need advice

I am a 71 y/o retired doc, lifelong endurance athlete, with aortic valve replacements X 2 in 1992 and 1999. Doing well until got endocarditis last fall and started into atrial flutter/tachycardia and got a Medtronic ADDR01 pm 3 weeks ago, along with coumadin. I am doing well and started walking almost immediately. It became clear quickly that this pm which has an accelerometer only will probably not meet my physiologic desires. It appears incapable of responding to any change in exercise demands that are not accompanied by an increase in foot strike pace. e.g., walking steep uphills will not produce any different HR than the same pace on the level or downhill. I understand that the Boston Scientific has a model with a minute ventilation sensor and that Biotronic has one with a so-called closed-loop-stimulation, both of which seem superior, at least in principle and according to some published papers, in responding to actual physiologic needs. Has anyone been through this dilemma and have any advice either on how to best accomodate to the Medtronic or experience with either of the other pm's? Thanks.

8 Comments

I am no expert

by BillMFl - 2014-01-28 01:01:45

But my first PM, a Guidant, had an accelerometer function that so hyper sensitive that any sudden quick movement would immediately bump my HR to 110 bpm even if I was sitting down. The bump up would be brief if I stayed at rest. The PM rep turned it off for me and said it was ment for patients with weak hearts to give them a boost. I didn't need it and it drove me nuts until it was turned off. Hopefully they have improved that function. I think Guidant is now merged with Boston Scientific. As I recall they had many issues. My Medtronic does not cause me any problems like that.

Note to Inga

by Moner - 2014-01-28 03:01:18

Hi Inga,

Once again Inga you really enlighten me everytime I read one of your responses, even if it's not something that applies to me.

It's always good to learn more and more about the pacemaker world.

Moner
>^..^<

Rate response

by golden_snitch - 2014-01-28 03:01:39

Hi Dennis!

Allow me one question first: Do you need the rate response because your atria are in afib/atachy all the time, your AV-node has been ablated, and now the ventricular pacer lead needs to adjust your heart rate to your level of activity? Or are you a slow afibber who ends up with bradycardia when in afib? In case your AV-node has not been ablated and you have a lot of tachy in your atria, I am not sure that the pacer's rate response can actually work. It's likely that the pacer is simply overtaken by the tachy. Usually, only people with sinus node issues need the rate response sensor. Heart block patients don't, unless they have persistent/permanent afib.

Among all the accelerometers on the market, I have only heard the best about the Medtronic accelerometer. Medtronic has about 9 rate response parameters that can be optimized either automatically or manually. So, there is a lot of room for optimization, which I'm pretty sure you have not yet exhausted in the three weeks that you have your device. However, as all accelerometers, the Medtronic one has its limitations because it needs upper body movement to sense activity. Consequently, riding your bike will be difficult, but walking, running, swimming should be fine. So, my first suggestion is that you give your Medtronic device and your cardio some time to optimize your rate response settings. That should be done using a treadmill, probably also a holter monitor, and Medtronic pacers also have an exercise test that the cardio can activate. When activated this test runs for 15 minutes so that you can make a quick walk, run up and down some stairs etc., and then afterwards the pacer shows what the RR has done, what your own rhythm has done, and then the cardio can optimize settings accordingly.

If you cannot get the Medtronic rate response optimized so that it fit your needs, a dual-sensor rate response with accelerometer and minute ventilation or a CLS sensor might be better for you. From my personal experience I can say that I have had accelerometer plus minute ventilation for many years - first in my old Medtronic Kappa 401, then in my Sorin Reply -, and was doing well with this combination. It did need quite a lot of fine tuning, too, but then worked well. All the heart rhythm specialists I know say it's the best rate response sensor with the most physiologic response.

I now have a Biotronik Evia with CLS. This is because the minute ventilation sensor in my Sorin Reply kind of quit its job when I was switched to epicardial pacing; this sensor does not work with epi-leads. So, I was left with the Sorin accelerometer only, and that turned out to not fit my needs at all (unlike Medtronic pacers, it had very limited RR optimization options).

My first days with CLS were rough. I was going into tachycardia and actually up to my max programmed rate of 140bpm basically whenever I moved. Fortunately, the automatic optimization has done a pretty good job in the past two weeks, so now I'm getting much more appropriate heart rates. I no longer go for walks with 140bpm, but am down to somewhere between 90-120. Also, I can move around my apartment without going into tachy all the time. But it's only been two weeks, and I have not really exercised, yet, due to soreness and the muscle (subpectoral implant) needing time to heal. So, for now I cannot tell you how CLS responds to running or cycling or anything like that. It is doing a good job at the moment, and I'm actually surprised how well the automatic optimization has worked, but with regards to "real" exercising I have no experiences, yet.

