> Currently used blood pumps have many disadvantages: their mechanical parts are susceptible to complications while the patient lacks a physiological pulse, which is assumed to have some consequences for the patient.
Kind of weird, but apparently people with artificial hearts that don't give a pulse don't really suffer any obvious consequences:
I've often wondered, but have never heard anything one way or the other, if not having a pulse might not be better. I mean think of all of the physical things that have reduced lifespans due to pulsing. Whether it's high frequency like vibration, or low frequency like when your car's brake rotors are warped. Not only do the brakes not work as well, it's hard on wheel bearings and to a lesser extent suspension parts. Or did our vascular system evolve to rely on that pulse? Like, I dunno, helps keep arteries clear or something.
Unfortunately, last I paid attention, artificial heart patients don't live long enough to make an evaluation.
> I'd like to see these things in every Hospital asap
Yes sir, right away sir.
Seriously though, Ventricular Assist Devices have been available for decades. I have worked with clients who make them. You can get one today if you have heart failure through your insurance company while you're waiting for a transplant.
When they say:
> The reasoning why nature should be used as a model is clear. Currently used blood pumps have many disadvantages: their mechanical parts are susceptible to complications while the patient lacks a physiological pulse, which is assumed to have some consequences for the patient.
In fact, it's not clear at all (always, always remember the Gell-Mann Amnesia effect). The first generations of VADs were pulsatile because they "assumed nature" should be a model and they had many problems in patients.
Then the next generation of continuous rotary pumps came out and are the only ones (in fact only 3 pumps today are used, HeartMate II, HeartMate III and HeartWare HVAD) that last for years. btw 180 days is the typical wait time for a transplant. Then artificial pulsatility was added to the rotary pumps, mostly out of an imaginary need for a pulse, but no one has been able to prove a pulse is necessary.
As this is a project by a materials research group, I'm confident this is a pilot project and their goal will be to improve the lifetime of the materials by X%. That means, it will be a long, long time before this style of pump is found in bodies. Notice they're not assessing thrombosis or hemolysis, etc.
If you sincerely want to reduce heart disease, focus on improving peoples' diets, exercise and stress/sleep. That will have the most effect. For many people, damage is self-inflicted and they ruin enough of their vasculature and organs that a replacement heart won't do any more than a new power supply on a dead motherboard.
>> I'd like to see these things in every Hospital asap
>Yes sir, right away sir.
If I seem a bit emotionally invested in the topic, it's because I am. My dad died from a heart attack a little under two years ago. One of the side-effects for me has been noticing articles about advancements in the field and caring about them more than I used to. If he had died from it before anyone could potentially do anything, that'd be one thing. But that's not what happened. Medical staff was on-site within minutes. They even claimed he was still alive by the time they arrived at the hospital. But still, he died. He was a month shy of 60.
Of course if he had improved his diet and shed some pounds, he might not have found himself in that situation to begin with so early, but given that heart failure is the number one killer in the US, I don't think that answer is good enough by itself. We need to get to the point that we can save people more consistently.
Heart disease killed more than 10 times as many people in 2016 as any sort of gun death in the US. We should be a lot more concerned with solving this problem as a society.
It's not just big guys like my dad who are at risk. My six year old niece has a small heart defect that could be a problem at some point. You'd think that's pretty rare, but according to some studies, that makes her 1 out of 100 kids.
There are two problems with this lifetime and power supply in that order. The first is that the lifetime was only 3000 beats, which at 40 beats a minute translates to about an hour and a half of use. In comparison, the jarvik 7, one of the first artificial hearts was used in a patient for 620 days[0], which at 40 beats per minute translates to about 36 million beats.
In my opinion, I think it will be very difficult to modify this heart to last this long, especially if it experiences significant elastic deformation. To get this significant elastic deformation we need soft materials like elastomers, which don't tend to have very good fatigue properties under significant elastic deformation. The authors even admit that "this issue is a game breaker and
needs to be resolved."[1] Developing elastomers that can withstand the number of cycles is quite challenging.
This heart is pneumatically powered, so the patient needs to have tubes going through the skin connecting to a pneumatic power supply. These can be bulky, they can be portable, but still somewhat bulky[2]. For something that keeping you alive, this may not matter too much if the benefits of using the device are sufficient.
Although I'm not really clear on what the benefits of using this are(I must admit I am not an expert in artificial hearts). One big claimed advantage is that they may reduce the dead spots in the heart. Dead spots are regions of low fluid flow, these are bad, because they can cause clots to form. Some artificial hearts deal with this now by having the patient take anticoagulants, so reducing them is a pretty big deal. But they have not demonstrated this. Although this is pretty difficult to do, they'd have to find a way to make the heart transparent to see the fluid flow inside.
As far as I recall, this is not the first soft heart. Previous attempts were made out of synthetic fabrics alleviating many problems with elastomers, for valves and aorta patches. If these fabrics were electrically sensitive, they could beat, problem being biocompatibility.
Jarvik-7 is not a whole heart, it is an LVAD. And yes it has a pulse due to pump peristaltic action as opposed to some continuous flow devices.
I wonder if we could have heart wrapping aid. For some people with partially failing heart, not structural but more like dead tissue, an external pressure help from the wrapper could help restore proper blood pressure without requiring replacement.
