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Richard N. Fogoros, M.D.

Inappropriate Sinus Tachycardia (IST)

By May 31, 2013

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Inappropriate sinus tachycardia (IST) is a condition in which an individual's resting heart rate is abnormally high (greater than 100 beats per minute), their heart rate increases rapidly with minimal exertion, and their rapid heart rate is accompanied by symptoms of palpitations, fatigue, and exercise intolerance. It is more common in women, and (while one hopes not) this may be why it is all too often written off by doctors as "anxiety." Read about IST, its causes and treatment, here.

January 28, 2009 at 9:35 pm
(1) rebecca says:

i think that it is utterly wrong for doctors to pass of a condition like this as something as low as anxiety just because we are women. what a sad world this is..

April 11, 2009 at 7:32 pm
(2) winwin says:

I have IST and I have had it for several years. I am 22 now and I was diagnosed at 17. I firsted experienced symptoms at 16 and I was also told I needed pycho therapy. The doctor basically told me nothing was wrong with me and I was nuts! For a year I suffered with pains and many other symptoms and my doctor continued to tell me I needed counceling. It even got as bad as my license was taken away from me because my doctor sent dmv a letter stating I wasn’t in the right state of mind to drive. This was devastating to me just 16 as I was excited to drive. Finally after a year I found a specialist and was admitted into the hospital for a week of test. I was dignosed and tried a few different meds. I finally found the one for me and now I am able to live with this condition. Some doctors are simply heartless!

May 15, 2009 at 4:35 pm
(3) Renee says:

I was diagnosed with IST in my 20′s. After 5 sinus nodes ablations, my rhythm stabilized and I was “normal” for a period of two years. While skiing I went into a junctional rhythm. I required placement of a pacemaker. My first pacer was placed in 2000. I have had one revision and am better than ever. I walk/run marathons and continue to ski and do anything I want. I do not require any medication to control my rhythm. My heart continuest to have normal beats from the sinus node, the pacer functions when the sinus node fails. I am pacing 82% of the time.

September 7, 2009 at 3:44 pm
(4) Debbi says:

I have had problems since 1982 when my first child was born. Nothing was ever done, but it didn’t really bother me either. Years later is has made my life miserable. I am now 49. I have had to quit work, I have a mobility cart for places that don’t supply them. I can’t take most the meds because they really upset my asthma. My doctors won’t do ablations or a pacer yet. They tell me even if they do it will not help the symptoms at this point. I also have many other things wrong. This disease really stinks. I am trying to get disability, but the government seems to think I can do something. Maybe on a rare good day, but mostly I am really fatigued. Good luck to all.

November 12, 2009 at 10:46 am
(5) Treading says:

I was diagnosed with IST shortly after open heart surgery for Mitral Valve repair about 5 years ago. I have tried more meds than I can count. The doctor feels most of my issues are caused from my stressful job and the adrenaline rushes it provides.
We are still trying to find a balance of meds that will sustain me through the stressful periods of work at least long enough to make it to an early retirement which I hope will be in a few years. In the mean time I feel like I am using all my energy to keep my job and losing control of everything else. I am exhausted by the time I come home so everything is suffering from house cleaning to bill paying to even spending time with friends. All I want is to sleep. Sometimes I feel as though I will have a meltdown before I can every get free of the stressful job to see just how I would feel from that point. By the way, I am in my 40′s so feel like this illness has robbed me of some prime years. I am fortunate to have a good doctor but it isnt helping a whole lot except does give me the reassurance that it is not all in my head…that it is a real illness, more destructive internally than anyone on the outside would know…and that better days will come when I am free of the high stress job. Unfortunately, I have to stick this out as I very much need the health insurance benefits. Anyway, that is my story……

November 29, 2009 at 1:45 pm
(6) CROUCH says:

i have this as well and it took many many tests to confirm. i take metoprolol tartrate for it…

December 15, 2009 at 8:51 am
(7) Kristen says:

I was just diagnosed with this about 6 months ago. Before that I had NCS (Neurocardiogenic Syncope) I was diagnosed with that when I was 17. After a year of testing and was given my last test which was a Tilt Table Test it was then after the results I was told I had NCS. I’m now 23. I also have along with IST, PAC (premature atrial beats or contractions) thats when my heart skips beats and it flutters making it feel like it’s going really slow. I’ve been on several different beta blockers but the one that has worked for me for about 2 years is Atenolol and I’m on 100mg. It’s a very frustrating heart condition to live with, especially with mine because my heart palps happen at night when I go to sleep, it’s very hard to try and sleep when your heart feels like it’s going to jump out of your chest, or the opposite where mine can go extreamly slow. My lowest BPM reading I took before was 28bpm. That doesn’t happen all the time. It’s more of a rapid heart racing for me.

January 26, 2010 at 2:11 am
(8) cindy says:

These all sound too familiar, it all started with my second pregnancy in 1985. I was 25, who knew i would chase cardiologists, and drs for 25 more years. I always told them i was weird, my heart raced for so long at 150bpm. Then i had SVT’s was ablated for that. Saved my life. I feel for anyone who has this, family and friends just don’t get it. How they would live this way, i don’t know. Good days, then for no reason bad. I laugh when people tell me they have palpatations that have lasted for a couple of days. Good luck, those of you with IST.

March 19, 2010 at 10:50 pm
(9) Jamie Warren says:

Can this be fatal if the heart beat gets to high?

March 21, 2010 at 9:34 am
(10) heartdisease says:

No, but a very high sustained heart rate (probably 130 bpm or more for several months) can produce heart failure.

April 12, 2010 at 2:34 pm
(11) M says:

FYI – I’m a male and have been suffering from IST since I was 29 years old. I am now 38. It has gotten worse and better, and worse and better again over the years. I am under the care of the Mayo Clinic and at their suggestion I now take 5mg of Midodrine 3x a day which helps with the symptoms, particularly the dizziness and lightheadedness. I previously took atenolol, which helped for a period of time.

