BP reading on different arms

I monitor my BP at home, I usually use my left arm and have a fairly normal reading 125/70
but when I use my right arm the reading is high 145/76..why is this?
and which reading is the more accurate?

[SassyLassie]

Blood pressure is usually different on both arms, but, to be honest, I have not heard of it being as much of a difference as you posted. I would ask a doctor as I am just not sure. Also, here is a link to our heart forum, maybe someone there will know more, I am stymied, to be honest. Here is what I found while doing a search on "Doctor's Lounge Web Site", hope it makes sense:

An acceptable inter-arm systolic blood pressure difference is 10mmHg. The difference in your case seems to exceed that.
I would suggest before delving into the causes of this condition to have a doctor examine your blood pressure. Note that you should be rested for 5 minutes before the reading and that you should use an appropriate sized cuff.
If a doctor does indeed conclude the blood pressure difference is high (he may need to confirm this with a doppler), an underlying condition should be sought. Congenital conditions in the differential diagnosis include aortic coarctation and thinning of 1 of the subclavian, axillary, or brachial arteries. Acquired arterial conditions include aortic dissection, atheroma, thrombus, embolus, and extrinsic compression (as might be seen in association with a mass in the upper chest).

In this case you should have a contrast-enhanced CT of the chest to effectively delineate among the possibilities mentioned above. A vascular ultrasound would be helpful as well, but the CT would better show an extrinsic compression.

Here is the link to our heart forum:
http://www.medhelp.org/forums/Heart-Disease/show/72

[opus88]

thx so much for the time to reply, I will do some more reading on the web site.