NSVT

Just for interest, I captured what I think is an occurrence of NSVT on my Kardia Mobile 6L a couple of days ago, which I've posted on the Member's Gallery.  I only knew that I had them from my last pacemaker interrogation, which showed one since the interrogation before that. Since I captured one, my assumption is that they're quite a bit more frequent than one every three months.  Or my pacemaker's detection algorithms are junk, which I've been suspecting for some time.

The two EKGs are identical.  The UI on the Member's Gallery isn't great so I ended up doing it twice. I didn't see a way to delete a copy so if you want to do that, Gemita, go ahead.

RIght before the NSVT episode is a PVC so they're probably related, which make sense.


5 Comments

It certainly looks as though it was fast enough to have triggered an 'Event' in your PM

by crustyg - 2023-07-19 12:04:21

Depending on what your PM classified as vent depolarisations there are either 4 or 5 in 800 ms (I think) which would fast enough to be classified as meeting the rate criteria for a vent-tachy episode.  Mine is set to 180BPM and this is well above that.

Happily it's a very short run, so it's possible that it wasn't long enough to 'count'.  My PM manual says that it will record Vent-tachy in response to 8 out of 10 fast beats - and obviously the rate is set by the EP-team (as above).  So your sequence wouldn't appear in the Event log on my device.

Not sure that helps, however!

NSVT (non sustained ventricular tachycardia)

by Gemita - 2023-07-19 14:46:41

Your Kardia Mobile ECG certainly tells me your heart is chaotic at the moment is how I would describe it.  I can make out the short episodes of VT and see the PVCs.  No wonder you are so symptomatic.  From your symptoms, I think you are probably getting more in the way of NSVT episodes, interspersed with your PVCs which are probably coming in fast now.

The Kardia Mobile has really coped well with your disturbances and I am impressed with the quality of the ECG produced.  I have yet to try out my Kardia Mobile on something significant, but I can see from your print that the 6 lead device is certainly going to be up to the job.

Not sure what your pacemaker VT monitor settings are but mine are as follows and I will post an EGM from my pacemaker of a NSVT episode in the Gallery in case it is of interest.  Now posted.  My rhythm strip looks regular and “controlled” though compared to yours AgentX86.  

Operation of VT Monitor My device detects a ventricular tachyarrhythmia episode when 16 consecutive sensed ventricular intervals are shorter than the programmed VT Monitor detection interval. The detected episode is classified as a VT Monitor episode if the ventricular rate is faster than the atrial rate. 

My Parameter Settings for VT Monitor:   Initial 16 (as per above), with a V. Interval of 400 ms, and a Detection Rate of more than 150 bpm. I had several events of around 8 seconds (more than 4 beats) of NSVT, maximum rate of 176 bpm.

Source of monitoring (upper/lower chambers)  

EGM1 (Atip to Aring) Sensitivity 0.3 mV - (now 0.15 mV)

EGM2 (RVtip to Rvring) (Sensitivity 0.9 mV) 

but my pre-arrhythmia EGM?3 seems to be OFF.  Maybe you could ask whether your pre-arrhythmia EGM is ON or could be turned ON, to see how you might slide into brief episodes of VT?

If you start getting more in the way of NSVT perhaps they will increase your sensitivity settings to capture more episodes but the source would seem to be from the PVCs and I really hope your true burden of PVCs/NSVT can be fully assessed and that you will get some respite from your arrhythmias soon AgentX86.  Thank you so much for sharing that excellent Kardia printout and please let us know what they find?

Kardia

by AgentX86 - 2023-07-19 22:48:12

I have another from today that has unstable periods for the whole minute.  There are seven very short episodes that look like the one I posted (but shorter, then there are other instabilities within a "normal" pulse. It's really ugly.  I didn't post it because it's eight pages long.

It's a good thing I have an appointment with my cardiologist and device tech (in the wrong order, go figure) next Wednesday.  I'll take these with me.

I'd seen similar things before but passed them off as electrical or contact noise. When I pressed harder, they went away.  Apparently, they just went away.

Good morning AgentX86

by Gemita - 2023-07-20 06:42:30

I know I have asked before and that you have had a successful AV Node ablation, but I suppose there is no chance that your Atrial Flutter or any other atrial tachy arrhythmia signal is able to get through to the ventricles to trigger disturbances?

With your increase in ventricular arrhythmias I would also want them to look again for other causes/changes in your heart condition since I know you have a history of heart disease.  Have you had a recent echo and were there any signs of cardiomyopathy or a fall in EF?

What symptoms are you getting during your rhythm disturbances when you do a Kardia ECG and have you kept a diary note of these to share with your doctors?  I hope you are still able to enjoy your early morning walks though and that you will remain safe whenever you are out alone.

AV node ablation

by AgentX86 - 2023-07-20 11:49:36

I don't think it would be reconnection of the AV node because the Bundle of His was ablated too.  It could happen but unlikely. It certainly doesn't look like flutter as it isn't regular.

I had an echocardiogram about six months ago, along with a PET scan, which weren't interesting.  My EF was still 55%. 

I had no symptoms other than PVCs.  I thought of that and am beginning to suspect my Kardia and external noise again.  I'll play with it more today, after I finish on the treadmill (Gerogia summers are too hot to be doing much outside).

You know you're wired when...

You have rhythm.

Member Quotes

The pacer systems are really very reliable. The main problem is the incompetent programming of them. If yours is working well for you, get on with life and enjoy it. You probably are more at risk of problems with a valve job than the pacer.