(For a class 2 medical holder) you don't need to see a 'CAA approved' cardiologist. Any consultant cardiologist should be able to provide a report for your AME. You'll likely need to pay for the consult however and any tests needed to meet the CAA requirements (it's unlikely to be able to cover this fromt he confines of a routine NHS clinic appointment for example). Sure those on the old list of CAA approved cardiologists will be familiar with the requirements but you needn't be restricted to that short list. if you take the current flow chart with you, any cardiologist will be able to determine if you fulfil the requirements (provided they have access to the relevant information about you) and prepare a report on it.
The current flow chart is at
http://www.caa.co.uk/docs/2499/Coron...tervention.pdf
Happy to help further as needed. I occasionally do this kind of review for fellow aviators (in my capacity as a cardiologist!)
JC