Trying to Understand my Heath Block

doctors vary

by Tracey_E - 2017-11-22 09:26:09

Some doctors are considerably more conservative than others. Some of them don't have much experience with active patients so they tend to err on the side of caution. They are in the minority and I believe with those doctors it's more knee jerk than founded in fact.  There have been a few isolated cases of activity causing lead issues but not many. As long as the device isn't right under the collarbone where the leads can get pinched, you should be able to do what you want. I do Crossfit, with my doctor's permission, have been doing it regularly for 6 years now. Running, rowing, barbells, pull ups, push ups. Shoulder presses, jerks, snatches, deadlifts. I don't hold back at all and have never had a problem. Use common sense and start slowly, stop if it doesn't feel right, but you should be able to test the waters. I don't know much about valves but as long as the valves aren't the problem, the pacemaker shouldn't be either. 

With heart block, the  heart has an intrinsic underlying rhythm, which means if the pacer for some reason stopped pacing (which does NOT happen!!!), we'd feel like crap but we would be ok. The ventricles would be beating, just not in sync with the atria and probably not very fast. 

Thanks Tracy!

by alatos - 2017-11-22 12:32:48

Thank you Tracy. The underlying rhythm is something I was already aware of, but my pacemaker doctor led me to believe my heart might not have an underlying rhythm. I mean, he flat out told me that. He took my pacemaker down to pacing 30bpm, and said he could shut it off completely if I wanted to see if there was an underlying rhythm, but I passed on that. I felt weird enough at 30bpm. After looking at the pacemaker data, he also said my my lower chamber is paced 100% of the time. It's all confusing, because I read online about the underlying rhythm as if it is a guaranteed thing, and then he says it might not be. What if there is no underlying rhythm and the lead breaks? 

Heart block and pacemakers

by LondonAndy - 2017-11-22 14:12:28

Hi Alatos

I have CHB too as a result of surgical complication when they fitted my mechanical aortic valve 3 years ago.  At my most recent annual pacemaker checkup, in October, they told me that I did have "a few random underlying beats", which I think was a change from previous checkups, though I didn't think to explicitly ask a question about this.  I have assumed that this is a small improvement on previous annual checks, but if so it was certainly not sufficient to change pacemaker settings to reduce from being 100% paced.  So my current understanding is that (a) some recovery from CHB is possible, but (b) my underlying beats don't currently amount to much that would be useful in the extremely unlikely event of the pacemaker failing to pace me for whatever reason.  I will ask more next year, but until then it won't affect my day-to-day attitude, which is to carry on doing whatever I want, including some lifting of weights.

underlying rate

by Tracey_E - 2017-11-22 16:02:28

It's normal for those of us with CHB to pace every beat. If your block is from recent surgery, it can and probably will somewhat improve over time. Mine is from congenital, not from surgery. When they checked, my underlying rate has been anywhere from under 30 to 60. When they test it, they won't go under 30 or leave it off for more than a few seconds. Your rate without could be under 30 or it could just take more than a few seconds for it to start beating on its own. It's very rare to have absolutely no underlying rate, but there are limits to what they will test so nothing when they test doesn't necessarily mean nothing. 

,more about how we pace

by Tracey_E - 2017-11-22 16:08:25

With CHB, the pacer is playing follow the leader.  It watches every time the atria beats and gives the ventricles a fraction of a second to beat on their own, if they don't it kicks in with a paced beat,. We pace every (or nearly every) beat because the ventricles, when they do beat, rarely do it in sync with the atria because they aren't getting the signal. That's the block- the electrical signal from atria to ventricle. So if our underlying rate was 30, we'd still pace every beat, does that make sense? The pacer is never going to wait long enough for the ventricles to wake up and get a clue, it's always going to pace nearly every beat. 

response

by alatos - 2017-11-22 16:16:58

Thanks to both of you. I do understand the concept behind the block, pacing, underlying beat, etc. All that seems pretty straightforward to me. My question was more specifically whether or not "underlying beat" is a guarantee, and, if it isn't, what happens then in the event of a lead break? But you both definitely helped to clarify that for me. I really appreciate it so much! 

underlying rate

by Tracey_E - 2017-11-24 10:19:19

There is no guarantee, no, but it would be very very rare for the  heart to not kick in with some sort of beat. 

When leads go bad they don't typically stop pacing. If they were to dislodge, it would have been in the first few days. Now, you've got scar tissue holding it in place. After the first year it's held in so well it takes a special laser to get it out. I've heard of a few random cases of leads being sheared off, one was a car accident. More common, the insulation ruptures so it takes more juice to get the signal through but they don't stop pacing. I had that happen to one of my leads after 15 years, the ventricular so the one I depend on. We left it alone and monitored for another 5 years, then when the battery needed replaced did it all at once. 

So I guess I'm saying while there's no guarantee the ventricular lead can't be damaged to the point it doesn't pace, and there's no guarantee you don't have some sort of underlying rate, the odds of both happening? Nothing to lose sleep over. 

Okay, now that makes sense

by alatos - 2017-11-24 17:53:11

That is exactly what I was wondering, Tracey. Thank you so much! That really does help put my mind at ease! :)