Griffin was ordered to completely rest for a couple of weeks before later being cleared to return to full training with Bath as he recovered from a diagnosis that is not regarded as a permanent condition.
“At the time, I obviously didn’t know what it was,” said Griffin.
“After the game, I had lots of check-ups and found out what had happened. I had to take lots of medication.
“I had two weeks off exercise, apart from walking my dog, before slowly getting back into full training.
“I’ve got to keep an eye on it. Symptom-wise, it’s something I’ll monitor. It’s a bit like concussion.
“I’ll report any symptoms to the physios and I’m not going to lie about it because it’s my heart. You can’t take any risks.”
Griffin has been picked by Warren Gatland in his 35-man squad for Wales’ autumn internationals against Fiji, Australia and South Africa.
He has linked up with Wales this week, alongside fellow tight-head props Keiron Assiratti and Henry Thomas, and hopes to feature in the opening game against Fiji on 10 November in Cardiff.
Griffin, who impressed when starting in Wales’ two Test defeats against Australia last summer, is just grateful to be back playing.
“It’s made it more clear to me now that all I want to do is play rugby,” said Griffin.
“Not being able to do anything for two weeks shows you not to take it for granted.”
