A Study to Correlate Carotid Intima Thickness by B-Mode Ultrasonography in Patients Documented with Coronary Artery Disease

AIM OF THE STUDY: To study the IMT of the common carotid arteries and correlate with documented coronary artery disease. PATIENTS AND METHODS: The study was conducted in subjects with history of coronary artery disease in the past and who presented with acute coronary syndrome. After detailed history and examination, investigations were carried out as per our protocol. The sample size was 100, with 70 in the case group and 30 in the control group (matched).B-mode ultrasonography scanning of the carotid arteries was performed and measurements were made at proximal, middle and distal segments of the common carotid arteries. Univariate analysis was used to confirm the significance of the variables and multiple regressions were used to predict the risk, based on significant variables RESULTS: The total study sample consisted of 100 subjects, of whom 70 were cases and 30 were controls. The case group comprised of a total of 70 patients with a mean age of 58.72 years. In the control group of 30 patients, the mean age was 62.73 years. In the study group, 77.1% (n=54) were males and 22.9% (n=16) were females. In the study group, 51.4% (n=36) were smokers compared with 13.3% (n=4) among the control group (P=0.001 vhs). In the study group, 20% (n=14) had diabetes while this was 13.3% (n=4) among the control group. In the study group, 52.96% (n=37) had hypertension while 16.7% (n=5) had hypertension in the control group (P=0.001 vhs). The mean total cholesterol among the study group was 197.4mg/dl while in the control group it was 175.9 mg/dl. Thirty-two percent of the patients with CAD had anterior lateral wall ischemia, 21% had anterior wall, 21% lateral wall, 19% inferior wall and 7% unstable angina. The mean carotid IMT in the study group was 0.923 ± 0.123 and in control group it was 0.689 ± 0.051 (P=0.001). The mean carotid intima thickness was significantly high in the case group as compared with the control, and the P-value was highly significant. CONCLUSION: The carotid IMT was found to be higher in patients with coronary artery disease, and there was a statistically significant difference between cases and controls. Thus, our study shows that carotid IMT is a marker of atherosclerosis that is strongly associated with risk factors and can be used as a surrogate marker in the prediction of atherosclerosis in coronary artery disease. As it is easily reproducible, carotid B-mode ultrasonography is a safe, non-invasive and reproducible procedure that helps in the early identification of clinical coronary artery disease.