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264156 tn?1206990594

Anyone else here with IST or other sinus tachycardias?

Hey there! I'm a 24 year old who has been dealing with a new diagnosis of Inappropriate sinus tachycardia. It has been rough, but have gotten it somewhat under control my meds. One of my cardiologists believes I should strongly consider having my SA node ablated and a pacemaker put in, but I'm not in so much of a rush. :)

I was just wondering if there is anyone else out there who has IST or another tachycardia syndrome and would be willing to share your symptoms, meds, lifestyle changes because of the illness and anything else. Thanks in advance!
17 Responses
144586 tn?1284669764
Tachycardia is defined as a heart rate above 100. That being said, I have had a heart rate of between 106-110 for decades. My lifestyle has been pretty outrageous. However I sold my T-10 parachute and am making some acomodfations in my old age. I also no longer perform low-level aerobatics.
144586 tn?1284669764
Try magnesium glycinate BEFORE even considering the abl;ation procedure. If your cardiologist has not suggested this find another cardiologist.
257552 tn?1404606154

In problems that I wrestle with, dysautonomia seems to rear its ugly head as a possible cause or contributing factor to my woes, although I have not been diagnosed with IST.

Surprisingly, reading about IST due to my own curiosity about your problem, I was astonished to discover that some correlation may exist to IST and Dysautonomia. (Not a lot of links, you need to pry, but nevertheless, there are articles).

In addition, one article that I read said that since Electro Physiologists favor the dysfunctional SA Node theory, and have not seriously considered Dysautonomia as the cause, it is possible that ablations are being done when they may not be warranted. In addition, the article said that although 80% of the ablations are successful for IST when initially done, the IST recurs in the majority of the patients within a few months. (Again, the article said this, I make no assertion one way or the other).  I don’t know if the article was referring to the total ablation of the SA node and replacement with a Pacemaker or lesser forms of ablation concerning the SA Node.

Try Wikipedia and research Dysautonomia. Also a site called About (dot com) and research IST.

Be healthy.
264156 tn?1206990594
Hey there thanks for your reply! Yeah I've done some SERIOUS searching in regards to IST. I'm on the fence about what I should believe. The main time I have problems is when I go from sitting to standing, and also when I am faced with a stressful event or situation. My SA node seems to be super sensitive to any release of adrenaline and my HR skyrockets.

I was curious to see what others had to say... I hope to find someone with the same diagnosis as it is very frustrating and lonely...not too many people are actually labeled as having IST. I'm suprised you found a success rate of 80%. I was given a 40-50% rate, which in my opinion...I think I'll pass on those odds. :)

Caregiver~ What is the significance of the magnesium? Have you had any luck with it?
84483 tn?1289941537
Be vary of cardiologist that suggest such a drastic treatment for IST such as ablation of the sinus with insertion of a pacemaker. IST is nearly always a  benign but uncomfortable  condition, you are very young consult with more EPs. Sometime IST improve with age, get more opinions . Good luck.
84483 tn?1289941537
Just mention I have a similar all my life including bouts with PVCs, I take the beta blocker atenolol with no adverse effects, at least not the dreaded ones and I take a high doses 100mg total daily. My resting heart used to vary between 90-115 in the morning least excitement or effort 120-150 range, after meals always over 100 bpm, sometime 110-120 for 2 hours, though usually at night would go down into low 60s for hours, until tachycardia actually woke me up most of the time 90-110 bpm , though 90 would not be defined as tachycardia it is still high.On atenolol my resting heartrate averages about 64 bpm, excitement probably no more than 90-100 and responds almost perfect to exercise with me still able to reach over 85% of my max predicted heart after 12 minutes on a stress test.My heart has been deemed normal ,just sensitive to adrenaline and basically hyperactive heart which when you are aware make its alots worse because it cause anxiety , they are many out there with even faster rates that are totally unaware they have them.
264156 tn?1206990594
Thank you so much for sharing your story!

