This is very common. Oral infections travel very quickly through the bloodstream and into the heart. I'm not sure whether dental scaling would really warrant prophylactic measures. Anything involving extracting or cutting into the gums, jaw definitely would require antibiotics prior. If your Dr/Dentist is still prescribing you antibitoics prior to treatment then I would think it's safe to assume that it is still a necessary precaution.
The premedication requirements have just changed drastically and you should check with your dentist to find out if it is necessary any longer to be premedicated.