Figure 11

Aortic distensibility. The cyclical pumping nature of the heart places a heavy demand on the distensible characteristics of the aortic tree. A, During systole, the aortic tree is rapidly filled in a fraction of a second, distending it and increasing the hydraulic pressure. B, The distensibility characteristics of the arterial tree determine the pulse pressure (PP) in response to a specific stroke volume. The normal relationship is shown in curve A, and arrows designate the PP. A highly distensible arterial tree, as depicted in curve B, can accommodate the stroke volume with a smaller PP. Pathophysiologic processes and aging lead to decreases in aortic dis-tensibility. These decreases lead to marked increases in PP and overall mean arterial pressure for any given arterial volume, as shown in curve C. Decreased distensibility is partly responsible for the isolated systolic hypertension often found in elderly persons. Recordings of actual aortic pressure and flow profiles in persons with normotension and systolic hypertension are shown in panel A [11,12]. (Panel B Adapted from Vari and Navar [4] and Panel A from Nichols et al. [12].)

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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