Wolf
It has been known for years, that the central BP ( that blood that comes directly out of the left ventricle into the aorta ) is often at a different pressure to that of the arm or peripheral BP, and old physicians and cardiologists could gauge this by feeling the peripheral pulse with the palm of the hand......google " water hammer pulse and Corrigans Pulse.
Does it really matter in the long term, strokes and heart attacks which pressure is taken? No, at the moment, there is only one relevant study and that shows that the end result is no different whichever pressure is taken.
At the moment it is a good research too, but little else.
A rupture of the aorta or an aneurysm of the aorta in the part closest to the heart is rare...a GP will probably have never seen one.
Do not change your medication at all, in my opinion, but if you are concerned consult your GP.