A doppler ultrasonographic observation of interventional postural alterations on shear rates in peripheral arteries

Abstract

Introduction and Aim: Drastic life style changes had resulted in increased reports of morbid atherosclerosis in young adults which is potentially a serious inflammatory condition which causes arteries to become harder and blocked with lipid accumulation known as plaques or atheroma. In the present study, effect of changes in posture on the resting shear rate (SR) was studied in arteries of both extremities. Materials and Methods: A cross sectional observational doppler ultrasound study was done in 30 healthy subjects, who satisfied a pre-set inclusion and exclusion criteria. The mean blood flow velocity (BV) and diameter were measured for both brachial arteries and femoral arteries in supine, sitting with leg fully extended, sitting with leg flexed at 90o, standing with and without slight head tilting of 10o postures after resting the subjects for 10 minutes in between each posture. The SR in various postures were calculated and tabulated. The data was statistically analysed using independent ‘t’ test and one-way ANOVA. Post Hoc test was applied for analysing statistical significance of SR in between postures. Results: The femoral artery showed significantly lower SR (P<0.001) in all the postures studied when compared to brachial artery. On comparing posture within brachial and femoral artery by applying one-way ANOVA with Post Hoc test, only femoral showed significant difference in SR between postures. Conclusion: The postural effect in SR of arteries in lower limb may lead to alterations in the endothelium of arteries resulting in increased atherogenicity as compared to upper limb arteries.