Carotid IMT and Haemodynamic Indices in Evaluation of Atherosclerosis in Hypertensives

Purpose: To evaluate carotid haemodynamic indices and intima media thickness as sonographic markers of atherosclerosis for possible use in PHC clinics of resource limited countries.Methods and Materials: This was a cross-sectional study involving 130 hypertensive patients and 130 age-matched controls, all underwent carotid Doppler examination using Mindray DC-8 ultrasound machine. Blood sample was taken after an overnight fast for lipid profile and FBS. The Framingham Risk Score (FRS) was calculated from patients’ information. The data were analysed using SPSS version 20.0. T-test was used to test the difference between variables. Pearson correlation was used to determine correlation between duplex finding and FRS. p<0.05 was considered statistically significant.Results: The mean age of the hypertensive is 50.20 ± 10.30 and the mean age for control is 49.39 ± 9.89. The mean Carotid Intima-Media Thickness (CIMT) is significantly higher in hypertensives compared to control. Common Carotid Artery (CCA) Pulsatility Index (PI), CCA Resistive Index (RI), Internal Carotid (ICA) PI and ICARI were not significantly different between hypertensive and control. It was observed that the value of carotid haemodynamics indices increases with increasing age in the hypertensive but the relationship of increasing age and haemodynamic indices is less clearly demonstrated in the control. There is a strong correlation between CIMT and FRS in the hypertensives and only in ICA there was a correlation between haemodynamic parameters and FRS.Conclusion: CIMT appears to be the best sonographic marker of atherosclerosis. Though carotid haemodynamic indices correlate less clearly than CIMT, there appears to be a gradual increase in the carotid haemodynamics with age, particularly in the hypertensives.