What do you suggest if my husband suffers from atrial fibrilation. who is the top authority on this condition in the uk?

First...: Anticoagulation and rate control. An echo should be done to help determine the cause, and likeliness of successful conversion to sinus rhythm. If a fib is well tolerated, cardioversion or ablation could be considered after at least 1 month of therapeutic anticoagulation. If he is having significant symptoms from the atrial fib, then earlier cardioversion could be offered after a negative TEE