Response rate settings

Hi everyone, I would like an opinion on this.  I was in a serious motor scooter accident almost two years ago.  24 days in hospital, right leg broken in four places, brain injury, the list goes on.  Eight months later, I passed out while singing in a choir concert.  Started seeing a cardiologist and had all tests including electrophysiology, could find nothing.  They implanted a loop recorder with hopes to catch something.  Four months later, I almost passed out at work 30 min after walking 3.5 miles there.  The recorder caught my HR drop from 60 to 30 in 10 seconds and hovered there for 10 min.  Then back to normal.  Diagnosed with Sick Sinus Syndrome, pacer installed.  Originally set at 50 bpm day, 40 night.  Two weeks later, check up reported 8% assistance.  I talked doc into lowering to 45/35, next report 0.1% assistance.  It was pushing when I was at rest unnecessarily.  All was ok for about five months.  Rode bike to work last November one particular day.  Within 10 min arrival I had an episode while sitting and passed out for a few seconds.  I asked them to bring BP device.  It showed HR at 45.  I told them pacer was carrying me and in a few minutes I recovered.  Problem was that having just exerted myself plus having been cold, I probably needed 90 or so.  The pacer did its job, just not fast enough for the situation.  Four months later, I call Medtronic to suggest programming an algorithm to look at 5 min rolling average HR and kick in if it sees plummet, rather than just wait until a minimum setting.  Customer rep says, "there is a rate change algorithm in there already, it's just not turned on."  I can't understand why I wasn't informed about that capability when installed.  Anyway, I see cardiologist in 10 days to implement it.  I did a little test of my own a few days ago to see my 'normal' HR drop after exertion.  I rode my bicycle to town & back, then up a hill, then stopped, sat down, and recorded HR every 30 seconds for 6 min.  It started at 166.  The fastest 30 second increment drop was 32.  So, when my last June event happened, my HR dropped almost three times faster than my fastest drop normally.  So, I would say that if the time window gets set at 5 seconds and the drop rate max is 10 beats in that timeframe, that would easily permit normal conditions but quickly come into play when I have an actual event.  It could rev me up to 100 for a minute, then relax and see how I respond.  If I fall too quickly, do it again until I stop descending too quickly, then relax.  That would carry me through the episode without letting me get near syncope.  I'm miffed that I just learned about this feature, but so far I've had only one event, and it was very minor.  If my natural HR drop was 5 beats in 5 seconds, and my event rate was 15 beats in 5 seconds, then 10 in 5 seconds should keep the pacer from working when it doesn't need to but definitely when it does need to.  Opinions?

15 Comments

minimizing pacing

by Tracey_E - 2019-03-31 14:17:06

My opinion is don't be so afraid of pacing. It's good to not pace too much, however going to extremes to minimize pacing defeats the purpose of why you have it. There is no amount of pacing that's considered ideal, the important thing is our body is getting the oxygen it needs when it needs it so we feel good. Many of us pace 100% and have no ill effects. A normal heart rate is 60.  If your rate is 35 at night you aren't going to feel as good during the day than if it was 60 or 50 at night. You can't feel it directly but the effects are there. 

They can adjust the settings so that the pacer doesn't let you drop (rate drop). That's unrelated to kicking in when your rate gets too low (minimum rate), or when it doesn't go up quickly enough on exertion (rate response). It's normal to take a few tries to get the right balance. They like to make changes in small increments, try it out, adjust again as needed. 

Response rate settings

by marcdeluca - 2019-03-31 14:27:48

My guess is that had my pacer still been set at 50, it probably wouldn't have carried me through.  The rate algorithm implements variables to work better under various circumstances.  I never feel tired at my normal rates, and when they set it from 50 to 45, it lengthened the battery life by seven years!  But when I have an episode, I really need its help.  

Rate response settings

by AgentX86 - 2019-04-01 22:07:23

Lengthened battery life from what to what?  f you set the pacing to 0bpm, you'll never need to change the battery.

Tracy is right.  Don't be afraid of pacing.  If you pass out at the wrong time, you could be killed.  You have the pacemaker for a reason.  Use it.

Rate response settings

by marcdeluca - 2019-04-01 22:38:10

I am not opposed to pacing.  I wouldn't have this thing if I was.  However, I would like to be paced when I need it and not when I don't.  If an algorithm that is already in it can be implemented to do just that, then I am going to put it to work pronto.  I don't believe that the current settings work for me.  They don't cover variables that I have.

Rate response settings

by AgentX86 - 2019-04-01 22:58:43

You're asking for a lot from your pacemaker and those tuning it.  It's not an easy process and you may be paying through the nose to get everything set just so. 

