after flecainide fails what is next

please see the following  HX from previous post to this forum:
SVT and cardioversion
Nov 01 by jresmith
Was started on Flecanide 100 mg BID after CV #3.  Lasted 25 days, then back to 160BPM, increased doseage of Flecainide to #300mg did not convert SVT. CV#4 at 50 J to NSR with inverted p wave.  Increased Flecainide to 150 BID, this lasted 15 days, then back to 160BPM. CV#5 at 50J.
back to 58BPM as of now.  Dr. is considering Solatol, since I have no other heart problems(previous Mitral valve repair with Maze for PAFIB, both sucessfull).  I have Asthma which is triggered by non cardiac specific BB's, but can handle Zebeta. BB effect of Solatol may not be tolerated.  He is willing to do another abalation, but seems to think it is a multifocal problem best handled with drugs.  Questions are:
1. I have noticed that prior to each time I have to be cardioverted it seems the tightness in my chest is a little worse, even though heart at the same rate and O2 sat at 99+%.  Does the cardioversion affect the heart after repeated CV's.
2. If Solatol is not tolerated is Amiodarone the only other choice? and what are the long term side effects of the drug.  With the past hx of drug's not working on me, would you expect Amiodarone to be successful? Are there any other drugs that we can try?
3. If drugs do not work, what are the odds that another abalation will work. Dr. thinks he got the first pathway, said it was the atypical variety.
4. If SVT cannot be stopped, will complete abalation of the AV node stop the problem, even if it leaves me pacemaker dependent, or will it just start another round of problems. Do the atria remain in AT forever and what does this do to longeviety. In other words, should all drugs be exhausted before pacemaker dependence is chosen.
5. What are the problems associated with pacemaker dependence, other that being on Coumadin forever, and having the unit changed every 5-8 years. What is the quality of life with pacemaker dependence.  

[Michael J. McWilliams, M.D.]

1. No, cardioversion do not irreversibly affect the heart.
2. I would not put someone your age on amiodarone unless an ablation is not an option.  I would use flecainide first, propafenone second, tikosyn third, sotalol forth, and amiodarone as last resort.

There is an extensive discussion of amiodarone side effects at this site:
http://www.drugs.com/pro/amiodarone-hydrochloride.html

3. if you have had a MV repair and a PVI, this is probably a scar related or left atrial flutter.  This is not as likely to be a right sided procedure.  This is a procedure that should only be done in experienced hands because it is likely to require a transseptal puncture and extensive left atrial ablation.  In the right hands, the ablation probably has a 70% success rate.

4.  Someone your age, a pacemaker and AV nodal ablation is an absolute last.  Some people do not tolerate pacing well and the AV nodal ablation is not reversible. If it comes to this, look for an experienced center in left sided ablations.

The atria will probably remain in atrial tachycardia/flutter if not cardioverted.

Drugs are not likely to work well if this is a left atrial flutter.  Drugs first, ablation second, pacemaker/ablation last.

5. You would be pacemaker dependent.  Some people have symptoms with pacemakers and the AV nodal ablation is not reversible.  Athletes tend to not like being pacemaker dependent because they can't seem to work out as hard unless their rhythm was intolerable before the device.

Even with the pacemaker, if you don't have heart failure, hypertension, diabetes, age greater than 75 or history of stroke, you would not need coumadin (this is up to you and your doctor).
There are risks of infection that are cummulative -- if you are young and need a generator change every 8 years and you live another 60 years -- that is 7 device changes.  7 devices changes x a 2% risk of device infection with each change out is a over 14% risk of infection for the life of the device.  In my opinion, you should try to avoid the pacemaker option.  There is a risk of stroke with the left sided ablation procedures as well though.  You will need to weigh the risk/benefits and how they apply to you.

I hope this helps.  Thanks for posting.