Dynamics of human coronary arterial motion and its potential role in coronary atherogenesis

Mechanical forces have been widely recognized to play an important role in the pathogenesis of atherosclerosis. Since coronary arterial motion modulat es both vessel wall mechanics and fluid dynamics, it is hypothesized that c ertain motion patterns might be atherogenic by generating adverse wall mech anical forces or fluid dynamic environments. To characterize the dynamics o f coronary arterial motion and explore its implications in atherogenesis, a system was developed to track the motion of coronary arteries in vivo, and employed to quantify the dynamics of four right coronary arteries (RCA) an d eight left anterior descending (LAD) coronary arteries. The analysis show s that: (a) The motion parameters van among individuals, with coefficients of variation ranging from 0.25 to 0.59 for axially and temporally averaged values of the parameters; (b) the motion parameters of individual vessels v ary widely along the vessel axis, with coefficients of variation as high as 2.28; (c) the LAD exhibits a greater axial variability in torsion, a measu re of curve "helicity," than the RCA; (d) in comparison with the RCA, the L AD experiences less displacement (p =0.009), but higher torsion (p=0.03). T hese results suggest that: (i) the variability of certain motion parameters , particularly those that exhibit large axial variations, might be related to variations in susceptibility to atherosclerosis among different individu als and vascular regions; and (ii) differences in motion parameters between the RCA and LAD might relate to differences in their susceptibility to ath erosclerosis. [S0148-0731(00)00405-2].