Intermittent high pulse after cardioversion

Afib?

by AgentX86 - 2022-12-13 22:28:01

The heart rate of 100bpm makes sense.  Your "Afib" doesn't get to 130bpm so your PM doesn't do the mode switch. The DDD to DDI doesn't make sense to me but the logic behind this sort of mode switch has always escaped me. I could understand DDD to VVI but that's not the deal.

What I don't understand is your comment "300 - 500+ bpm when I had full Afib". Afib doesn't have rate anything like that.  Are you sure that you don't have Aflutter, rather than Afib?  I had (still have, technically) flutter at 240-400bpm but a heart rate of 1/3, 1/4, or 1/5 of that (jumping from one to the other randomly), so had a heart rate something like yours. It felt like AF (I've had that too) because it was irregular but it was AFL.

Apples and Oranges

by sgmfish - 2022-12-13 23:10:55

Hello AgentX86,

Right, VVI sorta makes sense to me too, but my St Jude Medical PM2272 has settings that make it clear that the mode switch is between DDD and DDI.

I had Aflutter at first, and that got solved with an ablation to the R-atrium. Somehow the ablation uncovered the SSS so I ended up with Bradykardia (35 bpm). Next the PM install. Now the Afib. I think the misunderstanding is that I should not have said "300 - 500+ bpm". All the other bpm numbers were actual pulse numbers created by the ventricles. When I said "300 - 500+ bpm" that was from the PM device check reports that I believe are reporting the sense information that was coming from the PM atrium lead when I was in Afib....basically a kind of "quiver rate". I should not have mixed apples and oranges.

I guess my situation makes sense if I take the 100 pulse I see and assume it is due to a 1/3, 1/4, or less conduction thru the AV node as the atriums are quivering. I see now I wrongly assumed that the 130 bpm that triggers the mode switch was an atrium rate. The mode switch at 130 is an actual pulse of 130.

So I guess what's happening is that my Afib is returning after the cardioversion albeit intermittently. I guess that means the cardioversion relief to normal sino rhythm did not last long; however, now at least the Afib is not constant, but comes in short episodes and has less impact on my pulse (100 vs 130+). Good news I guess if it doesn't get worse.....but it probably will :-).

Better monitoring will answer your questions

by Gemita - 2022-12-14 05:46:43

SGMFish, I am very sorry to hear that you have developed Atrial Fibrillation (AF).  Yes AF has many ugly faces.  Speed, rhythm, duration of episodes can all change rapidly which is why this arrhythmia is so hard for some of us to tolerate.  There is nothing regular about AF.   I often go in and out of AF and it can be very uncomfortable and cause instability.

Are your high heart rate episodes caused by AF you ask?  Perhaps, but of course there are many atrial tachy arrhythmias that may develop following an ablation or cardioversion and cause similar mayhem.

An external holter monitor will record and store all arrhythmia episodes whether at slow, normal or at fast speed, so the way to determine what is happening right now would be to ask for an external holter monitor or similar for say up to one week or longer (or keep recording with your Kardia Mobile and send these in to your doctors for analysis)?   Remember your pacemaker may be programmed only to store high heart rate arrhythmia episodes.  It doesn’t have space to store every short in and out arrhythmia episode.  My Medtronic mode switch for example only activates (switches from AAI-DDI mode) when my heart rate reaches 171 bpm for a certain number of beats.  Certain parameters, set up by my EP, have to be met for mode switch to activate and for a high heart rate arrhythmia episode to be recorded/stored on my pacemaker electrogram.

Short bursts of AFib are very normal with paroxsymal AF.  Doctors are not too worried about these if they stay short, the heart rate is well controlled and you are protected by an anticoagulant, if needed.  After a cardioversion and particularly after any ablation, I would expect the heart to be initially extremely irritated.  After my cardioversions my heart rate and rhythm for example were extremely volatile and I needed extra meds for several weeks.

You say Is my AS node maybe coming back to life occasionally?  Do you mean your atrial sinus node since I don’t think you have had an AV Node ablation?  Yes Sick Sinus Syndrome being an electrical disturbance can change over time.  It usually gets worse once it starts but of course it can fluctuate and sometimes improve too.  It sounds to me as though your atrial ablation has caused damage to your sinus node and triggered/unmasked other arrhythmias.  After an atrial ablation any fast electrical signals from the atria can still pass through the AV Node to push the ventricles if the ablation has not been 100% successful?  Maybe another ablation is in your future but before going down this route, you ideally need monitoring and more monitoring to answer your many questions.

Pacemaker interrogation

by Shementush - 2022-12-14 23:27:23

Isn't a pacemaker interrogation showing 24/7 monitoring of episodes more accurate than wearing a holter? Plus once I got my PM my insurance didn't approve a holter.

Afib?

by AgentX86 - 2022-12-15 01:11:25

"reporting the sense information that was coming from the PM atrium lead"

Yes, I understand that it's the atrial rate.  A ventricular rate of 300-500bpm would inhibit your writing skills.

But again, Afib doesn't have a high atrial rate.  Well, not that high.  It's an irregularly irregular beat (random, or more precisely, chaotic) but it's more like 85-150bpm.  The ventricles can usually keep up with AF.

AFL is what causes the atria to "quiver", or "flutter".  With those symptoms, I'm quite sure it's flutter.

PM vs Holter.  No, a PM can only record the one lead.  A holter gives a long-term 12-lead EKG. There is a lot of stuff that can't be seen on one lead (like flutter).  The flutter waveform is on lead-3, IIRC. Insurance companies will often do whatever they can to avoid costs.  If it was important, your EP could have appealed it, and won.  Insurance companies don't like to be accused of practicing medicine without a license.  The doctor has to push the issue, though.

