For those that may be interested- dual chamber leadless PM

Leadless technology

by Gemita - 2022-02-23 14:13:34

Dave, thank you for this information.  Perhaps leadless pacemaker technology is slowly on the move?  

I picked up a magazine recently in my pacemaker clinic about a heart failure patient from Kent, UK who received three leadless heart devices under my consultant and I attach a link below.  Sorry to hijack your thread with this, but I thought it might add to the conversation about leadless technology generally.

Are you wishing to change to leadless technology in the future?

https://www.guysandstthomas.nhs.uk/news-and-events/2020-news/march/20200316-world-first-as-patient-benefits-from-three-wireless-heart-devices.aspx

Gemita-Thanks

by Good Dog - 2022-02-23 14:48:10

Thanks for that info! I'll check it out. I was recently diagnosed with pacer induced cardiomyopathy. Obviously, my lead placement over 35 years ago was apical. Unfortunately, I already have two leads through my tricuspid valve. The first one was recalled, capped and left in-place. So my active RV lead is only 27 years old. I would love to go leadless (sounds kinda erotic), but I don't think I am a candidate. My EP is the head of research at the Cleveland Clinic here and is involved in the trial, so if it weren't for my "issue" I might have had a shot at it. After my EP told me about all the risks of extracting leads and the fact that he doesn't like to do it unless there is no alternative, he informed me that he needs to extract mine! Sorry, I know that is more than you needed to know.

BTW: interestingly enough, I live in Kent (Ohio)

Thanks again..........

EDIT: I just checked-out that article! Wow, sounds a little like my situation. Great article and really interesting! If there weren't any more after the guy in the article, I'd like to be the 2nd person.

Sincerely,

Dave

Neat!

by AgentX86 - 2022-02-23 15:15:40

But it raises a lot of questions (that aren't within a mile if that press release). Just a couple:

How does the atrial half stay in the atrium?

It seems like this would be very sensitive to EMI.  I wonder what technology they're using to mitigate high RF fields.

What happens to the atrial PM when the battery dies?  The RA isn't all that big.

Three lead: Hijacked?  It's relevent, IMO.

Interesting, though I'd count it as only two leaded pacing (the third is outside the heart and an ICD only).  Instead of a two-lead (RA + RV), like the above two lead, this is a two lead CRT (RV + LV). I have the same question about EMI but it does sound interesting for VVI(R) pacing. Is the LV PM inserted through the femoral artery, instead of vein like normal PMs and CRTs?

?

Dave and AgentX86

by Gemita - 2022-02-24 05:05:04

https://bjcardio.co.uk/2018/10/leadless-pacing/

Dave, Lots more questions than answers about leadless pacing systems.  Yes I too would love to go leadless but not sure that I will see this technology perfected in my lifetime.  I will have to check out Kent in Ohio.  I live in Kent in the UK.  What a coincidence.

I wasn’t sure how a leadless device was held in place to prevent movement until I read the above link (copy and paste the link into main browser to view).  The link might also be useful to answer other questions about leadless pacemakers.  I see that the Micra device (for Medtronic at least), is anchored into cardiac tissue by way of an active fixation mechanism system consisting of “electrically inactive tines”.  This allows the device to be placed and held securely at an optimal implant site where adequate signals can be received from the heart. 

I see you have removed your comment about His Bundle placement?  As you know, this can still be technically difficult for the operator to optimally place at this site even with a conventional lead pacing system so I presume we are some way off from getting a leadless device to successfully pace here?

End of Service.  The Medtronic current Micra device isn't intended to be removed at the end of battery life and that would concern me, although I see Abbott has designed the Aveir DR leadless pacemaker to be retrievable, so the system can be replaced.  Removal of the device may be difficult though so we would still need a really skilled technician (like with lead removal) to carry out an explant. 

AgentX86, some challenging questions as usual!  You suggest the link I provided shows a two, rather than a three, leadless device pacing system.  I suppose I think all ICDs are pacemakers to a degree with anti tachycardia and/or bradycardia pacing, as well as being able to shock the heart to prevent sudden cardiac death from a dangerous ventricular arrhythmia.  If Robert's ICD has one or both of these pacing capabilities, then the link could be thought to show a "three leadless pacing system".  Robert clearly has three devices although I appreciate he is being paced in both ventricles whih seems amazing.  Not sure about the access site - ?femoral artery?

