Tachycardia and risks of becoming pregnant, and risks of ablation procedure?

[Tkaya]

I am 30 years old, and was diagnosed with Tachycardia in November 2005 (after having my first child in March 2005). I also have a prolapsed mitral valve (but have been told this is a minimal problem). I have been taking Metprolol and it is working. I had an Echo, MRI, and other tests. From the results they think it is a signal creating its own route..? I am not really sure what I have. They are not sure if it is from the lower or upper chambers. I have recently decided to book a cardiac ablation (with an EP study)procedure this year, as I would like to have more children. My cardiologist stated to me that I do not "need" to have the ablation, and I could remain on Metoprolol for an indefinite period of time. He also says that the only risk to the baby would be a lower heart rate, and possibly a low birth weight. I am not really sure how he can say this, since I have been reading that the side effects or metoprolol have only been tested on animals (are there any articles you could suggest on animals or humans to read?). However, I would like to have another child in the next year or so, and I am unsure about the risks. My questions are as follows:

1) What are the risks of this procedure and success rate of a cardiac ablation?
2) If I were to get pregnant (and decide to not get the procedure done) what are the risks to the baby, to myself (also can I still get an epidural?), and how can anyone really say what the risks would be to my child (since it is only animal tests that have been done)?
Any information you can give me would be helpful.

Tkaya

[CCF-M.D.-MJM]

Hello tkaya,

Sorry my reply is late.  I was away from the clinic and my computer crashed.

Congratulations on your baby!!!  It is not uncommon for people to have their first tachycardia during pregnancy -- the classical is for atrioventricular nodal reentrant tachycardia (AVNRT).

Your doctor correctly gave you the option for medical therapy or ablation -- both are first line treatments.  He is also correct that the side effects that we quote for beta blockers is low fetal heart rate at birth and low birth weight.  It is virtually impossible to include pregnant women in research studies -- for very good reasons.  Is there a possibility it could do something else, yes, but the the only relatively common side effects are fetal bradycardia and low birth weight.  you won't find much else out there on it.


1) What are the risks of this procedure and success rate of a cardiac ablation?

It depends on what the cause is.  AVNRT with radiofrequency ablation in good hands has a 98% succes rate, cryo has a 92% success rate.  The risk of death from an SVT ablation is very uncommon (less than 1:1000).  The risk of needing a pacemaker is also very low but the risk depends on the type of tachycardia (AVNRT the risk of pacer is <1%).  The risk of bleeding are generally less than 2%, risk of stroke depends on whether the tachycardia is coming from the left or right side of the heart.  In general, ablations are very safe procedures.  Talk to your doctor about the risks and benefits and make sure you are comfortable with them.

2) If I were to get pregnant (and decide to not get the procedure done) what are the risks to the baby, to myself (also can I still get an epidural?), and how can anyone really say what the risks would be to my child (since it is only animal tests that have been done)?

If you have a normal heart and an narrow complex tachycardia, the risk to you and your baby are very low from not having the procedure. It is safe to have an epidural.  Unfortunately the animal studies are all we have.  I am sure there are case reports of people who didn't know they were pregnant and took beta blockers throughout pregnancy.  The other way to look at it is -- beta blockers are one of our oldest cardiac medications.  If complications were happening frequently, it would have a black box warning.  I think I understand what you are looking for -- you want a yes or no answer.  My wife would want that as well if she were in the same situation.  Unfortunately, the best we can  say is what you already know.  It has increased risk of fetal bradycardia and low birth weight.

I hope this helps.  Thanks for posting.

[fearfactor]

Hi, I am 38 weeks pregnant right now (having my c-section on Sept. 1 - yay!) and have been on Toprol XL throughout my pregnancy.  I take 12.5 mg every other day for heart palpitations.  According to the ultrasounds I've gotten, my baby girl is healthy and normal.  It seems Toprol hasn't had any bad effects.  I hope your ablation is successful - if I were you, I'd likely do the same thing just to be rid of the problem!

[bama jane]

read through a lot of the old posts on this site.  there are many regarding  pregnacy and tachy arrhythmias, it may be helpful to you.

[ngkk]

Hello -  I have svt along with pvcs - just wanted to give you my expirience with toprol xl and pregnancy  -  I have had 2 children on toprol xl 25mg and have had absolutly no problems - both children were well over 8lbs (so no low birth weight) - I also have breastfed both - which I'm currently still doing with my 9mth old - also have had no problems. But if I was you I definitly would go for the ablation - I have had 2 ablations but they can not find anything wrong with my heart ( no extra pathways)  which is discouraging because I would love to live symptom free.  Good luck with your ablation and future pregnancy!

[cristabelle]

Hello, if it is of any consolation, I was on atenelol (25mg per day) through almost the whole pregnancy with my one child. My OB said it would be preferable if I could refrain from taking it the first trimester and so I went almost 3 months, but it was tough.  I was also somewhat older than you are so your youthfulness in your favor it would seem.  
Like the other poster mentioned I had a healthy 8lb 6 oz girl and no bradycardia in my child.  She is a healthy 7 year old gymnastic fanatic now!

I look forward to the DR. response as this is interesting to me. This is only my experience, I am not a physician or am not providing any advice or counsel.

cristabelle

[CollegeGirl143]

i dont think there is any known risk of being on beta blockers while carrying on a pregnancy. I had a successful ablation back in april and it was the best thing ive ever done for myself. Risks of the procedure are very minimal, less than 1% chance of serious complications (but degree of risk does vary depending on what part of the heart needs to be ablated) and success rates vary depending on what type of arrhythmia you have, but they are generally very high. good luck!

[Tkaya]

Thank you everyone for your posts and advice. It made me feel alot better. I think I am going to wait for the procedure, the timing is horrible (my 18 month old), and it is not absolutely necessary that I have it. Furthermore, I would worry about the possible complication, risks, and the possibility of it not even working. Plus 1:1000 isnt very good odds to me! I am more likely to win the lottery but 1:million would be better. I am just a chicken!

After hearing from other women that have given birth to healthy children on similar medication eases my mind quite abit, and Metoprolol seems to be the safest beta blocker out there.  

Thanks again.