This is NOT a cardiac condition – the cardiac issues are just an obvious symptom. I cannot recommend enough going to a place like Mayo to get a real diagnosis and treatment options for your condition.

May 26, 2010 at 1:31 pm
(12) Holly says:

I have had every single symptom for 2 years now, but I played it off as being related to being out of shape. I went to the doctor when I thought I was having a heart attack. He was quit concerned and said I needed a stess echo. I said no that is a waste of time, do an ecg and I will be fine. I wore a halter monitor for 30 days and it said sinus tachy. So again I figured it was bc I was out of shape. I went to the doctor to get a refill of an AD/HD drug that I was perscribed 3 years prior and he said no not untill u get the stress echo.
So I went yesterday. I stood up to get my BP and it was 100/58, I was sweating, spinning and felt like I was going to pass out. Which I figured was normal, for me. Sitting BP 124/80. Hummm… not normal, that big of a difference in 30 seconds. Sitting HR 78. (normal 60-100) I am getting ready to start the test and the HR goes to 120. (just by standing) 30 seconds into the test it jumps to 187 and I am about to pass out. The cardiologist jumps up and starts tapping the screen and messing with the wires and asking if this is right. I said YES!!! This is what I have been saying and everyone thinks it’s in my head. He said no u have IST. I had no idea what he is talking about but was sooo happy someone believed me. He said I need an ablasion and a pacemaker. Now I am only 30 so I do not want that. I am going to OSU, so the best u can get, and I want to trust their decision, but I do not want a pacemaker. Any doctors out there that can give me any other alternative, that would be great! I have read u can wait it out and u can take a beta blocker, but betas are not proving to be that great. I want to go into my appt armed with as much knowledge and facts as I can, to not only be informed but to also be an active participant in my care. By the way, thanks everyone for your posts they made me feel normal, gave much info, and helped me to relate. Thanks doc for doing the research and publishing it for us, it truly helps.

June 9, 2010 at 2:19 pm
(13) sasha says:

I was diagnosed with IST 2 weeks ago, even though i’ve suffered with it for 6 years now. It really is horrible when you have 2 little boys to keep up with and your heart won’t let you. I couldn’t go outside with my boys without the heat affecting me or even just the walking. I could even just sit there and do nothing and my heart rate would spike up to 170 bpm. It would take a few minutes to a few hours to go away. But now i’m on corgard 10 mg twice a day. This really works for me and i’m so exited to see a change. My doctor says it goes away with time, but sorry. I don’t buy that. My grandmother has had this condition since her teen years and it’s only gotten worse. And then looking at all of you, i’m just accepting this heart condition in my life and managing it to the best of my ability. Thank you all for the supportive stories. It’s great to know i’m not alone.

June 14, 2010 at 11:00 pm
(14) Yusuf says:

To M
As a doctor I cannot see how Midodrine can help you for IST. It is used for symptomatic hypotension – for symptoms like dizziness, and especially after getting out of bed and standing, lightheadness, feeling faint through low blood pressure.

Midodrine is a constrictor of blood vessels and used to increase systolic blood pressure in persons who have symptoms as descriobed above through extreme low blood pressure (hypotension).

August 19, 2010 at 10:46 pm
(15) lisa says:

a year ago i started to get very dizzy, lightheadedness, sob, sweating, and very weak when i just clean my house. it was very scary and i went to my dr. and ran several blood test and could not find anything. After 3months it went a way. So i let it go then 8 months later it came back and back strong. Now i have palpitations, fluttering of the heart, irreg. hear beat along with the other symptoms. If i sit down i’am fine with 4half year old twins that is very hard. Stairs get me to the point i pass out and went to the Er. My ekg was normal and my family dr. is on myside. She did a stress echo and when i got on the tredmill i got very dizzy, sweating, and very sob. I got close to passing out again. I thought this would finely answer something, but my echo came back normal. My dr. started me on beta blockers to see if it helps. I’am glad my dr. is willing to help. It completely has change my life and i”am 0nly 31. I still don’t have a dx. After reading about ist I wonder if thats what i have?

August 25, 2010 at 3:57 pm
(16) Chelsea says:

You guys really need to relax. I also have IST and have been fighting with it. I don’t respond to medications. My normal heart rate is 130 and can often times go over 200. I have also been to Mayo and went under all sorts of test. Who ever it was that said this wasn’t a heart issue your an idiot. My understanding from all the specialists I have seen is that this isn’t life threatening. Yes it sucks to deal with and affects your quality of life but it could be a lot worse.

August 29, 2010 at 1:20 pm
(17) Jackie says:

Thanks, Chelsea, I needed everything you just said.

December 21, 2010 at 1:53 pm
(18) Tiffany says:

I am so thankful that I found this article…I have been having problems just like this for over a year now and have been put on antidepressants, sent to a therapist and told that I have anxiety. The problem is that I DO NOT SUFFER FROM ANXIETY. I feel horrible that my condition is being treated the way that it is. Suffering from anxiety is a serious condition and should not be taken lightly, but just because they cannot prove that I have a condition should force me to be labeled with a different condition that they cannot prove. I plan on taking this article to my new cardiologists to see what light he or she may have on the situation.

January 1, 2011 at 6:25 pm
(19) Debbie says:

I’ve had issues since I was young. Never realized it was abnormal, it just was. When your in your pre-teens, you have no idea. By the time I was in my twenty’s I’ve had enough physicals that if there was a problem with having a resting heart rate of over 130, I figured the Drs would say something. They didn’t. When the syncope episodes really started kicking in by my 30′s, I figured something had to be done. I heard all of it. I’m anxious, I’m a woman, white coat syndrome etc. I even was told my heart rate of 150+ was NORMAL! After MANY doctors (and many laughing doctors) I finally found one that listened and tested. So now in my 40′s I find out all the problems I have. Not only is IST one of them, but I was diagnosed with a murmur, HCM, AFIB, AFlutter, among others. I think what really made me happy was the validation that there was a problem. Finding an EP Cardiologist that LISTENED was a God send! What’s funny is just 2 months earlier, a different Cardiologist gave me a clean bill of health! After multiple ablations and many different meds, I’m working on control. It didn’t happen overnight, can’t get fixed overnight. Why worry over that you can’t control. I’ve lived with these symptoms my whole life. Have been very active and will continue to do so. I just really understand life is short, enjoy it. I believe, like most of you probably do, its not really the issues, it’s the fact your not taken seriously. I actually find it comforting at times to hear my heart racing, and feeling it while I sleep. I know its beating! Main point is you know somethings wrong. Don’t stop trying to find someone to help. Someone will listen, you just have to be tenacious.

