Frequent episodes of tachycardia

I am a 41 year old female (and a registered nurse for 20 years) - healthy, normal weight,routinely exercise, non-smoker, take no medications, live in a good healthy environment, once or twice/wk have a glass of wine or two at night, and drink only 1 or 2 cups of coffee in the morning. I am married and have two children 14 and 16..everyone is healthy.  I do have a history of systemic lupus which has been in complete remission since 1999 with zero problems.  Other than that, negative history cardiac-wise.  I have no anxiety or panic issues, and to top it off, my husband is a dostoc and is stumped by this problem and wants me to get it checked out.

Given that, at random times I have begun to regularly experience episodes of tachycardia that come on taking my heart rate up to 140-170 bpm (from a normal of 70-80).  This will happen in the morning, afternoon, at night, and sometimes will wake me up in the middle of the night as it makes me feel slightly short of breath. It will feel bounding.  It will last an hour or two...sometimes all day..then it will go away.  I notice it immediately as it feels very strong and bounding.  It will happen on days when I haven't had alcohol for days, and it will happen 12 hours after a cup of coffee, so it doesn't seem to be alcohol or caffeine related. Oddly enough, the fast heart rate will sometimes come on after eating. The worst is when it comes on in the middle of the night. It is very annoying.  What is the chance this could be Wolf Parkinson White syndrome or some random rhythm issue?  I have had hormonal testing for estrogen, LH, thyroid and all are within normal parameters.  Is next step an EKG as I presume?  Given the history, what do you guess this could be?

Thank you for your thoughts.

[Michael J. McWilliams, M.D.]

To be honest, it sounds most consistent with panic attacks or inappropriate sinus tachycardia.  Other causes of SVT usually do not happen in the middle of the night.

If the symptoms happen everyday, I would do a 24 hour monitor.  If it happened several times per month, I would do a 30 day monitor.  The key to determining what the rhythm is seeing how it initiates, terminates, and the general characteristics of the tachycardia.  It is sometimes not clear from a 30 day monitor and an EP study is necessary to determine the exact cause and if it can be fixed.

If your heart rate decreases suddenly back to normal, that is often AVNRT, AVRT (WPW) or atrial tachycardia

If it decreases slowly, that is more likely sinus tachycardia.

The answer is usually in the rhythm strips.

[Lindsay67]

Thanks for your thoughts.  I had not included this previously, but my husband is also a cardiologist, and I have often joked that anything short of a MI doesn't get attention in this house. :)  (He will laugh that I went online to post a question) So, he has been stumped as well, but does not think it's panic attacks or anxiety as to my persona and not in my nature.  I went in and had ekg yesterday which was normal and am going back later to have this 24-hr holter removed.  I did have several episodes of fast hr and at 2am awoke to hr approx 160 and slightly short of breath.  I kept an accurate journal. So, you are right and the rhythm strips after analysis should tell us what is going on.  Sure it is minor, but an inconvenience none the less.  
Thanks.

[Michael J. McWilliams, M.D.]

That is pretty funny.  I hope you get an answer (that is easy to fix or ignore).