing is opening the door to this innovation. The universities of Illinois and Washington are using 3D Printouts of a Heart to produce a customised elastic membrane almost identical to the outer layer of the heart. The membrane that has electrodes built in could one day be used in the near perfect detection and treatment of cardiac rhythm disorders.
The membrane is shown below attached to a Rabbits Heart.
The design of these pacemakers would certainly allow them to outperform existing pacemakers in terms of rhythm detection and resynchronisation. Would these mean the end for pacing as we know it today? No I do not think so, customized devices would possibly offer choice over conventional Biventricular Pacing maybe in non responders, but the invasive nature and predictable cost would mean that conventional pacing still picked up the lions share of the bradycardic patients.
Further explanation around these topics and more is available in the book Pacemakers Made Easy by Carl Robinson.
NOW I invite you to leave a comment with your visions for the future of pacin…
So in 10 Years I will revisit this post and see just how wrong/right we were!
Thank you for reading