January 17, 2011 at 8:01 pm
(20) anne says:

i have 2 artificial valves on 2nd pacemaker have very bad episodes of tachycardia i am on meds verapmil for slowing heart rate my legs swell up some times i get pain in l arm and chest but when i rest it finally stops have this problem 2 yrs now i am 60 have a heart problem since 25 yrs old dr said i now need both valves replaced again soon afraid of ablation with already haveing 2 valves replaced and 2nd pacemaker

January 21, 2011 at 4:08 pm
(21) Nichole says:

I was diagnosed about 2 years ago- usual symptoms, fast heartbeat, minimal exertion skyrockets the bpm, dizziness, shortness of breath… My original GP told me quite a few things were wrong with me before I ended up in the emergency room. He told me I was depressed and pushed samples in my hands when i protested I wasn’t depressed in any way shape or form(i was crying i was so upset that he was insisting that i had an anxiety disorder-which im sure didn’t help my case). When the symptoms did not stop, he prescribed me an inhaler(presumably because of my shortness of breath when walking around) dr. then told me he couldn’t do anything for me and gave me a referral to a lung specialist. (?!) Needless to say, I ended up in the ER (12 hours in ER) and they were stymied. (didn’t hurt they were monitoring the wrong screen-they were checking someone else’s heart instead of mine) Finally ended up being admitted after the dr. used his fingers to monitor my heart rate when i insisted it was high and they said the monitor wasn’t showing it. Stayed 3 days and finally ended up throwing a fit to leave when nobody gave me answers or visited (one cardio visit in 3 days) . Cardiologist I saw after the hospital said my GP was a fraud/incompetent and he couldn’t understand why they diagnosed/prescribed me the wrong meds in the hospital.(one of his respected colleagues no less) Dr. said that because of my age(29) that most people were inclined to attribute any heart problems with “anxiety” instead of probing for the real problem.(i was one of his youngest adult patients ever) Now on 1 beta (atenolol) plus digoxin and my symptoms are incredibly better.(except for occasional bradycardia) Point of the story being that women are definitely treated differently in these type situations(i guess popular opinion thinks we are more likely to invent/hallucinate things ?! ) and that being in charge of your own wellness instead of listening to all diagnoses is really important!

January 22, 2011 at 9:19 am
(22) Izarlia says:

I started experiencing symptoms a year ago and kept passing out, I had several ECG’s, blood tests, a 24 hour holter monitor, an Echo, and a stress test which after about 20 seconds showed my heart rate to be 225bpm at just a walk. They said that my heart rate was very slow to come down and refused to go below 140 after for sitting for 10 minutes completely still. However even after all these tests they just said to get on and live with it! So I did, for about 6 months which is when it started to get worse, I am in the middle of exams at the moment and I get so so tired, and keep passing out for no reason. I’m finding it so hard to revise for my exams because I am just so tired all the time. I went back to the doctors about a month ago and straight away he said that he was surprised that the cardiologists hadn’t done a 7 day recording- so finally I’m getting one! I hope to god that they do something about it, because although I don’t particularly want to go on medication I just want it to stop interferring with my life! The doctor said that I almost definitely either had SVT or IST and that we needed to find out quickly. I am so glad that something is finally being done! I feel so bad for the people who get beaten down and are being told it is down to anxiety, if they don’t have it themselves, then how can they say what it is that you are experiencing without doing the proper tests? I agree with Nichole- it’s unfair for them to make presumptions because women supposedly “overeact more” and are more prone to anxiety, it’s ridiculous!

February 1, 2011 at 1:30 pm
(23) Christine says:

Hi All,

I am 25 and I’ve had IST for about 10 years, of course when I was a teenager everyone just thought that I was lazy/out of shape – ignoring the fact that a was a dancer from age 5-12 and from 12 on participated in a sport a season. I am still in relatively good shape, but I am hoping that someone has some suggestions on a workout plan. I am on 50 mg Toprol XL/day which helps keep my HR under 200 bpm, but my doc says to keep in below 180 and he wants me to run…that is impossible. Has anyone found a certain type of exercise to work at keeping your HR lower below the level of symptoms (ie, lightheadedness, nausea, syncope) that still allows you to build stamina?

February 12, 2011 at 3:52 pm
(24) K says:

I was diagnosed with PSVT at the age of 18 and whilst still in hospital found to also have IST. Since then I have tried and tested many different beta (atenolol and metoprolol)and calcium channel blockers (diltiazem etc.). I have now been prescribed Ivabradine (5mg twice daily) – it’s an angina medication and is brand new (within the last 5 years – nothing else like it), and not technically licensed for IST. But the whole thing about this medicaltion is that it works on slowing the sinus node, reducing the risk of going into ‘an attack’, and has made the greatest impact on my life (i got to the stage of being almost house bound). Hope this helps those who are just getting a diagnosis, or current medication is not working – the only thing is – its expensive – but what price on quality of life?

