Combination anti-arrhythmics

[Nik]

Had a patient on a ward I've been working on who's been in for a while, and who was on a beta blocker and amiodarone for AF, with digoxin added during his stay. Just wanted to get some thoughts on using all three of these together for AF. NICE guideline mentions specialist referral for amiodarone consideration if pts are on digoxin and beta blocker but not the other way around. Incidentally, he was only on dig for a short while and he's now back on amiodarone and the beta blocker.

[_Rob_]

Its one of those combos you see but always sits uncomfortably (well for me anyway). Guess you've got to remember the obvious digoxin-amiodarone interaction. Using the triple combination, there is an increase risk of AV node block hence the potential for heart block through to worse case asystole. Then again sometimes there are few other options, patient is already loaded with amiodarone, they have a BP that won't support an increased B-blocker dose and you need to manage the AF.
More importantly, you need to manage the underlying cause of the AF (over the original diagnosis and treatment). This in the acute setting is more often than not infection, toxic patients often get AF, so ensuring the patient gets appropriate antibiotics is essential. Once the infection is treated, the need for the additional digoxin is no more and the patient can return to their normal prescription.
Guess it is a bit outside the NICE guidance?

[Nik]

Thanks Rob, was on the same ward again this morning and had a more thorough read of his history. Originally came in with COPD exacerbation but during his stay his AF went a bit haywire. After loading him up with digoxin, he was quickly titrated to 125mcg digoxin within 1-2 weeks (couldn't find dig levels) but it was soon stopped, presumably as his K+ dropped to about 2.9 and he complained of feeling sick with poor oral intake. Seems ok now as his HR is about 65 on bisoprolol and amiodarone. Just one of those combos that look a bit unusual.

[crit care]

as long as they monitor everything, i'm assuming it was on cardiology advice as well, or the doctors sought cardiology advice. Often they do weird things, and its a risk:benefit of treating the AF and not treating it!