Is it uncommon for someone, who has suffered a recent, mild heart attack, to be given a full written release back to normal working conditions by their doctor 3 days later (nothing came up in the Ekg or scan but he is visibly weaker and hoped to be able to take a week for recouperation)?

Shouldn't all hospitals policies (at least in these types of procedures) err on the side of caution? I know this person and he is a hard working older vet who isn't trying to get a free vacation. Any thoughts? Thanks.