March 7, 2011 at 7:20 pm
(25) Ashley says:

Hi everyone,
I didn’t realize so many people were suffering with the same illness. I am 17 years old and was diagnosed with inappropriate sinus tachycardia last year. I have been on some medicines that have been mentioned in previous comments, however i don’t feel that they help. One made me extremely fatigued and another doesn’t even touch my symptoms. This is frustrating. My doctor said i am way to young to consider surgery, which i was very pleased to hear. I have had a holter monitor, cardio-net monitor and am currently being monitored by a zio patch. My doctor has scheduled a stress test for this week and then he mentioned giving me a stronger medicine. So until he and i can figure out what will work to give me a better quality life it seems to be a guessing game. I am sorry for all of you who are suffering with this same illness.Stay positive everyone. I just thank god that it is treatable and not life threatening. I think one of the worst parts is not being able to be active, play sports and run. Not to mention the dizziness and shortness of breath. But hey, it could always be worse right?

June 11, 2011 at 7:47 pm
(26) William Gordon says:

Hi All,
I’ve had most of the symptoms others have mentioned which indicate IST but the difference seems to be that noone has mentioned the ‘innapropriate’ bit – which I take to mean that there’s no ‘pattern’ in the timing of these attacks. I can go up to 3 months perfectly ‘normal’, then without any warning it suddenly starts thundering away >100 beats per minute (can’t be accurate, ‘cos I can’t count that quick!)They usually last for about an hour if I just sit quietly and watch TV,read etc. – but I feel absolutely ‘wacked out’ afterwards. I also have hypertension and take Lisinopril (half a 5mg tablet twice daily)for that,plus one 20mg tablet of Verapamil daily.(I went on the new drug approved recently here -Dronederone, but had to come off it after a month because my blood tests were showing my kidneys were being affected by it,so now back on the Verapamil)If I get a bad attack and my pulse hasn’t stopped thundering after about an hour then I take a 10mg tablet of Bisopril (cutting out the Verapamil)which apart from one occasion seems to do the trick.
My cardiac consultant wanted me to have a catheter ablation, but as the attacks are so infrequent balanced against the risk of the intervention I’ve decided to naintain the status quo unless there is a change in this irregular pattern.

December 6, 2011 at 1:28 pm
(27) Tracy says:

I have been diagnosed with IST and it is no fun road but i also have other health conditions that have really toppled me over the hill in a little more than 6 months i have hypoglycemia, pcos, sinus tachycardia, and a antiphospolipid antibody syndrome with hypercoauable state and miagraines all this is bout toput me under and not aboe to work

January 2, 2012 at 1:44 pm
(28) L says:

I was diagnosed with IST 5 years ago, where my resting HR was about 130. Any sort of activity would bring about HR of 180 or more. Luckily I saw a cardiologist who believed in my symptoms, performed all necessary testing, and had medication suggestions right away. I have since been taking Bisoprolol for the condition and have found it to really help the issue. I haven’t seen many others using this medicine in this forum – but it may be worth a try to some, as it really did change things for me and let me live without worry again. I have been able to resume all normal activities as well as a vigorous excercise routine – and so far have only become more confident in my ability to continue on with this condition. Although medication is never my first choice – in this case it was really a saviour for me. Good luck to all…

May 17, 2012 at 6:05 pm
(29) Jenn says:

I have had every diagnostic test under the sun. I had an issue simialr to this following a respiratory bug in my mid twenties. It went away though. Then now at 39 I have had another respiratory illness and my hr is tachying away. Looks like possibly a pfo and atrial anneurysm in addition. Waiting on a bubble study. Didn’t tolerate Lopressor…now starting Atenolol. If I take the stairs…I’m done for the day. I’m way to young for this.

June 1, 2012 at 7:55 pm
(30) Dawn says:

I am pretty certain yhat i have had symptoms of IST for a few yrs but wasnt diagnosed till 4/12 and was put on lopressor with gradual increase to now taking 75mg 2x day which helps keep my hr less than 130 most of the time but it has been horrible with my asthma. I am now taking nebs 4-6 x day, symbicort, combivent, singulair and all i used before was an occaisional puff of proventil. My EP doesnt think its important enough to change my meds, but when i return in june i am demanding a change, i am spending a fortune in meds to counteract 1 med. He also prescribed florinef for the syncope, and now Im swelling up like crazy and gained 10 lbs in a wk but no one cares! I know florinef is a salt saving med to increase blood volume and i havent passed out since starting it but the side effects worry me. When i started with severe enough symptoms to go see my GP he said ANXIETY take this pill, then i come back to him in a wk saying its not helping at all- i was having SOB, resting HR> 110 and as soon as i would stand it would go >160, my BP fluctuates so much- sometimes 80/55, or 140/90, i have extreme fatigue, palpitations including PAC’s, PVC’s, PJC’s, ventricular bigeminy, atrial bigeminey, PSVT, and sinus arrythmia’s. I also have alot of CP. I have since developed intentional tremors (unilateral), speech delay/studder- and all my docs want me to see a neurologist and the think i may have MS. I have been off work since FEB 14 when I went to the hospital for 4days and found out NOTHING! Other than changing the anxiety med and adding antidepressant. Which i am still taking and i have minimal improvement, thanks to all of you, I know there are more med options, THANKS!!!!

June 15, 2012 at 1:27 am
(31) Esmae says:

I also have innapproiate sinus tachycardia. was taken to the emergency dept 12.30 in the morning. After blood and urine tests wired up to everyhting possible e.c.g. was diagnosed with I.S.T. My pulse was up to 140. b.p.m. After injecting me with a serum and nothing happened, I was just hooked up to moniters and evaluated in the cardic unit.
I am now on Antenolol 25mg. twice a day which is working wonders. I have no tea coffee soft drinks or anthing that have a bit of stimulant in it. Cut back on sugar intake. Very Scary I know what people are going through with it. Glad to know there are people out there to talk about it.
It helps so much.