I have read, I believe, all studies that have been published about CLS. And from those studies I understand that CLS does indeed respond to mental stress, but when it comes to physical exercise I have not found any data that would support superiority of CLS to dual-sensor RR or a good accelerometer. The studies have often concentrated on CLS response to mental stress, because this is what's unique in rate response sensor. CLS should however be better for physical exercise, too, since it does not need upper body movement to sense activity, and therefore allows for a greater variety of sports. But I really have no data on this and no personal experience just now.

So, first of all you need to make sure that with your condition you actually need the rate response. Then, if that is the case, I'd suggest that you try to get your Medtronic accelerometer optimized. I hope you have a good cardio who's willing to invest some time into the fine tuning. If not, call Medtronic and ask them, if they have a cardio somewhere in your area with whom they work well together, and who might be willing to optimize your settings. You have had this pacer for three weeks only, so I think it's way too early to come to the conclusion that the accelerometer doesn't work for you. If all the fine tuning doesn't help, and the bad rate response limits your activities too much, then consider dual-sensor RR or CLS.

Hope this helps a bit.
Best wishes
Inga

Interesting !

by IAN MC - 2014-01-28 05:01:51

I wonder is there anyone on here who really finds their Rate Response function to be as good as the real thing ?

Can they honestly say that it makes their heart respond in EXACTLY the same way as it did before they became chronotropically incompetent ? I get the impression that whether you've got an accelerometer or minute ventilation you still don't get a totally normal response to exercise.

I hope I am wrong and that the answer is having perfect optimisation of the settings.

Like you Dennis, I have been a lifelong runner and exercise nut and I, too, have a Medtronic ADDR01 . My experience was one of marginal disappointment at how little difference the RR function made. On balance I function better without it but this is under continual review !

Best of luck and let us know the good news when you get it right !

Ian

Ian...

by golden_snitch - 2014-01-28 06:01:10

NO rate response sensor is as good as a perfectly functioning sinus node. I usually tell everyone who depends on a pacer's rate response that they should not have this expectation, because then there will always be disappointment and frustration. You gotta make compromises, if you rely on the pacer's rate response function. If the CLS works well, it should come somewhere close to a properly working SA node, but the other sensors definitely don't. Accelerometer and minute ventilation are not able to respond to anything but physical exercise, while the sinus node also covers excitement, nervousness, panic, and all other types of mental stress.

Inga

Doc, you need...

by donr - 2014-01-28 12:01:08

...the Golden_Snitch. Harry Potter will awaken her in Berlin & deposit her in your thread in the AM when you awaken.

She knows all about PM's & their RR functions. She has special needs when itr comes the RR.

Don

Back to you

by RDD - 2014-01-28 12:01:17

Thanks, Don....funny,just before reading your comment,I had private-messaged Golden_Snitch (aka Inga) about this subject as I was quite impressed with her apparent knowledge in this forum. Best to you.
Dennis

note to Inga

by Jackcouo - 2014-02-02 02:02:38

I am really impressed with the information you have given here, maybe you can help me also. I'm a 74 year old avid cyclist (mostly mountain bike). Long term persistent afib, 4 ablations and one minnie maze, now in nsr with no meds.
I got my first pacer a little over a year ago, (for bradycardia) a Medtronics Revo MRI RVDR01, its upper limit was 150bpm. When riding under heavy exertion I would reach the upper limit and I would just hit the wall, gasping for air and get weak in the legs. So my cardiologist put me on the tread mill and confirmed that the pacer was limiting my performance.
Two months ago he replaced the old pacer with the newest Medtronics pacer, Advisa DR MRI SureScan, A2DR01.
This pacer has a top rate of 210bpm and many more adjustments. Now my heart goes to 170bpm under heavy exercise and just faltens out and stays there. I'm going in next week for more fine tuning.
Here is my question: Before I had a pacer my max heart rate while riding was in the mid 130's and averaged around 110/120. When I got my first pacer my max went up to 150 (the upper limit of the pacer) and my average during a ride was 130 to140. Now with the new pacer my max is 170 with an average in the 150's. It seems like the pacers change the normal function of my heart, is this possible? I'm not sure you can answer this question but any information on this would be appreciated
Jackcoul.

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You participate in the Pacer Olympics.

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