Pulsatile flow: A critical modulator of the natural history of atherosclerosis

Atherosclerosis is a systemic process with multi-focal distribution which progresses or regresses in an entirely independent manner within each patient. The low and oscillatory shear stress along with the geometrical particularities of the coronaries modulate an atherogenic microenvironment in susceptible to atherosclerosis regions and determine the disease's rate of progression. However, the atherogenic effect of flow pulsation remains ambiguous. Since the pulsatile nature of the blood constitutes the major generator of the oscillatory shear stress, one could hypothesize that this physiological process might exert a synergistic effect to low SS by facilitating the lesion progression. The heart rate determines directly the frequency of flow pulsation; therefore, its reduction could potentially decelerate the progression of atherosclerosis by alleviating the local atherogenic hemodynamic environment. This perspective might constitute an insight into the beneficial role of heart rate lowering agents with most significant representative the beta-blockers, which have been proved quite efficient anti-atherosclerotic drugs. (c) 2006 Elsevier Ltd. All rights reserved.