July 1, 2012 at 12:42 pm
(32) Lisa says:

Hi Esmae, I was so glad to read your note, I have also been diagnosed with IST (or at least that’s what they think it is) with my heart rate going up to about 170 bpm, particularly at night time, very scary indeed. I have had two ablations but the problem has only got worse so as a last resort I decided to take 25mg of antenolol daily and touch wood my heart rate is always at a nice steady rate with no attacks for 2 weeks. I just hope this continues. It’s reassuring to know it has also worked for you :-)

July 6, 2012 at 5:46 pm
(33) Cheyenne says:

I was diagnosed with IST last September when I was 15. It happened out of the blue one night and I started coughing really bad. The next day it felt like I was having a heart attack, it was so painful that I cried. This horrible pain lasted 3 days and then it started to hurt a little bit less. My mom thought I was just being a kid and wouldn’t take me to the doctor, finally after a month of terrible pains she took me to the hospital clinic. I scared the nurse because she went to listen to my heart and it was a resting heart rate of 160.
I really hate having this condition because I’m almost always in pain and usually get fatigued very easily. It makes it hard for me to sleep at night because my heart feels like it’s going a mile a minute and the pains it causes will wake me up. The doctor told me that he didn’t want to give me the beta blockers because he felt I was too young and would leave the decision up to my mom.
I’ve begged my mom for them but she thinks the same thing. I would love to get rid of the symptoms or at least reduce them but I’m only 16 and no one will hear me out and because they don’t have the condition they’ll never understand. It sucks having IST and hopefully I’ll be able to get treatment for it soon.

July 6, 2012 at 8:12 pm
(34) lou says:

Hi all, so sorry to hear so many of you have been mis-diagnosed/still suffering. It is such an awful feeling having your heart racing like your running a marathon and regardless of the reassurance that it is not fatal etc it is still hugely alarming and can really take its toll on life. I woke up in the middle of the night in Feb 2007 with a racing heart, ignored it for a few days until I finally dragged myself to A&E (by this point I could barely stand as it gave my synscope) I then spent 1 month laid flat on my back in a local hospital (everytime I even raised my chest to sit up my heart rate would jump up to 200+. They had no idea what to do with my adenosine,calcuim blockers,verapamil etc, nothing worked. Finally sent to London hospital (St Mary’s) and began the long long process of several ablation’s. I was in hospital for 5 weeks and then sent home still very unwell and very scared that It would stay that way. However they never gave up on my and it took 5 ablations (the last one being PVA ablation and I have never looked back!!! I am lucky that I don’t take any medication now and although I will possibly never be as well as I was prior to this happening my quality of life is much much better. The only thing that will ever set it off now is either drinking alcohol (even a sip sometimes!?) or If I am really really tired. So please don’t give up guys it took me nearly 4 years to get through all the ablations/in and out of a&e etc. I wish you all lots and lots of luck.

July 26, 2012 at 9:52 am
(35) Karlene says:

I have finally gotten a diagnosis of inappropriate sinus tachycardia (IST). They also believe I have increased vagal tone which makes my heart best extremely low. My heart beat ranges from 30-225 at any given time mostly at EEG. IST is associated with young women who are health care worker- I am an RN, an EMT and an Army Medic- do any of you fit the profile as well? They gave me a short acting beta blocker for when symptoms get bad called interol. Many medications don’t work with this syndrome as the heart rate fluctuates so often. They also gave to zofran to help with the intense nausea. What I foun weird even being a nurse is that they told be I never need to the ER unless my pain is different- even when intact syncope (fainting) sometimes I’m unconscious for long periods of time (5-15minutes) until my heart can fix itself. Sometimes free exercising my heart ate stays eleveated hours. What they said is best though is to exercise so that our resting eart rates are lower, eat small frequent meals and to listen tonite bodies. At this rate we all know we are not making this up. Best of luck! Living with this has proved difficult. Most days i want to sleep while others I am running around like a maniac! Gotta love this crazy thing called life!

July 30, 2012 at 6:57 pm
(36) Justice says:

Diagnosed with IST 16 years ago, after terrible URI. Drugs do not help. I am NOT suffering from anxiety, just anger, from all the money wasted on ignorant Docs! I was Rn, cannot work, and barely function at home. Never tried for disability, but Docs wouldn’t help case, anyway. Took me years to get a diagnosis. They do not care about what they cannot instantly fix with a pill. I am through with western medicine for this problem! Going to take up accupuncture treatments and herbal supplements, since all else has failed me. What do I have to lose? Being a healthcare worker just makes this all the more difficult, as I know how my health is slipping away from me, and I would do anything to fix this! I dedicated my once great career to helping others, and get nothing but dirty looks from so-called experts. When they need a nurse one day, I hope they are treated like a crazy half-wit!

July 31, 2012 at 1:08 am
(37) Dianna Mariscal says:

When I was in high school i was a athlete/runner…when we had our medical exam ecg…the doctor said that i have a sinus tachycardia and he said that i should monitor my heart rate whenever i have to run…the did not sign my medical certificate and it ended that my coach did not allow me to join the competition…It really bad for me because since i was in grade school i always run i don’t know why the doctor didn’y sign my med. certificate…
Is Sinus tachycardia not good for me to run? or join a compitetion?

August 11, 2012 at 6:49 am
(38) Lauren says:

I have had IST since I was 13yrs. My mom just thought I was lazy and needed to exercise. Well when I was in High School they forced me to do PE and run. My hr would go to 250bpm and sometimes I would pass out in class. My PE teacher would just take me to the health room till I woke up then I had to go to class. I had PE every day and it never got any easier to exercise or run. I went to a cardiologist and wore a monitor the year after I didn’t have to take PE, they said I was to young to do anything. Well it got worse and I found a great electrophysiologist he put me on medication. It got so bad I was on 100mg Atenelol and 240mg verapamile. I also gained a lot of weight from inactivity. This hole time my mom just says I’m fat and I need to work out. People don’t understand that it is so draining and just so hard to exercise.I can’t even walk up a stupid flight of stairs without being short of breath. I had an ablation recently, had a bad reaction to the adrenalen but am now only on 25mg of atenolol. My family still thinks I am lazy and that I should get off my fat but and work out but you know what. I went to the doc a couple of month after the ablation. Sat down my pulse was 70bpm stood up it went to 160bpm the nurse freaked, I was fine. I still can’t do much because I have asthma now and have bad joint problems but I just wish my mom and family would get that I just don’t feel good and that I am not just fat and lazy.

