Bradycardia after IST ablation

[The_beat_goes_on]

I recently had a failed ablation (due to sedation issues and proximity to the phrenic nerve) for IST and SVT and atrial flutter. They redid the ablation successfully with an epicardial balloon and general anesthesia. Fixed the SVT. Fixed the atrial flutter. And maybe over modified my sinus node for the IST. I went from going up to 210bpm at rest and NEVER under 120 to today. It's been three months since the ablation and now I feel like I traded the dizziness and SOB that comes with tachycardias to a dizziness and lightheadedness / SOB with a lower heart rate.  I have fainted once so I'm on a 30 day 24/7 monitor and it beeps about 20 times a day and night when my heart rate goes below 40 and hovers around 45 throughout the day.  It scares me because it's always the same when Im up and around. I start feeling a pounding in my chest, get light headed-- gray out a little and BEEP.  the monitor auto triggers. Its gotten down to 30bpm and I don't seem to go above 70. Even when doing strenuous activities. I have a stress echo soon and I'm so nervous. What if my heart rate doesn't raise above 70???  I'm not even 30 years old and I don't want to commit to a pacemaker. But I knew it was a risk with the sinus node modification.

If my heart rate doesn't raise appropriately during the stress echo, is it likely that between that and the monitor results, my cardiologist will want me to go for a pacemaker?

Has anyone else had a sinus node modification for IST and ended up with bradycardia?

[MichelleP_3811]

I am sorry to hear you needed a pacemaker but better that then the life you were living.  Glad to hear things are going well for you.  Take care.

[The_beat_goes_on]

Just an update to this ... my heart rate eventually dropped into the 30s (I was alternating between junction and ventricular rhythms), never sinus, with pauses and I did end up with an electric heart beat and am doing great with it. (:

[The_beat_goes_on]

I honestly was almost expecting to leave my last ablation with a pacemaker, because of the risk and warning.  I couldn't function with my IST before, and my symptoms made my ep dr feel the risk of a pacemaker was warranted.  I just didn't expect to almost be in the same place on the opposite end of the spectrum.  

I'm not sure what my pr interval is, I haven't seen .. my ep dr just says "very short" ... I'm also not sure if I'm in sinus rhythm or not.

[abc85]

What is your pr interval now?  Ablations for IST have a high risk of needing a pacemaker which is why often EP's are hesitant to do them.  There is also a high risk that although it may initially be successfully, the tachycardia returns later.  With the shortened pr interval and what your HR is now, one thought that comes to mind is possibly that your sinus node is not functioning and you now are in a junctional rhythm.  You can still have a p wave with a junctional rhythm but you typically have no pr interval or a very, very small one.  The p wave could also be found after the qrs, but it doesn't sound like this is the case for you.  As to whether or not your doctor is going to recommend a pacemaker, I can't really say but with the symptomatic bradycardia, they may suggest it.  Good luck!  

[The_beat_goes_on]

I forgot to mention that since the ablations I have a shortened pr interval-- which might be why I fainted and is another reason for the stress echo. To possibly unmask an accessory pathway.