your consultant will advise you inform the DVLA , once you are back firing on all cylinders he will give you a clean bill of health and you can then inform Swansea.
wish him a speedy recovery from me, my brother ended up with a triple by pass and was off the road for 8 months but most of that time was waiting for the operation, a stent will soon see him back to normal.
A relative had a stent recently and is fit and well now, so try not to worry. He was advised to keep off the road for one month though and we did have to run him around. Out with the bus pass and the train timetable! He did not have to inform DVLA or surrender his licence, just tell the insurance company. This was instructed by the surgeon and i guess that varies depending on the person and the severity of the heart attack. Wishing him a speedy recovery.