August 16, 2012 at 3:02 pm
(39) Kayla_US Air Force says:

I am a 25 year old female, and have been diagnosed with IST for about a year now. What most of you are saying is so true…This really is life changing. At times extremely annoying. I was extremely healthy other than having chronic migraines before I was diagnosed. I went from being an award winning happy hard working military person to someone that now has no life. My resting heart rate never falls below 140 and at times with movement it hits 190ish. I can no longer do my job, drive due to black outs, work out, or have much interest in anything because I am always tired. I have went through every test possible you can think of. EX. EKG’s(alot) all show Sinus Tach or SVT, blood tests, hormone test, pheocromocytoma, carcinoid, stress test, Ultra sounds of heart and carotid art. ct angio grams, 2 sinus node modifications, I have tried toporol xl, midodrine, and digoxin. Now we are at a stand still. As of right now I am on 200mg of Toporol XL, 10 mg of midodrine, 0.25 of digoxin. And nothing I still sit at about 140. My doctor and I have discussed several things such as Removal of the Sinus node with a pacemaker, AV node abllation with a pacemaker, freezing part of the sinus node with a pacemaker, ablating the AV node and removing the Sinus node and put a pacemaker. For those of you that hate that option there is an experimental drug out there. I refuse to take it because my body is well just too picky. Only problem is it is not approved in the US only Canada and UK. Called: Ivabradine—http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1448693/…this may work for you. Hope this helps!

September 3, 2012 at 8:09 pm
(40) Kay says:

I was diagnosed with a form of tachycardia in march this past year. (im not very sure what kind because i was never told after the ecg) im assuming its innappropriate sinus tachycardia. Ive been suffering from it since i was 18 (im 22 now) i was ignoring my symptoms for 4 years. My heart rate would be constantly at around 110bpm sitting down. Standing or walking it would go past 140. My blood pressure was 117/73 at 110bpm. Now since im on 12.5mg atenolol, my blood pressure goes down to 87/59 at times and i get very tired but my heart rate is 70-96bpm depending on heat factors. But in the middle of the night sometimes, i still wake up with my heart racing. Im assuming its because my dose is finished for the day. But im coping much better xD

October 14, 2012 at 7:45 pm
(41) Elsie says:

I was diagnosed with Sinus Tachycardia in Feb 2010 after trying to ignore it for about 6 months. I’m like most of you as far as symptoms…fast heart rate (especially at night, hovering around 160-180bpm), that sensation of my heart skipping a beat (actually it felt more like it was doing a backflip), anxiety while being exhausted at the same time. I was lucky to have a Dr. who listened. After a gamut of tests though & even a new MD (because I moved out of state) who ran her own tests, they still don’t have a cause. My heart is healthy. I was however addicted to caffeine & am overweight. I take 100mg of Metoprolol twice a day (the smaller dosages quit working after about a year) & have been off caffeine over a year now. Exhaustion has become the norm, however, and I haven’t been able to force myself to even walk for 15 minutes, let alone anything else. The high dosage of my meds are much to blame for the constant tireness I’m sure, but I hate the racing pulse much worse. I’m like all of you in that I’d never heard of anyone else with Sinus Tachy. before & I have since discovered tons of people…mostly women. My Dr. monitors my symptoms every 6 months & I’m not too worried about my heart rate, but DO worry about my heart health as both my parents had bad hearts…my Dad passed away of congestive heart failure & my Mom has had 2 heart attacks caused by excessive plaque buildup in her arteriesl. So far, my cholesterol is great & my heart is strong. I really need to get active again but all I want to do is sit and sleep. I’ll be 40 in a couple months & feel cheated out of what should’ve been some great years. I’m stubborn, but can’t seem to find the stamina I need to get out there & move. That’s I’m trying to work towards…more activity. I don’t know if it will help the Sinus Tachycardia but if my heart stays healthy then I’m all for that.

October 14, 2012 at 7:46 pm
(42) Elsie says:

I was diagnosed with Sinus Tachycardia in Feb 2010 after trying to ignore it for about 6 months. I’m like most of you as far as symptoms…fast heart rate (especially at night, hovering around 160-180bpm), that sensation of my heart skipping a beat (actually it felt more like it was doing a backflip), anxiety while being exhausted at the same time. I was lucky to have a Dr. who listened. After a gamut of tests though & even a new MD (because I moved out of state) who ran her own tests, they still don’t have a cause. My heart is healthy. I was however addicted to caffeine & am overweight. I take 100mg of Metoprolol twice a day (the smaller dosages quit working after about a year) & have been off caffeine over a year now. Exhaustion has become the norm, however, and I haven’t been able to force myself to even walk for 15 minutes, let alone anything else. The high dosage of my meds are much to blame for the constant tireness I’m sure, but I hate the racing pulse much worse. I’m like all of you in that I’d never heard of anyone else with Sinus Tachy. before & I have since discovered tons of people…mostly women. My Dr. monitors my symptoms every 6 months & I’m not too worried about my heart rate, but DO worry about my heart health as both my parents had bad hearts…my Dad passed away of congestive heart failure & my Mom has had 2 heart attacks caused by excessive plaque buildup in her arteries. So far, my cholesterol is great & my heart is strong. I really need to get active again but all I want to do is sit and sleep. I’ll be 40 in a couple months & feel cheated out of what should’ve been some great years. I’m stubborn, but can’t seem to find the stamina I need to get out there & move. That’s I’m trying to work towards…more activity. I don’t know if it will help the Sinus Tachycardia but if my heart stays healthy then I’m all for that.

