Arterial stiffness: insights from Framingham and Iceland.

PURPOSE OF REVIEW: To examine the putative measures of arterial stiffness and the mechanisms of adverse effects of stiffness on blood pressure and target organ damage using data from comprehensive hemodynamic profiles obtained in the Framingham Heart Study and the Age, Gene/Environment Susceptibility-Reykjavik Study.

RECENT FINDINGS: Once thought to be a consequence of longstanding hypertension, recent evidence suggests that aortic stiffness antedates and contributes to the pathogenesis of hypertension and target organ damage in the heart, brain, and kidneys. Carotid-femoral pulse-wave velocity (CFPWV) has emerged as the reference standard measure of aortic stiffness and a powerful predictor of cardiovascular disease risk. Augmentation index, a putative measure of arterial stiffness and wave reflection, has complex relations with stiffness and risk. Recent evidence suggests that wave reflection, which is a normal consequence of impedance mismatch between compliant aorta and stiff muscular arteries, is protective and limits the exposure of target organs to potentially harmful pulsatile energy. Aortic stiffening produces impedance matching that reduces wave reflection and exposes the microcirculation to excessive pulsatile stress, resulting in microvascular target organ damage and dysfunction.

SUMMARY: CFPWV provides a powerful new tool for risk stratification and elucidation of the pathogenesis of target organ damage in hypertension.