Inching closer to right settings

Sinus node incompetence?

by AgentX86 - 2019-12-07 11:45:48

How is "sinus node incompetence" different than SSS or "chronotropic incomeptence"?  "Chronotropic incompetence" is a symptom and "SSS" is a cause. I'm not sure what "sinus nore incompetence" is, in fact.  Then I do a web search on it, it comes up with sites dedicated to SSS.  Can you describe it more?

The heart rate is dictated by the sinus node (or should be).  I'd think if that was your only problem you'd be paced something like AAIR. From:

<https://www.ncbi.nlm.nih.gov/pubmed/8458114>

"AAI pacing offers better hemodynamic characteristics than dual-chamber pacing and is the optimal mode for patients with sick sinus syndrome without AV conduction disorders." It goes on to say that DDD mode mode can be used with a long AV delay in case AV node dysfunction develops (1%-5% of patients).

sinus node incompetnence

by Keithwhelpley - 2019-12-07 14:10:38

Agent X86, I'm not sure what Sinus Node Incompetnence is except in the context of the way the phrase was delivered to me by docors. It may not be a diagnosis, but rather a description of something that doesn't fall within the boundaries of a diagnosis. I don't have either SSS or CI or AV block. But I do have a low resting heart rate and that's when theat phrase came up. Despite the low resting rate, my heart rate tracks up when it needs and goes down in a normal amount of time. When I'm completely still, watching television, my rate gets down to 54 bpm but when I sleep it will go below 45 bpm periodically. My upper chamber pacing is at 30%. Lower chamber is 4%.

 Though I originally was diagnosed with SSS and given a single chamber PM by a general cardiologist, it turned out via a subsequent heart study by an EP that I didn't have SSS afterall. But because I had experience VT (ventricular tachycardia) after the implant, they at least needed to give me an ICD. Unfortunately, I was never consulted about the new information (misdiagnosis) because it was discovered during my proceedure while I was out. The EP upgraded me to a dual chamber with an ICD and set the PM to DDDR to accommodate a misdiagnosis by the original doctor.

When I asked why THAT PM setting when I don't have the condition, he said I would have to ask the original doctor who put in the first device. But you are the specialist, I said.  I would hope that information gleened from your sophisticated heart study would trump an obervational diagnosis. Apparently not. 

This is where my utter confusion lives. I may have a condition, but as of yet, with four different EPs, I haven't been given an official diagnosis.  The common statements: "The (original) doctor must have seen something;" or "Your upper chamber is paced 30 % of the time. Something is going on;"

I don't mind having a PM. But I just want it either set for the condition I have or simply rolled back to purely data collection. Turning off Rate Response is another step toward that. 

BTW, what the original doctor saw was likely an electrolyte disturbance. This is a long story, but I've given up talking to EPs about that. The PM becomes like a spleen. If you're still alive and it's in you, then why change anything. Also, I believe cardiologits and EPs don't know these devices very well.

SSS and Chronotropic incompetence

by AgentX86 - 2019-12-07 15:06:20

Hi Keith, 

Yes, I don't know what I was thinking about with SSS and CI.  I had the same, except that my SSS was drug (sotalol) induced.  I also had asystoles, which was much more of an immediate issue.

VT makes the second lead, and DDD mode a lot more understandable, as does the fact that you don't have CI, makes the 'R' less obvious.

How do they confuse an electrolyte imbalance for SSS?  They didn't do blood tests before surgery?  That's pretty amazing.  I can see why you want to change doctors.  I probably woulf too.

RR

by MrTech - 2019-12-07 15:59:58

Hello again Keith

If I can clarify...

If a patient has a pacemaker implant because the sinus node wasn’t working properly (sinus Brady or sinus pauses) then often it’s ability to increase with activity doesn’t work well as well (blunted response). I’ve seen this many times - 

So you turn RR on. If you wait a few weeks before turning this on then you get the bonus (or evidence that it’s needed) to see the atrial histrograms. Your spread of heart rate (your ventricular rate should be identical to atrial histos if perfect 1:1 conduction all of the time) should look normal to what is expected given activity levels and age, with symptoms taken into account. If not - RR on. No harm trying even if you arnt sure based on histos. 