November 30, 2012 at 9:36 pm
(43) Kmac says:

I have sinus tachy but also when my heart rises I get a sensation in my arms and head that excelerates and I literally feel like im going to.die. Ot most.always happens in the middle of the night when im sound asleep. Not every nigjt but more often than not. Take metropol

January 7, 2013 at 2:30 pm
(44) Lindsey 38 says:

I am 38 and was recently diagnosed as having anappropriate sinus tachycardia. 3 years ago i had to have my gall bladder removed as i had gall stones. However, the hospital wouldnt discharge me as i was tachycardic. They done every blood test imaginable inc a blood gas test, but never found anything (although this was only general consultants, i didnt actually see a cardiologist.) They discharged me after a week and said it would probably settle down post operatively. However, 3 years on and it still hasn’t and has continued to rise and my symptoms have become more aggravated. I have now finally been to see a cardiologist who has diagnosed my condition however, i have had to have 24 hr ecg;s and echocariograms to confirm and am waiting for the results. I have been put on ivabradine tablets to reduce my pulse rate, which seems to br working. However, my main question is whether it can be linked to migraines as my migraines were geting worse as my pulse rate was increasing even though i was on preventative medication. However, since being on the IST medication my migraine attacks do seem to have reduced. When i asked my cardiologist if he thought they could be linked he said he thought it was unlikely however not much is known about the condition IST itself.

January 18, 2013 at 6:17 pm
(45) Krystle 23 says:

My heart rate goes up to 140-160 just taking a shower. At work (LPN in Nursing Home) it has gone up as high as 192. I was monitored for 24 hours and found that when I sleep, my HR drops to 50. Last week my doctor (his nurse practioner—he is never there) stated they did not want to give me any medication to calm my heart rate because with it going so low when I sleep, that it could bottom out. All of a sudden this week (today), they have decided to put me on Verapamil to calm my heart. I am scared to take anything and scared not to take anything. They say I have IST. I have been stressed and depressed (over life) for several years, I have insomnia, bad headaches almost daily. I was medicated for 3yrs with 3 different asthma meds, then found out I didn’t even have asthma (could that have hurt me?). I used to be very active in sports, but had to quit after 6yrs because I could not breath. I am at a loss of what to do.

January 29, 2013 at 8:25 am
(46) Bertha says:

I diagnosed myself as having IST after endless endless Google searches. Initially I went to the doctor with symptoms of heart racing, couldnt breath etc and he diagnosed Sinus Tachy. I refused beta-blockers and started searching. Im now in the second week of 5mg Coralan (ivabradine). With my home HR monitor I can see a difference in my resting HR – which always was between 92 en 100 dropped to between 76 and 84. In all the studies they say you can expect a reduction in HR of 10bpm. And the beauty of the medicine is that I have no side effects. I’m still to scared to start an exercise routing .though ….
I still get the “spikes” when I stand – will research more on POTS which is linked to IST. Good luck.

January 29, 2013 at 10:14 pm
(47) Katie O says:

I was recently diagnosed with IST, my resting heart rate is around 98 but fluctuates from 43-175. I have had many episodes of near fainting and one actual fainting episode. My heart feels like it is going to jump out of my chest and I can never catch my breath. As well, I have developed migraines! Fun times! Lindsaey 38 you mentioned taking Ivabradine….how were you able to obtain that drug? I am in the works trying to get it as I have read it seems to be the only thing to really work! I am currently taking 40 mg of nadolol and 10 mg of lorazepam but would really like to move on from that as it is not fixing my chief complaints. If anyone knows how to get Ivabradine please do post! Thanks

February 2, 2013 at 9:58 pm
(48) Scott says:


If you can’t understand why trying a pressor makes sense and is a reasonable thing to try in the face of this disease, then I’m quite glad you are not my physician. One wonders if your doctoral work is in divinity or a related field.


February 11, 2013 at 8:21 pm
(49) jane says:

I was diagnosed when I was 38 with IST. It started when I was at work.I left work and went to my Dr. My resting heart rate was 170, he sent me to the er and was given meds and sent home. I have had 3 ablations and I am worse today.I have tried so many meds with no relief ,so I no longer take any.I get terrible pain in my chest, get out of breath, get very dizzy and I am so fatigued that I can’t do a lot. My life has changed forever. 3 years ago my son was also diagnosed with IST and has had 3 ablations as well.

February 28, 2013 at 6:07 pm
(50) maria says:

I was diagnosed with IST at about 37, I am now 42. I have had symptom my entire life. I take a low dose of a beta blocker. I feel much better on the BB but right now Iím trying to up my running but itís not easy! I can run about 10 minutes a time at a slow jogging speed 4.0 on the treadmill. I am fairly short so itís still actually a jog, but itís taken me 5 months just to get to this! ugggg! Running with this condition for me is the pits. I am determined to push myself I HATE the limitations of this condition. I know some people cannot exercise at and there was a time I could not either so maybe I should just be thankful.

Iím wondering how exercising is for other people with IST ?

March 19, 2013 at 12:16 pm
(51) Jessica says:

I have had Tachycardia for two years since I had a very bad Ebstien Barr Virus infection ( mono). It has been call IST and Postural Orthostatic Tachycardia Syndrome or POTS. I have tried Midodrine and could not take the side effects and confusion it caused me. I live with taking 50-100mg of Metroprolol now, but physical activity is still hard and I get winded easily. I am very active and do two different martial arts and I want to be able to run for more that 3 min at a time. I get breathless and have chest pain when my heart rate stays over 180 for too long which happens fast. With my med I can function normally for normal activity. My bp is naturally low so the med makes me so tired! I just tried cardizem and it was no better than a piece of candy. There is a new med coming out that my cardiologist is going to try me on after its on the market for about 6 months. I am going to an autonomic dysfunction clinic in June, since it is not my heart (tecnically) that is causing the issue. Pots is an autonomic dysfunction. My heart is perfectly healthy. Docs around where I live just don’t know much about this. And have had them ask if I’m anxious or depressed. I’m te least anxious and depressed person ever. I’m a psych nurse, I know all about these things. Any other info/advise? Have you heard about POTS?

