The name of the deceased, a 55-year-old heavy-set South African national, is being witheld until it can be confirmed that the man's family and embassy have been notified.
Police were told that the man, who was reportedly staying in Karon by himself, had paid a visit to a clinic attached to his hotel, after complaining of chest pains.
The man then reporedly fainted while he was waiting to pay for his treatment. Police have not said what kind of treatment, if any, the man had received at the clinic, but confirmed that the man had been dead for no less than two hours by the time they arrived to Patong hospital.