If husband has afib then he probably qualifies for an implanted Defib.
I had one put in 4 years ago for "peace of mind"
Talk to your cardiologist. If he will not do it, immediately get a second opinion.
IMO Implanted defib is the gold standard for AFIB.
When I worked in the hospital (22 years) I saw hundreds and hundreds of them implanted and NEVER saw a complication.
Please get one soon.
Carrying a portable is second best and a distant second If you have a AED and go out to dinner or take a walk in the forest etc then you have to carry it with you. If you are far away from it you may as well not have it.
An implantable will help the cardiologist keep better track of your arrhythmia's as it stores the info on any anomalies in your rhythm for over 6 months for your cardiologist or any ER to view. This will help with your treatment in a strange town.