how many attempts at cardioversion are recommended.....

[Lisa-K]

  I had written several months ago with questions regarding my 59 y.o. father's recent diagnosis of atrial fibrillation (thanks again for the response/advice!!)
  His doctor had attempted cardioversion, after starting my dad on coumadin and digoxin.. and while he was able to get him to a sinus rhythm for a few seconds it was unsustainable...he was placed on cordarone, by mouth,(i believe 200mgs/day, after an oral loading dose...) and a second attempt at cardioversion was done: unsuccessfully, save a second or two in a normal rhythm...
  my father is overweight..cholesterol was high...though he has lost 40lbs so far on his own low fat diet...lowered his chol. significantly already.
  Walks on the treadmill an hour a day....Could his weight have been a factor
  during the cardioversion(despite the fact that he did have some transient response ....)?
  His doctor believed that since he was able to get my dad into a NSR, that was unsustainable...the likelihood of him maintaining a normal rhythm with any additional attempts at cardioversion was slim. He put my dad back on digoxin and coumadin....
  Echocardiogram done at the beginning of this heart "trouble" was basically normal..though my father did mention some enlargement (which side or chamber, I do not know...)but that this enlargement was slight, and not a concern to his doctor. Had a stress (thallium) test after the second cardioversion: normal...
  I realize it is of great benefit to get the heart into a normal rhythm...
  When, however, do you say enough is enough, regarding further attempts (chemical, surgical,etc...)and continue as my father is ...on dig and coumadin?...He feels fine..has never been symptomatic.
  I realize that every patient is different..but perhaps you have some ideas, about what might be done for someone like my dad...and any statistics regarding the likelihood of getting someone like him into a normal sinus rhythm..
  thanking you very much, in advance...
  Lisa K.

[CCF Cardio MD - MTR]

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Dear Lisa, thank you for your question.  You ask a number of insightful questions regarding the treatment of atrial fibrillation which I'll try to answer.  Your father has been treated per the standard recommendations for atrial fibrillation.  The digoxin is to keep the heart rate slow (<100) while the coumadin "thins" the blood to prevent clots from forming in the left atrium.  After the first attempt at cardioversion failed, cordarone (amiodarone) was used which is the best anti-arrhythmic drug available today.  Since cardioversion failed on amiodarone, it is unlikely that he will be able to stay in sinus rhythm and the amiodarone was appropriately stopped.  You are correct that maintenance of sinus rhythm is better in the long-term, but since your father appears to have a normal heart, atrial fibrillation should be better tolerated.  For example, a patient with congestive heart failure would benefit hemodynamically from sinus rhythm whereas your father may face theoretical alterations in the geometry of the cardiac chambers with long-term atrial fibrillation, but he should not have serious complications from this.  One cause of atrial fibrillation that should always be considered is hyperthyroidism, which his cardiologist probably has already excluded.  There are experimental surgical and catheter-based procedures to eliminate atrial fibrillation (the so-called Maze Procedure) that have variable success and don't appear to be indicated for your father since he is basically asymptomatic.  Thus, I think your father is being appropriately treated and I agree that future attempts at cardioversion would most likely be futile.  I hope you find this information useful.  Information provided in the heart forum is for general purposes only.  Specific diagnoses and therapies can only be provided by your physician.