Of course, there is nothing wrong with having your pacemaker optimized for you but minimum settings that are too low to sustain a healthy life isn't smart.  If you're passing out, or even coming anywhere close, you're playing with fire. 

Response rate settings

by marcdeluca - 2019-04-01 23:19:30

I have had one event since the pacer was put in last June. That event revealed that the settings aren't adequate.  I am not going to just raise the minimum setting and be satisfied to have this thing pushing me 50% of the time when I need it 15 minutes a year.  I studied the program and figured out what the parameters need to be set to.  I will see the cardiologist late next week and we will implement them.  I'm disappointed that it took this long for me to find out what it can do, but at least this capability fits my condition spot on.  My episodes are very infrequent; I can't expect this to be dialed in right away.  It took 14 months just to identify the condition.

insurance

by ROBO Pop - 2019-04-01 23:38:59

May I suggest you consider getting malpractice insurance. Sounds like you should sue yourself for malpractice.

In spite of your belief, you aren't qualified to determine programming settings on your device, but if you continue to insist they change settings per your instructions then blame yourself for the poor results

Amazing, just amazing

by AgentX86 - 2019-04-02 08:12:58

You only need to pass out once, at the wrong time, to die. Your choice.

An apparent misunderstanding

by marcdeluca - 2019-04-02 08:54:36

It would appear that I am stone stupid to want this pacer to work better than what the 'expert' doctor set things at.  I am an engineer and this algorithm isn't that hard to dial in.  It will continue to have the minimum limit control that it currently has with the rate change response added to it.  I can assure you that I really don't want to repeat the accident that started this whole process.  Enough said.

how often you need it

by Tracey_E - 2019-04-02 10:47:20

My point was, it sounds like maybe you need it more than just the episodes you've described and perhaps it's good that it's pacing you other times. You can get by with a low heart rate, but you won't thrive because your organs are being starved of oxygen. There is a reason why anything under 60 bpm is considered bradycardia. 

Apparently

by AgentX86 - 2019-04-02 10:56:55

You're not reading well. No one said that you shouldn't have your pacemaker performance optimized. We ARE saying that optimizing for pacing percentage is plain silly, particularly when you're in danger of blackouts. They're nothing to trifle with. They can kill you.

We're also saying that playing doctor is just stupid. I don't give a crap if you think you're God's gift to engineering. You are NOT a doctor, much less an electrophysiologist.

BTW, I are an enjuneer, too, and can read the documents. I'm not about to argue PM settings with my EP, even if I don't like some. Others, we work on.

I'll let you get on with your attempted suicide now.

Fainting

by Weezie69 - 2019-04-02 14:39:19

Have you ever had a tilt-table test to rule out Neurally-mediated hypotension? BP drops and you faint.

Tilt table

by marcdeluca - 2019-04-02 15:35:59

The tilt table test was one of the first ones done trying to diagnose this.  It was 15 minutes horizontal, 45 standing, BP every 3 minutes the whole time.  Not the slightest response.  My events are many months apart, and last a few minutes, then I'm like it never happened.  Very difficult to diagnose because it's so infrequent.  Took 14 months for them to nail down.

What Weezie69 said

by Gotrhythm - 2019-04-02 17:34:08

It's possible to have SSS and neurocardiogenic syncope at the same time. I do. A lot of what you complain of could be explained by NCS episodes.

You may think the pacemaker is kicking in when you don't need it, or not kicking in fast enough when you do, but if you have NCS, the real cause of your symptoms isn't what the pacemaker is doing or not doing. The cause is fluctuations in hr and bp due to NCS.

When NCS causes your hr to drop even a little bit, the pacemaker will kick in. But even when the pacemaker is supplying beats exactly as it should, it can't keep your blood pressure from dropping and you can still faint.

 

Pacer programmed today

by marcdeluca - 2019-04-12 18:42:38

I saw my doc today, and the rate response function is now on.  It is programmed to engage if HR drops more than 15 bpm in a 10 second window.  It will pace at 90 bpm for one minute, then stop and observe.  If I'm still having an episode, it will repeat the one minute cycle until I respond properly.  The minimum limit is all set the same as before.  It will be very interesting to see how noticeable this will be, if at all.  It will log an event when it occurs, so if somehow I don't know it the hospital will.  My last event was over five months ago, so I may be nearing the next one.  If this all works as expected, it will be like tailor made for me.  It is amazing to me how my natural pacer can work so perfectly for months on end, then so badly for a few minutes, then perfectly again for many months.  

You know you're wired when...

Your favorite poem is “Ode to a Cardiac Node”.

Member Quotes

Yesterday was my first day mountain biking after my implant. I wiped out several times and everything is fine. There are sports after pacemakers!