Anyway - DDDR for sinus node disease is fine IF the AV delays are long enough that you don’t V pace. You want 0% Vpace if you have no issues with your AV node.  If you have sinus node disease (and no AV node disease eg 1st, 2nd, 3rd degree block (CHB)  then often a pacemaker can be programmed AAIR-DDD or MVP (manufactures have similar algorithms that do same thing) which will minimise VPacing often in a better way. Eg they will even let a V beat drop before it paces to absolutely minimise VPacing. These algorhythms improve all the time. 

DDD is mainly for AV block with or without Sinus node disease. 100% accurate on this. - DDDR with sinus disease/chronotropic  incomp’ or DDD with NO sinus disease / chrono’ incom. 

Now, you mentioned that you have been told you have SSS as you have a low heart rate which is why the RR went on - But I get the impression this wasn’t confirmed. 

Now, this is the big thing - if it’s low because that’s ‘normal’ for you and your HR still rises and you don’t feel a limiting shortness of breath with exertion , then you may not need it on. 

If it’s low because there is some sinus node problem then maybe RR can help. It’s hard to know which - BUT if no serious bradycardia/pauses were noted and no obvious blunted HR is noted and no obvious shortness of breath, then there maybe no reason for it. 

Its really hard to know from the get-go. Medications can suppress HR but if you feel fine and no issues, then doctor may be happy with that.

How much you APace depends on what the lower rate is set to and what yours resting/sleep HR gets to. Just because you A pace - doesn’t mean you have a sinus node problem. 

RR will never replace a perfectly functioning sinus node but will is an excellent job if it doesn’t work at all or well enough. 

RR can be made v sensitive or less so to suit. 

Turning it off is a good idea IMO to test - Exercise, see how you feel, so this for weeks/months - Then when you go the clinic - look at the histograms. It will be pretty obvious if it was really needed or it least it should be to the professional looking at all this. 

hope this helps. 

Last thing though - IMO - Back and forwards to the clinic constantly tweaking the RR can become an annoying hobby. I.e try not too. 

Explain

by Keithwhelpley - 2019-12-07 16:16:53

AgentX86, explain how the DDD mode is more obvious. I don't understand considering I was programmed DDD the first go around with a single chamber PM.
 

They did do blood tests but my serum  magnesium was won the low borderline but not quite out. I discovered the magnesium problem after my VT. I gathered up my blood tests within the two month adventure and found each test my magnesium was lower than the last. As you may know serum levels and cardiac levels are different, but serum levels will show a trajectory. Once I discovered this I began ramping up magnesium intake and most of my symptoms disappeared. But cardiologist I've been to universally have discounted the magnesium theory, though they can't explain 

finally, what do you mean: the "R" less obvious?

DDD

by AgentX86 - 2019-12-07 20:48:12

You couldn't have had your pacemaker programmed with a single-chamber pacemaker.  The first two 'D's mean "dual pacing", or atrial + ventrical pacing and sensing.

My magnsium has been consistently low, too.  My EP and cardiologist told me to bring that up and kep hydrated and maybe my bigeminy PVCs would go away.  For the most part it worked (took a while). Potassium is even more critical and on both ends of the spectrum (too little or too much can be fatal).

'R' is less obvious because if you aren't chronotropically incompetent, why would you want to interfere with it?  A pacemaker will never be as good at regulating the heart's rate than a properly functioning SI node will. MrTech had some insight into this, though.  "Try and see if it works." Can't argue with that.  SSS with pauses would be a good example of where 'R' would be an advantage.  Set the "R" so it's always lower than the natural sinus rhythm and you get the best of both worlds.

I still don't get DDD with a perfectly functional AV node, though.  Only something like 1-5% of the people who have SSS will go on to have AV dysfunction.