A little bout me: I am a 24 year old otherwise healthy individual. On June the 4th I decided to drink a super caffinated coffee (for the first time) to get energy to move in to our new house. BAM next thing ya know I'm in the ER with my heart going 180+ It continued on like this for months, fluctuating from 110-170 or so with very little exertion. The FRUSTRATING thing is prior to this I was in SUPER shape, working out intensely most days of the week, eating healthy, no alcohol tobacco never touched a single street drug in my life yada yada yada. And now here I am with this crazy heart. I ended up in and out of the ER with an uncontrolled and very symptomatic tachycardia. EKG's only ever showed sinus tach. Potassium was always on the low side. After seeing 4 different cardiologists and EP they decided I have IST. I've been on a very low dose of beta blockers, 12.5 only once in the a.m and it has done WONDERS for me. Sounds extremely low compared to your 100, but I've always been very sensitive to medications. So now my resting pulse is around 60-70, upon standing though it goes up to 80-100 but then it figures things out and goes back done to about  70-80. The problem before I took the medicine was it never seemed to know when to quit! Now I'm gradually working out again, nowhere near the intensity I was doing before but I don't mind. I'm just thankful to be able to do what I can do. I have noticed here lately that when my bb wears off after about 6 hours or so I tend to get some palpatations. I never take another pill because I only tend to have the tachycardia in morning/afternoon. Evenings the borderline tachy is manageable.

That's me in a nutshell!
257552 tn?1404606154

Of the Beta Blockers, I believe that Atenolol has a half life of approximately 6 hours. Others, such as Nadolol, have a half life of approximately 24 hours. If you are on Atenolol, or another Beta Blocker with a short half life, this may be why you experience more palpitations after that amount of time.

But Beta Blockers can apparently be a double edged sword, they can actually cause an arrhythmia in some people. Myself, I don't notice significant difference between Nadolol and Atenolol, except that my heart seems to beat harder towards evening when I am on Atenolol, the rate is still below 65 (at rest) regardless of which one I take. (Atenolol 50 mg in the morning, 25mg at night, or at other times, Nadolol 20 mg in the morning and 20 mg at night).

Also, some patients respond better to one form of Beta Blockers than another. In addition, Atenolol is a Selective Beta Blocker and Nadolol is a non-selective Beta Blocker. The non-selective Beta Blockers may contribute to difficulties with breathing in some individuals, such as asthmatics.

What are you taking?

264156 tn?1206990594
Hey there, thanks for your reply!

I'm taking metoprolol, very low dose of 12.5 in the am only. My doctor wants me to work up to 25 twice a day, and then 50 mg twice a day. I am EXTREMELY hesitant/skeptical about taking medication. I'm not a complete naturalist, but would chose natural methods (meditation, relaxation, biofeedback) over meds any day. I went 2 months trying to control this on my own. I was able to somewhat get it under control naturally, but was still having too many fluctuations. The medication has been amazing.

How long have you been on the bb's? What was the reason you went on them if I may ask?
84483 tn?1289941537
Thanks for sharing also. I'm glad the beta  blocker metoprolol is apparently helping you. have you ever had an EP study to determined the exact cause for your IST, sometimes concealed accessory bypass tracts , also called concealed accessory pathways can masquerade as sinus tachycardia until discovered in an EP study, one doctor mentioned this as the possible cause of my tachy also , ihaver never had an EP study, as I'm well controlled with atenolol that is actually supposed to be long acting but not as long acting as once thought.I actually take 25mg 4 times daily to make sure it works properly and so far so good. If if ever get tacycardia again especially with the betas I'll probably have an Ep study as to determined the exact mechanism but no ablation until I'm advised accordingly, sounds as though you're on the right path .Take care and be well.
264156 tn?1206990594
I actually went in for the study and the cardiologist tried to be sneaky and take my pulse as we were talking (acted like he was trying to reassure me and touch my hand) Then mid sentence he was like "well your going pretty fast right now, I'd like to hook you up to an EKG" At that point I was going around 140-160, stress tends to spike it up. He watched my rhythm for about 10 minutes and then decided to call off the procedure. He said he was 80 percent sure it was purely a sinus tach solely from the SA node. He didn't feel as though the procedure was necessary. They recommended the beta blockers and to follow up in a month. Being the stubborn person I am, I didn't take the meds for over two months as I was trying to "heal" myself.

