Review Article

Vascular Stiffness and Increased Pulse Pressure in the Aging Cardiovascular System

Figure 2

Schematic representation of pulse pressure amplification. Pressure tracings from the brachial artery and central aorta are shown, from a young individual with a highly compliant vasculature tree (left) and from an old one with stiff vessels (right). Despite similar brachial blood pressures, central blood pressures vary considerably. In young individuals, 𝑃 1 (which coincides with systolic blood pressures) marks the outward traveling blood pressure wave, while 𝑃 2 represents the arrival of the reflected pressure wave in diastole, augmenting diastolic blood pressure, and coronary filling. Pulse pressure augmentation in old, stiff vessels leads to a significant increase in 𝑃 2 as compared to 𝑃 1 , as wave reflection occurs earlier and faster, leading to an augmentation in systolic blood pressure. Augmentation index is calculated as the difference between the second ( 𝑃 2 ) and first ( 𝑃 1 ) systolic peaks (delta 𝑃 ) as a percentage of pulse pressure (see [23]).
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