Automatic mode switching (AMS) in atrial fibrillation

AMS - automatic mode switch

by Gemita - 2022-08-22 01:14:58

Stache, AMS is the automatic switching of pacemaker modes to prevent the tracking of an atrial tachyarrhythmia for the duration of the arrhythmia.  The mode automatically switches back to its former mode setting at cessation of the atrial tachy arrhythmia.  This pacemaker function prevents the fast atrial rate being picked up by atrial sensing and then pushing the ventricles too fast which would of course be dangerous, especially if the arrhythmia was long lasting.  So AMS is like a safety device.  Mode switch will also help to control our symptoms which can only be a good thing.

Should you be concerned?  Yes and no.  Yes in that any increase in mode switching tells your doctors that your atrial tachy arrhythmias are becoming more frequent, that your heart rates during episodes have exceeded the parameters set by your EP (say above 165 bpm) to trigger a mode switch.  This would suggest that your heart rate and arrhythmia control may need to be better managed.  No in that if you have frequent, short bursts of atrial tachy arrhythmias like me, your doctor might not be too concerned.  While short in and out episodes can be destabilising at times, because episodes start and stop on their own, without intervention, doctors may not be too concerned.   For example, my % time in AF continues to be extremely low despite all my mode switches and has been like this for years which does surprise me because AF usually progresses.  I am presently going through an increase in my AF though, but hopefully it is only temporary.

Clearly Stache you need to assess what this means for you personally in view of you heart condition.  I see you have stents for coronary heart disease.  Your doctors will obviously want any high atrial rates to be well controlled as well as controlling the duration you are actually in an atrial tachyarrhythmia.  But try not to worry.  That will only cause stress and make any palpitations worse.  Your doctors will know how best to manage this.  My last 12 month AMS count was down to around 1000 (from 2500+ previously) so I know my AF is being controlled, the little pest.

What are your symptoms Stache?  Hopefully they are minimal

Symptoms

by Stache - 2022-08-22 21:34:16

My symptoms really started after the doctor took me off 

A lot of the symptoms started after the doctor took me off Pradaxa blood thinner medicine that lowers the chance of blood clots, Prinivil ACE inhibitor, and Plavix.  I am still taking two other meds daily.  Seems my blood is back to normal and can clot now, but I have fatigue now that I didn’t have while taking all the meds.  I am always hungry and drink a lot of water, and my eyes get a little blurry and I see sparkles now and then.  I don’t get dizzy as I used to on the blood thinners.  I do feel hot when it is not but this is California and it has been HOT here 

I walk for one hour every morning and a couple times a week ride my bicycle after walking for 2 hours.

Strange as it sounds I can feel my heart flutter and the shocks my pacer puts out.  My blood pressure is constant as I check it morning and night and record it since my cardiac arrest 3rd degree 02/08/2021.

Follow-Up

by Stache - 2022-08-25 21:32:48

Today I had a very lengthy conversation with my cardiologist (the squeaky wheel gets the oil), about the AMS and my atrial fibrillation.  I have been assured the pacer AMS is doing exactly what it was designed to do in my case and yes I have had some severe AFib events that lasted for many hours back in March while I was taking Pradaxa at the time.  In June my Pradaxa prescription ran out and I was taken off Pradaxa.  However, today the cardiologist put me back on Pradaxa as the AFib sessions are still happening but not as bad as in March.

I have spent the day reading AFib studies and have concluded vitamin C 500 mg twice a day is better at reducing AFib as an alternative to other drugs.  I did pick up my prescription of Pradaxa today but it does have a lot of side effects for now I am willing to go back on Pradaxa until my AFib calms down as it will never go away.

I was told I am considered a high-risk patient and have been placed on the 24/7 tracking program another reason Pradaxa was prescribed.  The good news is all of my blood tests came back with great results today.  My everyday exercise plan has paid off of walking for 1 hour every morning rain or shine mostly shine here in Northern California and riding my bicycle 2 to 3-times a week on 20 to 40-kilo rides.  At this point, there isn’t much I can do but keep up my exercise, stay on my diet, and just hope for the best.

Thank you for the updates

by Gemita - 2022-08-26 01:45:06

Stache, I am a Vitamin C believer too (taken in non acidic form as Magnesium Ascorbate or Calcium Ascorbate).  Cannot take Ascorbic Acid because of bowel distress.

Pradaxa?  Not sure of the difference in cost where you are but Eliquis anticoagulant might be a safer option.  Many take Pradaxa but Eliquis can be easier to tolerate, with fewer side effects and potential risks. 

Providing heart rate when in AF is well controlled and that we are protected from the risk of having an AF related stroke by taking an anticoagulant, my doctors are not overly concerned.  What counts too are "symptoms".  Difficult symptoms can help determine whether or not to try to better manage AF by having an ablation.  Like you I am trying to manage my condition by lifestyle changes although you sound as though you are better at exercising than I.