Reading the pacemaker report

SB = Sinus Bradycardia

by Gemita - 2023-06-16 13:36:12

Gotrhythm, I would understand that to mean Sinus Bradycardia.  It would appear you are still getting occasional drops into the 50 bpm zone, although I am uncertain what your lower rate setting is?  I wonder if you are getting atrial/ventricular ectopics and whether AAI pacing needs adjusting.  Are you getting any ventricular pacing at all?  I note your atrial pacing % is high at 88%.

Thanks Gemita

by Gotrhythm - 2023-06-16 14:01:12

Gemita. Actually, the AP is "improved" over previous interrogations. [tongue-in-cheek grin] For the last 6 or 7 years it has been 99%. I was, and probably still am, pacemaker dependent. 

For those who don't know, I put improved in quotes because the % you see is dependent on so many settings that it's not significant in itself. My first guess for the reason for the change is that the RR sensitivity was lowered.

Sinus bradycardia makes sense. Thanks, friend. I suspect it's happening a lot. Brain is not fuctioning at all well today. Wearing a Holter monitor.

Hope you get some answers from the Holter Monitor

by Gemita - 2023-06-16 15:06:10

My atrial pacing is also high, even without RR on at the moment.  I am being paced close to 100% but that figure is dependent as you say on so many factors, particularly on the lower rate setting.  Mine is set high at 70 bpm.  I have AAI pacing for my underlying rhythm (sinus bradycardia).  

Arrhythmias like AF and ectopics can certainly make me feel as though I am falling intermittently below the magic 70 bpm lower rate limit.  I know they tell us it cannot happen, but from monitoring my neck pulse manually and recording my symptoms, it certainly tells another story and I am not the only Pacemaker Club member who has confirmed this from his troublesome symptoms.

My brain in the unusual heat of early summer isn’t functioning at all well either.  I hope your heart rhythm settles soon and that the holter monitor will provide useful information.  Please do let us know when you receive the results.

Minor Symptoms

by Penguin - 2023-06-16 16:21:46

Hi GotRhythm, 

I can't shed any light on the drops to 50 bpm I'm afraid but I wondered what the 'minor symptoms' feel like? 

Was the previously diagnosed AVB (which seemed to go away) first or second degree (Mobitz II) block? Were there any AV delays programmed when your device was in DDDR mode to stop any v.pacing for 1st degree block?  If so this could have reduced v.pacing% to 0%. 

The only other thing I can think of in addition to Gemita's comments is whether or not you have a hysteresis programmed? Hystereses are programmed as a % and allow the pacemaker to 'wait' for your natural heart beat to kick in before the PM paces you. 

For example if your base rate was 60 bpm and a 10% hysteresis was programmed, the pacemaker would wait until your h/rate was 10% lower than 60 bpm e.g. 54 bpm before it paced you. 

A hysteresis is like an extra chance to see if your heart will beat on it's own. 

I would expect your techs to know if a hysteresis is programmed though.

Sorry if this isn't much help, but it's the only thing I can think of that hasn't been suggested already. 

Penguin "minor" symptoms

by Gotrhythm - 2023-06-17 14:55:37

How slippery the English language can be sometimes. Particularly when a lay person is attempting to speak to a medical person, both of whom believe they are speaking English, but may have different understanding of the same word.

I got into this issue with the pacemaker tech. I would hardly call a momentary lightheadness, presyncopal. Not for one minute did I think fainting was likely, or even close to likely. But he had a very off-on perspective. If a symptom was present, even in the slightest, barely detectable degree, it was there and that's what you call it.

The difference between minor and major symptoms in my lexicon, are that the minor symptoms are of such short duration (less than a second) that, if I notice them at all, my reaction is, "What was that?" It's gone almost before I realise it's happening and before I can even identify it. Things like light-headed, pre-syncopal feelings. Or a sudden feeling of tiredness while sitting still. Or sudden weakness in legs half-way up the stairs. Gone before I reach the landing.

The palpitations are also short lived and subtle. Just some different enought to be noticeable heart rhythm. Rarely identifiable as "okay, that was a PVC."

Just for contrast, in the past I have had PVCs so strong and violent, it felt like a fist to my breatbone, but from the inside. The pain was intense, and would force and involuntary "oof!" and my whole upper body would recoil.

As I'm sure you have experienced, the after-effects, feeling tired, dull, etc, lethargic,are longer lasting and cumulative. The more often the whatever happens, the more I feel tired, lethargic generally.

One of the symptoms which I am becoming more and convinced are arrythmia-related are sharp, sudden, stabbing pains in the temple. Again, lasting a second or less. I push the button on the Holter when I feel it. We'll see if there is any correlation.

Never heard of hysteresis. Feminist that I am, I have a knee jerk desire to reject it, but I will ask if it is programmed, or if it should be. Thanks for the input.

Gemita

by Gotrhythm - 2023-06-17 15:12:15

Interesting what you say about ectopics. And how you feel as if your heartrate has fallen.

On exactly one occasion, my symptoms lasted long enough to get a reading on the pulse/ox. It was 58. I hadn't felt enough PVCs to account for it, and since I "knew" [ha-ha] it was "impossible" with my pacemaker, I dismissed it as probably wrong. Now, I'm thinking that over.

I've never been diagnosed with ectopics before. I need to look it up as I have only the most general understanding of what they are.

