What Is Aortic Dissection? Causes, Symptoms & Why It’s Rare

A different blood pressure on the opposite arm? Think aortic dissection. The wall of the aorta splits, blood tracks into a false lumen, and that channel pressurises, swelling and squeezing the true lumen while the flap can drape across a branch vessel. Cover the branch to one arm and that limb loses flow, which is why you can feel a strong radial on one side and a weak or absent one on the other. It’s also why a blood pressure difference between arms matters: it’s not a faulty cuff, it’s blood b