The Difference of Mean WSS Value on The Carotid Bifurcation and The Medial Segment of Common Carotid Artery Using Vector Flow Ultrasonography in Hypertensive Patients at Prof Dr. I.G.N.G Ngoerah General Hospital February-April 2022

Abstract

Background : Hypertension is a risk factor for atherosclerosis which increases the risk of stroke. Transitions in blood vessels such as bifurcations are associated with changes in the velocity and pattern of blood flow that decrease wall shear stress (WSS) and is believed to be a risk factor for atherosclerosis. Shear stress on the common carotid artery also decreased with increasing blood pressure. This study aims to determine the difference of mean WSS value on the carotid bifurcation and the medial segment of common carotid artery using vector flow ultrasonography in hypertensive patients. Methods: This study used a cross-sectional design with the research location at the Radiology Installation of Prof. Dr. I.G.N.G Ngoerah Hospital Denpasar in February-April 2022. The sample of this study was hypertensive patients who came to the Radiology Installation of Prof. Dr. I.G.N.G Ngoerah Hospital and met the inclusion criteria as many as 32 people. The examination was carried out by a consultant of head and neck radiology, using an ultrasound device with a linear transducer probe that has a probe frequency range of 3-9 Mhz. Results: The average age of the sample in this study was 50 years, with 9 males (28.1%), 23 females (71.9%). The results showed that the average maximum WSS value on the carotid bifurcation (3.37±0.96) Pa, the mean value (1.15±0.45) Pa, while the average maximum WSS value on the medial segment of the common carotid artery (4 ,41±1.45)Pa, the mean value (1.78±0.54)Pa. The average maximal and mean WSS value on carotid bifurcation were lower than the medial segment of the common carotid artery in hypertensive patients (p<0,05). The results of multivariate analysis on WSS values after controlling for confounding variables, obtained the average maximal and mean WSS value on carotid bifurcation, remained lower than the medial segment of the common carotid artery (p<0,05). Conclusion: there were significant differences in the mean wall shear stress (WSS) of the carotid bifurcation and the medial segment of the common carotid artery in hypertensive patients. Suggestions that can be done next are in facilities that have vector flow ultrasonography facilities, it is recommended to measure the WSS value in hypertensive patients as additional information as a predictor of atherosclerosis