Great points

by Keithwhelpley - 2019-12-07 22:17:03

You're so right about the Ds.  Feel stupid. I should have remembered that. Now magnesium should be supplemented because it's more difficult to get than potassium. And even if you have enough potassium, calcium and sodium, they aren't getting into heart cells without enough magnesium. Mag is the gatekeeper.  It took me six months to bring my mag up to good levels. I used an RBC blood test to track levels. More accurate than a blood test for Mag. I couldn't believe how I began to feel. My docs took me off metoprolol because magnesium was doing that job. When I stopped the drug, I began to feel even better. To get to that point I was tracking everything I ate and supplementing magnesium. Between the two, I took in between 800 and 1100 mg a day. I've since dropped my supplementation to 420 mg a day. Count yourself lucky your doctors take that seriously. None of mine would. 
 

Today has been the best I've felt in a very long time. As you know, Friday they turned off my rate response. I've been very active, like a new man. My wife is amazed at how much energy I've had. I'm knocking  on wood. But if this continues, I will titrate off flecainide and see what happens. I do have my ultimate  defense of VT in my ICD. An article published in 2016 by a cardiac journal cited sensitive rate response as a culprit for PM mediated ventricular tachycardia. I'm wondering if that has been my problem. Docs never go there because it implies they might have made a mistake. But consider this. When I had episodes of VT, they always happened in groups of three or four,  like I was in a loop. One would start. My ICD would pace me out. A few minutes later another one. And then another. And then nothing for the rest of the day. No triggers and usuallly when I'm my most relaxed. 
 

Thank you for sharing information. I hope I continue feeling good. I'm wondering if an activated rate response could some how contribute to unnecessary atrial pacing. A stretch, but there is so much we (doctors included) don't know about these devices and how they interact with our bodies. 

Magnesium

by AgentX86 - 2019-12-07 22:40:48

A good (in several ways ;-) source of magnesium is dark chocolate.  Most suppliments are really poor sources because they aren't well absorbed.  Magnesium Oxide is just about useless. I believe it's magnesium glycinate that's the best. 

Watch taking too much magnesium.  It can have, uh, embarrasing side effects.  Think "Milk of Magnesia".

Magnesiu

by Keithwhelpley - 2019-12-09 07:43:36

AgentX86, I haven't had those embarrasing side effects, but I know what you mean. I use Magesium Cytrate after trying others. My cardiologist uses Magnesium Malate and says he does for the absorption. Like everything cardiologists have said lately, I take his advice like I was taking it from any other person. The best thing is research. I agree about Oxide. 

Day four since my rate response was turned off. I feel better than I ever have. Had a great two hour easy bike ride and haven't felt as good since this all began. A dog charged at me while I rode and I was actually able to sprint away! AND I COULD RIDE HILLS.

I've been documenting my expereince because if anyone asks me, we have to be our health advocates. Another ugly truth is 99 percent of doctors think about us for the 15 or 20 minutes we are in front of them in their office or laid out in an acute situation. No thought is given inbetween, which is where answers come from. The uiniqueness of our situation is never considered. The intellectual curiosity that led our docs into the medical field doesn't seem to be availale to us. Is it dead? When my VTs started happening again, I asked my cardiologist if she would consider what I was telling her and that "she might learn something."  She said: I don't need to learn anyting from you. UUUGH. Her response was to say: I graduated from college. I have my degree, therefore I know all that could possibly be wrong with you. And if I can't stop what is happening, then there is nothing that can be done. 

I'm the one who told my doctor to turn off the Rate Response after research and interviews with experts. Against his and her best answer and better judgement they did. And guess what?! I rode two freeking miles and sprinted away from a dog. 

My late dad told me: Doctors aren't smarter than us, they just have been trained differently and posess skills.

Moving on

by Keithwhelpley - 2019-12-16 19:01:50

ar_vin, I felt the same way. This young cardiologist doesn't unerstand that every patient can teach you something. Most of us don't fit into a textbook description of a condition or we have multiple conditions that have to be navigated. For now, I do not have a general cardiologist. I'm relying on my EP. This two-year experience has taught me a lot and should have taught any doctor a lot more, who cared enouigh to learn. I an not afraid anymore to question openly anyting my cardiologist thinks about my heart. No one knows it better than me.