Aim: It is known that high-fat diet, induce hypercholesterolemia, diabesity, hypertension, deterioration of arterial wall, both morphologically and mechanically. Mechanical changes include thickening of arterial wall, alteration of arterial elasticity, contraction of smooth muscle, increase in sensitivity to pharmacological stimulation and increase in arterial viscoelasticity, i.e., arteriosclerosis. The present study aimed to investigate the effect of combined high and low frequency sonication accompanied by high- dose atorvastatin administration and discontinuation of cholesterol-rich diet on mechanical parameters of atherosclerotic carotid artery.

Methods: In this experimental study, the rabbits’ common carotid arteries were injured perivascularly by liquid nitrogen, followed by a 1.5% cholesterol- rich diet for eight weeks. Histology results showed severe stenosis (>70%) and neovascularization in the rabbits’ arteries. Then, the lesion region treated using extracorporeal low- level combined high (1MHz, 2 W/cm2) frequency and low (150 KHz, 0.2 W/cm2) frequency unfocused ultrasound accompanied by high- dose atorvastatin (5 mg/kg/day) administration and discontinuation of cholesterol- rich diet in treatment group. Arterial mechanical parameters were evaluated in the groups using Vessel Tensile Strength Test Device.

Results: Results showed a significant reduction in the mean value for shear elastic modulus, resistive indices and a significant increases in the mean value for radial strain, compliance, distensibility in the treatment group compared with the other groups (P<0.05).