Seriously, when does a fast heart rate become dangerous?
I'm sorry if I keep harping on about this issue, as I have touched on it indirectly in previous posts, but I have read alot of conflicting information both on this site and others that leaves me confused. Basically, I'm wondering if anyone knows when, exactly, a rapid heart rate becomes dangerous. I'm not even talking about SVT or atrial fibrillation or anything, just a rapid heartbeat in a healthy heart, caused by anxiety or caffeine or similar. Is there a point, either after a certain period of time or at a certain heart rate, where one should stop and recognise that the heart is beating dangerously fast and needs to slow down? On the one hand, I have heard that heart rates over about 150 are life-threatening, but on the other hand, I have read that a healthy heart can beat at over 200 beats per minute for weeks on end with no problem. I don't know which to believe, and I want to be able to do the right thing for my body when my heart rate does get high ... and it does!
To understand how this works, remember this:
When you have high blood pressure, the heart answers by thickening its walls, just like any other muscle (so-called hypertrophy).
When you have high heart rate (chronic) the heart answers by dilating the chambers (because it must pump so much blood and trying to adjust by increasing chamber side, which is not a good solution at all).
Weight lifting is increasing the blood pressure without increasing the heart rate and stroke volume so much. For that reason, weightlifters get a hypertrophic heart. People with chronic rapid heart rate can get a dilated heart. People doing aerobic exercise like runners, will get an athletes heart, which is both slightly dilated and hypertrophied (it grows both ways). This is healthy (within reasonable limits). The other two are not.
To your question:
I don't think sinus tachycardia can ever cause this condition, at least not if it's caused by stress and anxiety. Remember, your heart rate is lower than you think because you often tend to measure it during anxious times. When I got my first Holter test, I had the exact same symptoms as you and I was surprised to find out that my average heart rate through 24 hours was actually in the low 70s. Measuring your heart rate will also make it increase.
As itdood said, when a rapid heart rate becomes an organic problem to the heart depends on lots of factors. I assume you meant a chronic condition, not what heart rate is dangerous during acute events like SVT (where the answer is quite simple; if you faint or is close to fainting or get severe chest pain or SOB, it's dangerous (not counting the times when you stand up too quickly, that's normal, I mean during an arrhythmia).
Almost the only time this question is "relevant" is with chronic atrial fibrillation with rapid ventricular response, where the heart is forced to beat at rates >120 for months. Remember that all hearts are different, just like engines. If you drive your MC it's normal to run at 6-9.000 RPM (it doesn't hurt the engine) but an old diesel truck will run at 1200-1500 RPM. Some of us have small hearts with high max heart rate and high resting heart rate, some of us are opposite. Young people tolerate a rapid heart rate far better than older. If the coronary arteries are blocked, the tolerance is also far lower.
The only REAL threat to a high heart rate is if there is structure problems with the heart to begin with. If the heart is hypertrophied a rate of 150 could be dangerous simply because the thickened heart walls cannot relax and allow that much blood to flow into and out of the chamber. People are walking around with A-Fib with rates over the 200 mark all the time and are not bothered by it. Many patients don't even know they have A-Fib. As long as there is no structural damage such as in the case of the cardiomyopathies or congenital heart problems resulting in structural issues, the heart can handle higher than normal rates.
I should reword that, Docs don't "often" treat for sinus tach. What I meant was docs *may* treat a rhythm that is sinus tach if there are other circumstances that require it. The other circumstance list is long. Things like your age, how much tach load per day, risk for clinical issues because of the tach. There's a lot to it.
Thanks for the clarification itdood: that brings my concern down a few notches. It is, however, alarming how these heart rhythm issues are so different for everyone, and treated as such: it makes it that much more difficult to judge the severity of my own problems!
Sinus tach is as far as I know usually treated for symptoms relief, just like PACs and most cases of PVCs.
Sinus tach is benign 99,99% of the time (we ALL have it during the day) but if it has a cause, the cause should be treated (causes are conditions like thyroid issues, anxiety, infections, etc.. this list is long).
I wonder why you don't ask your doctor for a minimal dose of beta blockers if this keeps ruining your life quality? Nonselective ones are possibly best because they also reduces the anxiety.
I don't know what the severity of your problems are. It seems that talking to someone may be the right choice for you. Beta blockers are not for everyone; the side affects of drugs can often times be worse than the problems they are being used to cure. I was on beta blockers for years for SVT, I gained a ton of weight, if that wasn't bad enough I started to hallucinate on them and nearly got my husband and I killed one night while we were driving somewhere. There are a lot of people waklking around that have A-Fib and don't take medicine at all; the main rule of thumb is if there is no structural issues with the heart, than faster than normal heart rates are nothing to be concerned about. While this is certainly an individual thing; that is the general rulew of thumb for most cardiologists. If you have an arrhythmia problem, anxiety will make that problem MUCH worse for you because anxiety causes the body to release adrenaline into the bloodstream and that causes the heart to beat faster to prepare the body to "fight or flight". If you are dealing with these fears, then get help for those issues first; you will probably feel so much better.
