Long term sinus tachycardia dangerous?

[twintrbl]

Hi everyone!

I was officially diagnosed with benign sinus tachycardia when I was 20, but have had it as long as I can remember. It was only when my PE teacher in college freaked out over a pulse rate of 200 after swimming a couple laps that I got sent to a cardiologist for an official diagnosis. After a treadmill test, I was told it was totally unimportant, and that even though my heart beat faster than normal, everything else about it was normal, so not to worry.

About 9 years ago, a different doctor was somewhat concerned and ordered another treadmill test - the results of which were exactly the same. "Your heart beats fast...The rhythm is normal... Intervals are normal... Everything is perfectly normal except it just beats faster than the average person." So other than being really annoying, I've pretty much ignored it.

Well, today I was diagnosed with mixed sleep apnea - both the "regular" obstructive kind and a few episodes of the "central" kind (caused by my brain forgetting to send the signals to my lungs to breathe). Since central apnea is usually caused by an underlying condition - often congestive heart failure - the doctor was somewhat concerned about my longstanding tachycardia.

He seemed to think that long term, lifelong tachycardia would eventually sort of "wear out" my heart, eventually causing congestive heart failure. I have no real signs of it at the moment (other than the central apnea), so he doesn't think that's the case right now. But he wants me to see a cardiologist anyway.

So my question is... is that long term sinus tachycardia really totally insignificant? Or can such long term tachycardia really "wear out" my heart? It sort of makes sense, but sort of doesn't. The doctor I saw was a pulmonologist, by the way, so I don't know his experience in the cardio field. I don't want to go to the hassle and expense of finding a cardiologist, getting an appointment, maybe being put on a treadmill again, only to hear the same thing I've already heard twice "It's insiginficant and unimportant."

BTW - my resting rate is usually around 95-100 bpm, almost *never* lower than the high 80's. Just sitting still and talking will put it up into the 130's, and exercising can easily put me in the 180's. (I'm 40 so that's pretty much the top.) I don't know if that's considered severe or pretty average for someone with sinus tachycardia. I've never met anyone else with it! And since the docs seemed to think it was about as important as having freckles, I thought it didn't matter.

Any advice?

[twintrbl]

Thanks! That's kind of what I thought about "wearing out". It would mean the more you exercised, the shorter your lifespan,and I'm pretty sure that's not the case. At least there's a lot of money being spent to convince us of the exact opposite! :)  

Then again, he did say that this was only a worry if you were *always* tachycardic for many years at a time. If you counted all the times my heart beat in 5 years, compared to a marathon runner who ran for 2 hours a day, even with the athlete's higher pulse for those two hours, the fact that his resting pulse is only half of mine the other 22 hours of the day probably offsets it. That's what I meant when I said it sort of makes sense, and sort of doesn't. I can see both.

The pulmonologist did suggest a beta blocker, but I'm not sure how well that would work for me, since in addition to being tachycardic/faster-than-average, I also have blood pressure that's usually a little lower than average. My normal is around 100/60 to 110/70 at worst, and I already get occasional "gray-outs" from standing up too fast (which I've been told many times is a result of low blood pressure). So anything that would lower it further might make it so that I couldn't get out of bed! From what I've read, low bp and fast pulse often go hand in hand. With low bp, the heart has to beat more often just to get the blood around - whereas if my bp was higher, it wouldn't *need* to beat as fast to circulate sufficiently. Which seems to me that the ultimate solution for me is simple - raise my bp!! Of course, even suggesting such a thing is blasphemy, so all I get is a pitying look from the doctor, who says, "We're not in the business of *raising* blood pressure. Just be glad yours isn't too high!"  Sigh.  

Might still be worth trying the BB anyway. If it lays me flat on my back, we can stop it, I guess.

Thanks again for the response!

[Jerry_NJ]

I don't know about "wearing" the heart out because of a higher HR.. if that was the case all athletes would die younger than non-athletes... hum maybe that is the case, but not from heart failure I'd bet.  

A resting HR below 100 is consider just fast, not tachycardia as I understand it.  I think the problem with a higher resting HR is your system demands it and there is less "room" between resting a cardio HR limits, as you've already noted... you run out of safe heart rate for exercise.

Has anyone said "Beta Blocker" to you?  If your blood pressure is about normal you should be able to tolerate a low dose BB to bring you HR down a few beats.  That's how I see it, I think you'd be better off if you could get you resting HR below 80, even if it takes some medication help.  Low dose BB, in my view 50 mg a day or less, usually has minimal negative side effects, but that depends on the individual...some can't take it at all.   A BB may also raise issues with apnea... your doctor will know.  I think your primary care doctor may be willing to write a prescription for a generic (lower cost) BB so you can try it.