I can only talk in terms of the UK CAA but I have had pretty much the same as you and am nearing an initial decision from them. In summary I had:
- Stroke with no residual after effects
- PFO discovered during investigations
- All other investigations normal
- PFO sealed
As a rule of thumb, expect to wait a minimum of 1 year before they will even consider certification. If they do re-certify you, the best you will get is a multi-crew limited medical (called OML in UK). Fine for airlines, no good for things like single pilot etc.
You need to get all the tests possible to cover every base - wait until 3 months post PFO closure then something like... repeat bubble echo (to prove sealed), exercise ECG, 24hr ECG, Bloods.
Get copies of EVERYTHING - all medical reports, CT scans, MRI/MRA - the lot. You need to hand the authority as much information as possible in order to allow them to assess your case. Centre piece to this will be an in-depth report from your consultant Neurologist which covers key topics such as -
1) Cause, Treatment, Prognosis
2) Risk of recurrence (hint: must be in the 1% area ideally)
3) Risk of seizure
4) Medication, long term outlook etc
Even after all this, be prepared for them to say it's a perm disqualification. The key sticking point is usually risk of recurrence/seizure.
The fact you had a PFO is actually good for the case as it gives a reason for the stroke (albeit a currently controversial one in the world of medical opinion)
Do your research. Lots of info on the internet, etc.
Don't give up. Stay positive. Good Luck.