I suffer from permanent atrial fibrillation (have been in that state since late 2007). Prior to that time my AFib was controlled by electrocardioversions and Propafenone (anti arrhythmic not a simple beta blocker) and my resting HR was in the lower 60s... I also ran/jogged several times a week.
Now my resting HR runs in the mid-80s, sometimes a bit lower. I think my sleeping (who knows?) HR may be closer to 70, it seem slow on those rare occasions when I wake-up and can hear/feel my heart beat. That said, and again I suffer from AFib, my Cardiologist wanted to get me below 100 at rest, I was running about 130 with low dose beta blocker. I now take 50 mg of Metoprolol, and I think it has some side effects, but it does lower my HR and blood pressure, which was never a problem.
If it sounds like I am trying to answer your specific question, I am not, but chip in the experience that suggests a resting HR of 150 or more is too high. With a 150 starting point, what does your HR go to when you walk, walk fast, or up hill?
Actually, Jerry_NJ, I meant that my heart rate reached 150 on one occasion last week for about 45 minutes. My resting heart rate is usually normal, between 60 and 80, and goes to a number like 150 when I am doing vigorous exercise. It is only on some occasions that it will reach that rate without clear cause. If my heart rate was always that high, I would be in the ER right now!!
As for beta blockers to slow the heart on these occasions, I have certainly considered them, don't get me wrong, but like grendslori, I fear that the side effects may be worse than the symptoms they prevent. I struggle with my weight, and am terrified of gaining. I have also heard of hallucinations and other such effects, and don't want to do that to myself. In short, I fear that they may be more trouble than they're worth.
I agree also that anxiety is probably the principle cause of my tachycardia, and in any case is certainly making it worse. I've been seeing a therapist to start to deal with it, as well as working through it on my own using a self-help book that was recommended to me by another therapist, so I guess I will have to see how things go. So hard not to worry!
Okay, a HR of 150 when exercising isn't too high, if in good condition a 23 year old may be able to sustain a HR approaching 200 without it being a problem. Please, I am not suggesting you exercise at a HR of 200.
When I was still running in my early 60s (years old), I would have no problem holding 150 for 30 minutes or more. I considered 150 to my my safe steady-state limit. I might hit 160 or more, but would slow down when that happened.
Good luck with the efforts to control/settle emotional stress. Try to believe in yourself as a starting point,
My hr's are whacky - I can be at 50 the lowest my PM will let it go and jump to 200 - 220 in an instant doing nothing and it stays sometimes for hours; it hurts, make me sick to my stomach but will eventually go back down...what's helped me is Inderal extended release and I have no side effects on it and haven't in the almost 2 years I've taken it.
Hr is a very quirky thing like bp; dr's can't believe I have 350-425 in the V rates that my ICD picks up on and I don't have any problems from it. Sometimes I wonder how much more my heart can handle until it just gives up from being so worn out.
What I find strange is when i'm stressed, anxious or get mad it doesn't necessarily go out of rhythm or spike right then; it's usually when I finally calm down that the problem starts.
Have you thought about therapy or trying a bb just to see if it will work? Inderal is supposed to help not only with arrhythmia's but it's an anti anxiety med or anxiety performance (mushy brain today so I can't remember) and my cards dr said there were 5 or 6 that do can with both.
I'm 16 years old and my heart rate feels different and I have acid reflux but sometimes I feel like someone's sitting on top of my chest and I'm gonna stop breathing then it freaks me out so I get these pains and my heart rate increases cause I'm scared and my parents think its just the acid reflux but it feels weirdly different to me . I am over weight I'm about ranging from 250 to 265 . I lose weight for a Lil while and was at 216 . But then went off my diet and gained a lot of weight and I don't know how to control it and sometimes I feel like I'm just floating in my own body like I'm not even there and no one understand where I'm coming from . Everyone thinks I'm lieing but I'm not and its scaring me .what could it be?
krissy, I have very acidic blood and acid can cause all kinds of issues. I suffer with severe dizziness and that out-of-the body sensation that you are describing. The only thing that I find that helps is taking Milk of Magnesia for 4 or 5 days at a time when the acid is at its worst. Just take the antacid dose - 1 tablespoon a day with food. Don't take this every day, just take a course of it as needed when your symptoms are bad.
Also, read up on all the healthy foods out there that we need in our diet every day. Focusing on eating healthy should help to bring your weight down. And stay clear of any foods that are acidic. If you are suffering with digestive problems this could be causing your feelings of distress around your heart. Also, check the internet for natural ways to help weight, acid and indigestion.
This site complies with the HONcode standard for trustworthy health information.
The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. Med Help International, Inc. is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.