I wish you the best of luck and hope the beta blockers maintain their effectiveness for the both of us!
219704 tn?1338612705
I was diagnosed with IST earlier this year after years of struggling with it's symptoms.
Unlike most people, my IST comes and goes. The longest continous IST cycle for me was about 3 to 4 weeks. My mother has IST also and has been on Beta-blockers since the early 80's.
Blocadren works the best for her.

I also have PVC's, NSVT, and sinus arrhythmia and was diagnosed with hypokalemia in the mid 90's.
None of the arrhythmia's seem to concern my EP/Cardio, though I've been offered numerous beta-blockers. I did try Metoprolol which made me super fatigued and Sectral increased my PVC's by hundreds daily. After the Sectral, I've opted to go drug free, at least for now.

What works best for me as far as the IST goes: stress reduction, plenty of sleep, increased fluids (blood volume), liquid magnesium and a higher sodium diet. (As long as your otherwise healthy, raising your sodium level temporarily shouldn't be a problem) I also stay away from anything that I know I have food intolerances to like, tomatoe sauces, MSG, Aspartame, heavy glutens, and red wines. Over-eating is also a big trigger as well as becoming dehydrated and it takes at least a week for me to recover. :(

On a positive note, in some people, IST improves or resolves over time, so hang in there....
I certainly wouldn't opt for an pace-maker at your age and am astounded that one of your cardiologist suggested it right up front....As you probably know, ablations for IST doesn't always mean an pace-maker!

Be well!
Avatar universal
   I am 19 an i also have IST. i was diagnosed about a year ago. the symptoms that i get is occasional dizziness and fast heart rate. I sometimes feel like i will faint and sometimes feel short of breath and also get palpatations. at first docs thought it was a different arrythmia but i went in for ablation and they found out it was IST so they didnt ablate due to it being the SA node. Ive been on verapamil since feb. and it has worked well for me ive had fewer symptoms since then. Just wanted to let you know that your not alone :)
264156 tn?1206990594
Thank you so much for taking the time to reply!

Celeste~ I also have sinus arrhythmia and hypokalmia. I wonder if there is some sort of link between the IST and hypokalemia... So how are you doing now that you are drug free? I would LOVE to not be on medication but it was getting to the point where I needed to give it a shot. I went 2 months trying to control it on my own. I improved it tremendously but it wasn't good enough. Your list was wonderful thank you so much. I have noticed a lot of people take magnesium, do you know the significance with this?

Angiebabie~ Thank you as well for replying! It's so good to know I'm not alone! Was verapamil the only med you have tried? I'm not too familiar with that one, I'll have to look it up. So what is your pulse range while on medications?

I wish both of you the best of luck!
255722 tn?1452550141
I do not suffer from your condition and have no direct advice.  However, I wanted to say that you should go ahead and take the medication. There is no shame in relying on the medication to stabalize your condition, and then, once your body has adjusted you could try the homeopathic/natural avenue again.  I suggest a happy medium. It is likely that you will do well with lower doses of medication since you rarely take meds, and since you are so dedicated to naturalistic healing.  

Biochemistry is a funny thing.  While we are full of feedback mechanisms that can often be moderated with great concentration, sometimes it takes a jumpstart to get our chemicals in check before nature can settle down.

Good luck to you. And if NOTHING ELSE, I'm glad you found the forum and now realize that you ARE NOT ALONE.  That is one of the biggest contributors to relaxation ever when dealing with an arhythmia.
264156 tn?1206990594
Thank you so much for your kind words! They really mean a lot. I totally agree, I think I may have needed a jumpstart. My doc wanted me to work up to 50 mg twice a day and here I am taking just 12.5 mg in the morning and I feel as though it has made a huge difference. I am very sensitive to meds, and a lot of docs don't fully understand that. I always take less than what the recommend at first.

I am very thankful I found this forum. If I would have only found ONE person with IST it would have helped tremendously.

Avatar universal
Verapamil is not the only med that i tried. First i tried toprol and it just didnt cut it for me i just kept having more and more "attacks" so the doc put me on verapamil and now ive been realyl good. on the meds my heart rate is between like 76-88. without it those its high 90's or a little over a hundred.
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