I think you'll find that your 'average' cardiologist/specialist can say whatever he wants, if he isn't approved by your CAA then you'll need to find one who is. Pressure your CAA into telling you exactly what needs to be done to licence you.
They will probably also tell you that they're merely a 'regulatory body' and they don't have a medical suggestion. If you tell them that if you'd had a heart attack they would come up with something-eg a stent on the affected artery-so how about a suggestion now. In all likelihood the will insist on an angiogram-the gold standard they'll tell you-before this. Don't waste your time ( and money) on exercise ECG's, blood tests etc, which (from experience) they may well describe as 'merely screening tools' unless they ask for them. Usually anything to do with the heart is of a high priority to the medical profession so you'll be seen quit equickly
I'm sure there is a way forward but you will have to take the ball and run with it. It's too easy for a CAA to say 'No' (Nyet!) and not to have any risk on their shoulders. They can then go home in the evening knowing that they've done a good job and kept aviation safer having denied you a licence. Meantime you're no nearer to the flight deck. Nine months is not a bad average time to jump through all the hoops but you'll have to do all the pushing for a result in that time. That would include a mandatory period grounded after an angiogram
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