June 27, 2013 at 2:43 pm
(52) Erin says:

I was diagnosed with this after a less than fun hospital stay back in February in which they did EVERY test in the book (and told me I had a 99 percent chance of having a blood clot in my lungs, which I didn’t THANK GOD). IST seemed like a fairly nice settlement after being tested for cancers and blood clots. Im 23 years old, and I used to dance 50+ hours per week for 18 years of my life. My heart was obviously in great shape when I so active. My mother suffers from the same condition (even though she wont get tested for it), and so thats obviously where I got it from. We always made fun of her for being so nervous, but that just goes along with the fast heart beat. I’m sure the onset of mine was from stopping my extremely athletic life after college. I am currently trying to lessen my symptons with exercise therapy, it is no way easy, but I know my body better than anyone else, and I know when I am pushing it too hard. I have read many successful stories of both people with POTS and IST that used exercise therapy to help manage their heart conditions. My doctor and I agreed to try to abstain from any more medications that I need to be one, because unlike this article says I actually do have anxiety and sleeping problems. It wasn’t until the IST set on that I was really ever tired without having to take a sleeping aide. Its been a very interesting year for me to say the least.

September 18, 2013 at 8:46 pm
(53) Debi says:

I saw a cardiologist yesterday as my pcp was tired of hearing me complain about rapid irregular heart beats. I was told it was probably anxiety, even though I have a very strong family history of high bp, diabetics, high triglycerides and cholesterol. I was was on lisenopril 20 mg and my bp was well controlled. The cardiologist at first was going down the anxiety route too, but after an EKG he saw IST. My pulse was 144 after sitting in his office for an hour. He ordered an echo for next week and I am mount the 24 he urine test today. Now the channel blocker has lowered my pulse rate to 76, but now my BP is running 123/83 tonight which is higher than when I was on lisenopril. They are definitely too quick to say anxiety. On a side note, my farratin levels have been over 700 and the GI Dr said I don’t have Hemochromotosis, so my PCP just ignores it.
I am 50 and want to know what it takes to get a dr to listen to you?

September 22, 2013 at 4:53 pm
(54) Hector Hammersley says:

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October 8, 2013 at 8:56 am
(55) taulant says:

hi i am taulant from kosovo i first had tachycardia when i was 14 and i went to an cardiologist he said i was fine after my heart beats relaxed im 20 now and every year it happend to me once but this year my heart beats went to 221 i was really scared now my doctor says that my heart is in great condition and it is still growing i am seeing a psychiatrist and i still dont feel good i dont know what i have can you please tell me what should i do because my life is really bad at this time thank you

November 4, 2013 at 5:59 pm
(56) jodi says:

I was diagnosed with I.S.T a couple of years ago, i’m a 22 year old man, every day is different, some good, some bad, its definitely a challenge but staying positive about lift is very important. I’ve been on procoralan (ivabradine) for well over a year now, fluctuating between 10MG a day and 7.5mg a day. I have noticed some weird symptoms now and again, i would say 50% of the day my heart rate is within acceptable rates (usually around 70-85 when resting) however in stressful situations were adrenaline enters the systems even if its only a tiny amount this medication does nothing. It affects the sinus node alone, unlike beta blockers. And as opposed to what doc’s say, it does have side affects, including withdrawl because i’ve tried switching my doses around now and again and noticed chest pains and a significantly higher heart rate.
Some side affects i’ve noticed very occasionally include shortness of breathe, visual disturbances (not dizzy but balance) a really powerful heart beat, but at a normal rate. These side affects are generally not too bad at all, although i’ve never tried a different med so i have no comparisons! I can’t drink alcohol like i used to, i limit it to 2-3 beers less than 6 times in a year, i avoid cannabis completely, i used to smoke this quite regularly but stopped shortly after developing tachy. Exercise is possible but not comfortable. If i jogged for half a mile my heart rate would remain hover at 100-120 bpm for at least 30 minutes. I’ve also noticed that my body is much more sensitive to environmental conditions. A warm stuffy train in the underground on a cold winters day is shite. Flying is a real nervy experience even short flights across the UK (30-40 minutes) I would say its had a huge impact on my life and it’s really frustrating that there is a real lack of research into this condition to try and help sufferers because in many ways its as debilitating as some more serious conditions

December 17, 2013 at 2:19 pm
(57) Sue says:

My daughter got IST at 16. She had been an extremely active, athletic teenager but after waking up one morning with IST has suffered for the last 5 years with a resting heart rate of 150 bpm that would jump to 200 with the least bit of exercise. She took metoprolol to reduce it to a resting heart rate of 100 but it would still jump to 180-200 with little effort so she has been unable to significantly exercise. In addition the metoprolol made her tired and she was prone to passing out particularly in the heat.
After much personal research we investigated trying an ablation. This procedure is extremely unreliable for correction of IST. If they are not aggressive with the ablation it is not successful but if they are too aggressive they end up destroying the sinus node to the point where you need a pace maker which is not a good thing for a 20 year old to have if you can manage your illness with medication. The surgeon that was consulted on ablation agreed to write a prescription for ivabradine which is a medicine that has been used in Europe for many years and was designed strictly for treatement of IST. I purchase it thru a Canadian pharmacy who obtains it from international pharmacies. It has been a miracle. She now has a resting heart rate of 70 and can resume all her old activities with no rapid heart rate symptoms. There have been no side effects from the drug. It is like we turned back the clock 5 years to the life she had before IST. This drug is not FDA approved and probably never will be because it is not economically feasible to market in the US for the limited use. I strongly encourage anyone dealing with this problem to ask their cardiologist to prescribe this drug. Your insurance won’t pay for it but you will have your life back.

January 12, 2014 at 3:16 am
(58) Valene M. Shipman says:

May I simply say what a comfort to uncover someone that actually understands what they’re talking about on the web. You certainly realize how to bring an issue to light and make it important. A lot more people should look at this and understand this side of your story. I was surprised you are not more popular since you certainly possess the gift.

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