Pregnant - strange heart episodes/palpitations

[ashling835]

Hi, I am 32 and 11-12 weeks pregnant. Generally very healthy and fit.

Since I was a teenager, I have had random episodes of tachycardia, where my heart feels as though it's not quite beating properly and gets 'stuck' around 120-140 bpm. It feels very different from when my heart beats that quickly at other times, such as from exercise or exertion, in that it creates an almost pressure bubble type feeling in my chest, a feeling like I need to bend over and can't do anything as well as what I can only describe as a super scary, doom type feeling (like something is very seriously wrong). These episodes can last for hours, and I have been into hospital several times as a result. The drug Adenosine has no effect, even at high doses. I have been given Valium to rule out stress/anxiety as a cause, but this also had no impact on my heart rate. Cardioversion did restore a normal heart rate. There don't appear to be any triggers as it often started whilst I was sleeping.

I have been evaluated by a cardiologist and had an EP study done and essentially, it seemed that no-body really knew what was causing these episodes because everything appears normal. My heart appears to be in a normal sinus rhythm during the episodes as monitored in the hospital. These days, I have learned that by holding my breath for as long as possible before passing out, I can cause my heart to do one big beat, and this seems to reset it back to normal preventing me from needing to go into hospital. 'Bearing down' did not help.

Fast forward to today. I've had 2 previous pregnancies with no particular cardiology concerns. 4 days ago now, I suddenly started having what feel like short episodes of the above condition, but far more frequent. For example, previously I would have an episode every 6-12 months and then it might last for hours without my intervention and breath holding techniques. Now I am sometimes having several instances per hour, but they all seem to be self-resolving within 5-10 seconds. At times they wake me from sleep and anxiety seems to exacerbate both the frequency and intensity.

I went to emergency 3 nights ago, but whilst I was in the hospital, for 4 whole hours, I didn't have a single episode. I was very anxious at the time and hospitals scare me so my heart rate was elevated, but everything felt normal to me. They did test everything whilst I was there though and everything came back perfect - blood pressure, all bloods, saturation levels, sinus rhythm etc. They did give me fluids and MgSO4 to try and help. I have been referred back to my cardiologist and I will try to get in to see them asap, however I was wondering if anyone has any idea of what this could be I would appreciate your feedback/advice.

Kind regards,