The Relationship of Plasma Norepinephrine Levels and Aortic Distensibility in Elderly With Isolated Systolic Hypertension

The present study evaluated the relationship of plasma norepinephrine (NE) and aortic distensibility (AOD) in a group of elderly patients with isolated systolic hypertension. Aortic distensibility was calculated as AOD = 2 × (Δ aortic diameter)/diastolic aortic diameter) × (Δ aortic pressure). Results indicate that the aortic diameters were significantly increased while the diastolic blood pressure and heart rate were decreased, in response to combined α- and β-receptor blockade (labetalol). However, we found that AOD was not significantly related to plasma NE. We therefore conclude that AOD can be increased in elderly hypertensives by α-β-blockade, as has been found in younger patients, but plasma NE is not a useful marker for AOD in this population.