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Aanar t1_ir1fng2 wrote

Reply to comment by TheTimeIsChow in Georgia doctor implants one of the first wireless, dual chamber pacemakers: New type of pacemaker is safer option than traditional surgery by universityofga

My guess is it's only recommended for older patients? I don't think they can be easily explanted and there isn't room to put a new one in every 12 years over 70+ years.

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GimmickNG t1_ir1m4mh wrote

From the OP,

> The wireless pacemaker is about 90% smaller than the average pacemaker and the surgery lasts around 30 minutes. The battery life is also comparable with a traditional pacemaker’s 10-12 years and could be longer in some cases. Patients also will not have an incision scar on the chest or a bump protruding from the skin.

So if it's 90% smaller then there should be enough room to put in a new one every 10-12 years, unless people start living older than 100 with this device.

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Aanar t1_ir1nb9k wrote

They go in different places. This device is actually within your left ventrical. In a traditional pacemaker, only the lead is in the ventrical (and another in the atrium possibly) with the device located in a pocket under the collar bone. Traditional pacemakers are explanted when you need a new one. If the leads are still in good shape, the same leads are used with the new pacemaker, so there's no new net increase of volume of product being placed. If the lead isn't useable, then yes, they typically just put in a new one rather than try to extract the old one since explanting them can be risky. After about 3 or 4 leads though, you run out of room.

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pavelbure- t1_ir22ce0 wrote

AFAIK, the issue is the leads and human heart tissue. Cardiac tissue is partially conductive (conceptually, there are embedded, invisible, conductive channels).

It's not like skin, where you can re-implant into scar tissue or re-implant very close to another implantation location. The signal won't carry through the scar tissue. The lead wearing out (and coming out) comes with commensurate tissue scarring in an area. After a few implantations, you don't have a location that will carry the signal, reliably, as if it was natural cardiac tissue.

You want to replace/repair as few times as possible, to extend the utility of a pace-maker.

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mortenmhp t1_ir240tv wrote

Definitely. At least for the Micra, which is the only cordless in general use here we mostly use it for the most frail patients where we worry if the surgery of a regular pacemaker will be an issue or that the skin will heal properly if they have barely any body fat. If not for the price it'd probably be more popular, but even then we wouldn't recommend it if there were a chance of the patient outliving the battery.

The article says he implanted it in a 64 year old woman, which imo is way too young unless they plan to be able to remove it(doesn't look like it)

I'm curious how this is supposed to be a dual chamber pm though? Being cordless would almost by definition mean only having direct contact with the right ventricle. I'm wondering if it is just like the Micra av that tries to sense the atrial contraction to synchronize. That's not really dual chamber though. The article doesn't specify and I'm not very familiar with Abbott's cordless models.

Edit: looking up the aveir, it looks like they actually use 2 individual devices, one for right atrium and one for right ventricle, which communicates wirelessly. Neat. Also they wrote that it's designed to be extractable, which is nice i guess, but it is never unproblematic to remove something screwed into the heart. There is a reason leads are not rarely left even if they could be extracted.

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TheTimeIsChow t1_ir245db wrote

My guess, well my hope at least, is that this isn't the case.

I'd imagine that the lead/tip scars over into the heart wall and acts like a normal pacemaker wires lead. Then the device itself can be replaced. Whether it be 'unscrewed' or detached from the lead/tip in some way.

You could 100% be right. But I'd imagine this would be very high risk should the device see a premature failure and need to come out.

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