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Forum Name: Cardiology Treatment Modalities
|jensenholmes - Thu Sep 25, 2008 3:16 pm|
I'm 45 and an avid walker/hiker since 2001. I typically do 20+ miles per week over the course of 5-6 days. Slow heart rates run in my family but no one has ever had a pacemaker -- but they are not as active as I am. They are low 60's but I am 46 while sitting up in the dr's office. I am scheduled for a Holtzer to see how low I go in my sleep. I have had a stress test this past week and I maxed out at about 120 bpm going full tilt.
The main way this is affecting my life is that I do get weak/dizzy if I get up from being sedantary and, say, go up the stairs in my house. At the top of the stairs I am dizzy/muscles ache and I have to stop for a minute to recoup. I can live with this. But worse is that I am becoming more limited in my hiking. For some years I have had bouts where I will get faint/nauseous/clammy when climbing uphill and I have to stop and put my head between my knees. But these were intermittent and if I rested for a bit and I could go on and finish the hike. Recently it's become more severe because I moved to a hotter climate. If it is over, say 83 degrees out, and there is uphill, I get these crash symtoms. And I don't 'recover'. I feel better, get up, start again, and 20 steps later I'm back on the ground. I have had difficulty getting off the trail a few times in the past two months.
My cardiologist recommends a pacemaker. This seems extreme to me, and I'd like to get a second opinion. I really want to continue to be active. But on the other hand, I want to make sure I understand the medical risks of a pacemaker. And will it really be able to significantly improve my exercise capacity?
Thanks for your advise.
|John Kenyon, CNA - Thu Oct 02, 2008 7:52 pm|
Generally a pacemaker is required only if there is an actual block of the impulse from the sinus node where the heartbeat originates, and the lower chambers, the ventricles. It's rare for the sinus node to simply go slow at all times except in cases of sick sinus syndrome (SSS) where the heart goes alternately too slow and too fast/irregular. There is also a sinus node disease in which the node slowly deteriorates, but it is awfully rare to simply run too slow to function. If you had a 3rd degree (complete) heart block your rate would be in the 30s or perhaps even slower, and you wouldn't be able to do much at all. However, this is an unusual presentation of sinus bradycardia.
If it were me, I would want to make the decision based upon whether or not the problem were either a) progressive and/or b) life-threatening. Rates in the 40s are often seen in athletes (runners, swimmers), and some of them suffer, seemingly coincidentally, from cardioneurogenic syncope, an inability of the whole hemodynamic system, to keep the blood pressure up high enough to prevent occasional fainting. There are other, similar malfunctions within that system that can cause pressures to drop inappropriately, and it honestly seems to me that, absent an EKG to look at, you probably are having more problem with producing enough cardiac output, rather than the rate being too slow. This is probably a controversial issue, as a heart which will speed up to help compensate for a drop in blood pressure is the rule, and obviously yours is capable of getting into the 120s, at least, so it does respond.
What is sometimes done in cases like this is a minor surgical procedure called a vagotomy -- oddly something that used to be done for people with stomach ulcers but now considered "barbaric" for that purpose. The vagus nerve, which is one side of the autonomic nervous system's heart rate control mechanism, is then disabled (the breaks are off) and the heart tends to beat a little faster than normal rather than a little slower than normal. It isn't a reversible thing, but if there is no other pathology, such as a block in the electrical pathway, then this could be considered as an alternative to a pacemaker.
Don't get me wrong: I have nothing against pacemakers, but in a heart that's got its own, working electrical system, it does become somewhat problematic. I don't now that it's "extreme", and it might well improve your overall performance, but first I think hemodynamic control issues, such as cardioneurogenic syncope or at least incompetence, or baroreceptor failure (which is also often corrected using a device a lot like a pacemaker) should be ruled in or out first. The holter monitor will yield a certain amount of useful information, such as if your rate becomes dangerously slow during sleep.
You may simply be vagatonic (vagus nerve dominant) where some people are sympathomimetic (sympathetic nerve dominant and the rate faster than normal). There are probably other fixes to consider, assuming you don't suffer from any sort of heart block. I'd love to be able to see a copy of your EKG.
I hope this is helpful. If your doctor feels a pacemaker is the right solution, I would at least seek a second opinion. He may be right, but it seems as though more exploration should be done first.
Best of luck to you. Please stay in touch with us.
|jensenholmes - Mon Oct 06, 2008 9:35 am|
Thanks for your reply. It seems that you are right on the money. After looking at all my test results, my cardiologist has decided that my heart rate is not so low that she recommends a pace maker after all. My Holtzer showed my rate mostly in the 50's during the day and only dropping to the mid 40's in my sleep. My heart responded well to the stress test other than the fact that it might have gotten to 150 in another person as opposed to high 120's and I didn't get to 85%.
So she cannot explain my continued bouts of syncope. I did have low blood pressure on my most recent visit -- 100/70. She recommended that I eat a lot of salt and specifically a V8 a half hour before hiking to see if it helps. I'm recalling that my syncope has been particularly bad on a few occasions when I was on a diet (= low sodium). It's also much much worse when it's hot, which might also be blood pressure related. I'm to see an electro-rhythm specialist in Nov to see if he has further ideas on the faintiness. One other oddity was that the chamber of my heart that goes to the lungs had double pressure, which she said is sort of the opposite problem than 'low blood pressure' and would generally indicate asthma or some other reason why the lungs aren't able to process the blood normally.
It's a very real and very debilitating problem so hopefully the specialist can help figure it out. Your suggestions sounds very possible, esp the cardioneurogenic syncope. I'll take them with me.
|John Kenyon, CNA - Mon Oct 06, 2008 8:54 pm|
Hello again -
Good news! I'm glad to hear this. You're apparently a vagatonic type, and you may have some neurocardiogenic issue, which is usually not a big problem (and is manageable). An electrophysiologist is the exact right specialist for this sort of thing, and may be able to pin down more precisely the focus of the syncopal episodes so they can be prevented.
Salt is a very important thing in situations like this, so that's a good general suggestion. It can really make a difference in people whose pressure runs on the low side, and in those cases actually can safely be used to help bring things up to normal. Hopefully that will help.
Please stay in touch and let us know how things go with the EP specialist. Thanks for the update.
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