After my seizure, my neurologist had me wear a turban sort of head thing wired for EEG and a monitor much like a Holter.  My insurance company refused to pay at first because it was "experimental".  The charge was $12K, which scared the s*** out of me.  I never got a bill but a month later I got a notice that my insurance company settled for $450 and paid it all. Whew! Insurance companies aren't all bad. Just most. 😐

Shementush

by Gemita - 2022-12-15 03:52:55

I agree with you, a pacemaker is still an excellent monitoring tool 24/7 and as technology continues to advance, so will the features and capacity of our future devices advance to hold ever increasing amounts of data to replace the burdensome and costly Holter monitor.  For the moment, however, the Holter monitor still has an important role to play in the detailed assessment of heart rate and rhythm disturbances.  I hope the following will help to explain this?

What is not always appreciated is that our doctors are able to programme our pacemaker devices to record exactly what they want to see, rejecting information which is not of interest.  Why?  Because our pacemakers have to perform primarily the function of pacing our hearts, doing all the usual housekeeping tasks of keeping us safe and there is a limit to the amount of data that can be stored at any one time.  Recording of data is not continuous but activated by default/programmed triggers, for example, high ventricular rates, meaning that absence of a pacemaker recording “cannot be directly translated into absence of an event”.

 Let us take an arrhythmia, for example.  A high rate arrhythmia of a certain duration will trigger a recording and its storage, whereas a slow heart rate of a shorter duration could well be rejected, depending on the parameters set up by our EP.   

Pacemakers can store episodes on patient demand, but the ‘event recorder’ feature has to be activated. The available memory for data storage differs between manufacturers and device types (eg, PM vs ICD), both in terms of overall size and in the way it can be reserved for different purposes (ie, atrial arrhythmia, ventricular arrhythmia, patient triggers). Moreover, a first-in first-out logic manages deletion of (older) stored data when the available memory is full, a critical issue in the case of delayed interrogations so some asymptomatic or minor events may well be missed. 

It has to be remembered too that depending on the number of leads that we have implanted and the site of implantation, this will affect what information can be stored.  My husband for example only has a single lead pacemaker (to his right ventricle) and his doctors are unable to give us detailed information from his pacemaker about his atrial arrhythmias, since he has no atrial lead.  A holter monitor, therefore will be needed in this instance.  The selection between the common two to three lead or the twelve lead Holter ECG monitoring depends mostly on what information is required.  If it is being used to monitor heart rate and its rhythm only then two to three leads may be sufficient.  If further information is required to establish the origin say of premature beats or other more serious arrhythmias, then a twelve-lead Holter electrocardiography may be needed.  

Before my pacemaker, I had an implanted monitor called a Reveal Linq monitor and my doctors left this in place after my pacemaker implant because they confirmed it had a better capacity to monitor my arrhythmias than my present pacemaker.

AgentX86

by sgmfish - 2022-12-19 19:02:59

I've been away, but I did want to respond (altho you'll probably never see this reply since this Forum does not push new posts to the top).

As I understand it, Afib often does produce pulses of 400, 500+ per minute *in the ariums*. I know I've seen 640+ bpm (upper limit they track) shown in the "device check" report I see every 3 months when they dump the data from my PM. Most pulses don't get thru the AV node of course, but before my cardioversion, my PM did a mode switch (DDD to DDI), and it takes a ventricular rate of 180 bpm to trigger that switch.

There is a ton of information in those PM device reports, but as you say, the data is limited to 2 sensing leads (but I think that's usually enough for most arrhythmia problems).

Gemita

by sgmfish - 2022-12-19 19:07:46

As I mentioned to AgentX86, you'll probably never see this, but I wanted to respond.

I see a ton of data in the device reports (often 12 to 18 pages long). Extensive summary data like histograms contain data from every beat (but summarized). I also getting EKG like traces but as you say they are limited to "events" like when the AMS system kicks in to do a mode switch.

In case anyone cares.....

by sgmfish - 2022-12-19 19:12:51

As long as I am doing replies.....

I am encouraged. As Gemita said, there is likely some instablity in the days and weeks after a cardioversion. Seems so in my case. For the last several days, I haven't measured a single "100+ bpm" episode. The PM is just sticking with the 55 bpm programmed base rate while I'm resting.....no more sudden and prolonged jumps to a higher rate.

I care and so do other members!

by Gemita - 2022-12-20 05:28:00

sgmfish, thank you for the update and for your valuable comments.  I am so pleased things are settling down for you and I hope this continues.  I can remember after my cardioversions (three in a row) my heart was extremely angry and I was very unstable.  Sometimes, perhaps you feel the same, the more we throw at our arrhythmias, the more we can expect difficult symptoms, at least until recovery has taken place.

With reference to your earlier comments, I agree our pacemakers do indeed have the capacity to store lots of data from our arrhythmias and these will be valuable to see things like % time we spend in an arrhythmia like AF for example, highest/lowest heart rate recorded, length of pauses ... and so on.

My clinic only gives me summary sheets of my pacemaker settings and downloads but when I had a Reveal Linq implant monitor, I requested copies of all my arrhythmia episodes (on disk) and it gave me everything I wanted to see.  I couldn't believe the long pauses I was getting (prior to pacemaker) and the incredibly high heart rates.  It shocked me but at least it told me what needed to be done.

I hope you have a very peaceful Christmas