Gemita - HBP - Kent

by Good Dog - 2022-02-24 10:28:08

Thanks for the follow-up. Yeah, I removed the post, because I realized that currently HBP is highly unlikely at least for now, and not likely to be available in my lifetime. That caused me to lose some interest!

BTW: When at the Clinic a number of years ago one of the Docs handed me one of the Micra PM's and said; "check this out". As you might imagine, it was smaller than a standard AAA battery. Pretty cool technology. Anyway, Kent, Ohio is a college town. The 2nd largest college in Ohio behind Ohio State. It is a very progressive community and a great place to live. It is a secret though, so don't tell anyone. The only problem is that in northern Ohio we have dreadful winter weather, but the spring, summer and fall weather is really nice.

Abbott Aveir DR i2i and Medtronic Leadless Systems

by Marybird - 2022-02-24 16:07:24

Look like to different systems to me, looking at the linked Abbott and Medtronic articles.

Seems the Medtronic system involves three leadless devices, a pacemaker in one ventricle, a  resynchronization (CRT) device in the other ventricle ( I'd assume that's where it went), and a third device, an defibrillator/converter planted under the skin somewhere in the general area of the chest. The three devices communicate with each other via wireless technology, and synchronize their activities.

The Abbott system consists of two separate wireless pacemakers, one implanted in the right atrium, the other implanted in the right ventricle, and the two devices communicate by wireless communication. They tout this system as being able to pace the heart in the same way as a regular two chamber pacemaker.

The other point mentioned by Abbott for its system is that it's meant to be retrieved from the heart when indicated, there's a device removal tool with the system.

Here's another link for the Abbott system:

https://www.massdevice.com/abbott-confirms-implants-of-dual-chamber-leadless-pacemaker-in-trial/

The article that Gemita posted for the Medtronic system came out in 2020, though it looks as though that system isn't yet ready for prime time. Not sure where it is these days, if clinical trials have been set up or are ongoing. Looks as though the Abbott system was just recently announced, and they're looking to set up clinical trials.

Interesting, though I'm still not so sure about multiple devices floating around in the chambers of the heart, don't care how well they are attached. But that is me. I'm too old, but for anyone who might be eligible for one of these systems and is interested in possibly getting into a clinical trial or getting one of these devices, I say more power to them.

ICDs

by AgentX86 - 2022-02-24 18:19:34

Gemita, From what I understood from the article is that the external device is only an ICD with no pacing function but that it is communication with the two intraventricular pacing devices.  Then they detect a dangerous arrhythmia, they instruct the ICD to provide the "Jesus Jolt", as Robo would say.  This makes sense since there is already a pacing device in each ventricle.  An internal ICD would be problematic, too, since the necessary battery is large and may need to be replaced more frequently than a PM. Even if it's designed for it, retrieval will be a difficult procedure. The devices are attached to the heart wall with several inactive tines, as well as the active tine. Think of a thisle in a dog's fur. ;-)

The veins (except the pulmonary vien - the lungs are backward) all end up in the right side of the heart.  To place an RA, RV, or even LV lead, the leads are fished from the femoral vein up into the vena cava and into the RA. The LV lead takes the same path because it really isn't placed in the LV, rather in the coronary sinus which is accessed from the right side.

The left side of the heart is only connected to the pulmonary vein and the aorta so the only practical way to get to it is from one of the arteries.  The femoral is the largest and it's a straight shot to the aorta.

Ablations access the LA by "punching" through the septum from the RA to the LA, so access is from the RA and femoral vein.  Veins are a lot easier because of the much lower pressure than arteries (arteries make a real mess when cut). Note that cardiac catheterizations are usually done via the femoral artery so it can be done, just that it's a little more difficult. (The right radial artery can also be used for cardiac caths by specially trained cardiologists)

leadless

by new to pace.... - 2022-02-24 19:34:01

This is all just to complicated for me.   At 81, do not believe i will be or want to have this in my life time. Nor do i think they will want to have me in their trial.  Will leave this for those coming along behind me.

new to pace