The EKG report came in after I posted the interrogation report. It showed intermittant AV blocks are happening. But that wouldn't explain drops in atrial pacing, would it? Or would it?

Thanks for bringing ectopics to my attention. Thanks for being you.

Ectopics = PVCs and PACs

by Gemita - 2023-06-17 18:07:07

Gotrhythm I think you know a lot about ectopics already since they are also known as premature ventricular contractions (PVCs) which is a premature beat arising from an ectopic focus within the ventricles.  Also known as ventricular extrasystoles, ventricular premature beats, ventricular premature depolarisations.  Ectopics in the atria are as you know, known as premature atrial contractions (PACs).  

When doctors review device diagnostics such as electrograms or rate histograms they may see paced or sensed atrial or ventricular rates below the programmed Lower Rate Limit. Frequently, these “slow” rates are normal device function resulting from programmed features or standard sensing algorithms.  Atrial and/or ventricular rates below the Lower Rate Limit can be the result of over-sensing or caused by one of the following:

1. Rate Hysteresis (as mentioned by Penguin)

If the low pacing rates are the result of Rate Hysteresis and these low rates are unhelpful for a given patient, doctors may reduce the Hysteresis Offset to a lower value (to increase the rate) or by programming the Rate Hysteresis feature Off.

2. A-V conduction during paced A-V function  

A-V conduction can delay ventricular pacing. If a patient is paced at or near the Lower Rate Limit in both the atrium and the ventricle, and an atrial paced event is intrinsically conducted to the ventricle, it may cause the next V-V interval to be extended beyond the programmed Lower Rate Limit.

3. Premature Ventricular Contractions (PVCs)

PVCs can upset the timing of the PM, so there is a protective on/off detection safety mode.  A PVC can reset cycle timing and delay atrial pacing.  

I hope the above shows why we can experience an occasional drop in rate sometimes below the Lower Set Limit;  and to think I have always been told my pacemaker would never allow this to happen? 

Your intermittent AV Blocks may need settings adjustments and could explain a great deal Gotrhythm.  You are clearly AAI paced much of the time for sinus bradycardia.  Drops in atrial pacing rates (if that is what you are experiencing) could happen for any one of the 1-3 reasons above?

The sharp, stabbing pains in the temple mentioned in your comments to Penguin, I can relate to Gotrhythm.  I used to experience symptoms like this during fast arrhythmias, with sudden surges of blood flow to the brain causing intense flushing and pre-syncope/syncope.  My blood pressure would also surge out of control.  I was afraid of getting a stroke at the time I recall.  Temple pain can be serious and caused by many conditions, including temporal arteritis where the arteries become inflamed, so it needs to be reported.  

Ectopics = PACs + PVCs?

by AgentX86 - 2023-06-18 01:09:28

Like a PAC and PVC, a juntional rhythm is an ectopic. Ectopics are anything that is "other" (than normal pacing). Afib and flutter are then also ectopics.

It's interesting that, counting ventricular contractions as beats (normal definition), PVCs actually increase rate, though they fool monitors by completely missing beats, so read low. The PVC is shorter than a normal beat so more per second. Even if the AP is delayed by a PVC, the next pace will start after the set time.  The two beats (PVC + pace) are shorter than pace + pace. I can't really talk about PACs, AFib, or flutter and pacing because I don't do them.

If you get a Kardia, it's really interesting to wrap your head around some of these things. They make sense after some thought but they aren't obvious without seeing it.

AgentX86

by Gemita - 2023-06-18 05:20:37

My PACs and PVCs are commonly referred to as Ectopic beats and this is what I was referring to in my comments to Gotrhythm.  I was not referring to other arrhythmias that might fall under the same umbrella or be commonly triggered by fast Ectopics (as is my AFib after PACs or NSVT after PVCs), although it certainly feels as though they are all connected, since once one arrhythmia starts it often triggers or unmasks another.

I am actually quite surprised (and if I may say, somewhat relieved) by the realisation that the lower rate limit (LRL) when certain conditions are present, can actually be challenged.  To be told that my LRL is always close to 70 bpm and that the pacemaker won’t allow the LRL to drop by more than a few beats below this magic figure at any one time is clearly not always the case.  This needs further explanation for some of us and perhaps settings adjustments to help with symptoms of bradycardia which the pacemaker should be addressing.

Your comments about PVCs actually increasing rate makes a lot of sense in theory but from a symptom point of view, an ectopic beat (PAC or PVC) feels like a slowing, pausing, irregular heart beat that keeps dropping my heart rate well below the LRL at times.  I can see this is likely happening to other members too from their comments AND intermittent symptoms of sudden onset bradycardia again, a condition that should be easily treated with their pacemakers.

I have ordered a 6 lead Kardia mobile AgentX86.   Would like to interpret ECGs and understand my arrhythmias during symptomatic episodes, although I appreciate in the presence of a pacemaker and complex settings, ECGs may be harder to accurately assess.  I am impressed by how well you are doing though and I hope I can eventually have similar success

Gemita

by Gotrhythm - 2023-06-18 14:13:02

[Chuckles] You're right. I do know a lot about ectopics. I have, or have had, a whole alphabet of them. But just looking at the definition of the word, ectopic, I had pictured them as sort of like ghosts or machine gremlins that just randonly appear and disappear in different places. No pattern. Nothing anywhere near as definable and predictable (in it's own way) as PVCs and PACs.

I'm like the person who had been speaking in prose all the time--and never knew it.