QUANTITATIVE CORRELATION OF CAROTID ARTERY INTIMA MEDIA THICKNESS WITH SEVERITY OF OCCLUSIVE CORONARY ARTERY DISEASE

BACKGROUND Patients with established stroke and coronary artery disease (CAD) have relatively thick carotid intima media compared to general population. There are several studies reporting the role of carotid arteries' intima media width as an independent risk factor for stroke and CAD. It shows diffuse ongoing atherosclerosis process affecting coronary and carotid as well as other arteries of the body. Carotid intima media thickness is a good and valid marker for atherosclerosis and has the potential to detect cardiovascular diseases. It reflects the collective impact of atherosclerosis in blood vessels independent of the underlying cardiovascular determinants. We wanted to assess of intima media's thickness of carotid artery and its association with CAD and stroke and correlate carotid artery intima media thickness with severity of occlusive coronary artery disease as evidenced by coronary angiography, quantitatively. METHODS One hundred and fifty subjects from the indoor and outdoor departments of the hospital were recruited in the present case control study. A convenient sample size of fifty was taken in each group. In the first group 50 patients of CAD, in the second group 50 patients with known CVA (Stroke) and the third group with 50 healthy controls were included. After confirming diagnosis of stroke and CAD, patients and control subjects were subjected to measurement of intima media width bilaterally (posterior wall of distal CCA). To see the extent of the disease, patients with CAD underwent coronary angiography. B-mode ultrasound scan (7.5 MHz probe) was used for measurement of intima media thickness and to see ulceration, stenosis of lumen, and plaques Doppler color scan was used. Statistical analysis was done by using SPSS software version 16. Mean, standard deviation, frequency, Chi Square and one-way ANOVA with post hoc test were used. A p value of less than 0.05 was taken as significant. RESULTS In present study, three study groups did not differ in age, male to female ratio, and in other socio-demographic details to avoid confounding factors. Average carotid intima media thickness in healthy controls was one millimeter; in stroke group, 1.3 mm and in coronary artery disease was 1.3 mm. Carotid IMT is a determinant of atherosclerosis increased value of the width is seen in CAD and stroke affected individuals. As the Carotid IMT value goes above 1 mm chances of stroke and CAD would rise. When the number of blood vessels involved in CAD increases, average CIMT also increases. This concludes that more severe lesions in coronary vessels imply more severe atherosclerosis. Coronary intima media thickness is helpful in quantifying coronary atherosclerosis. CONCLUSIONS It is concluded that the non-invasive procedure of carotid B-mode ultra-sonography is suitable for use as a surrogate end point to measure atherosclerotic burden in the subjects because of its easy applicability. Thus, Carotid IMT is a useful, simple, cost effective and non-invasive tool to evaluate severity of atherosclerosis in patients with stroke and CAD. The pre-occlusive phase is the potential stage to retard the atherosclerosis by timely intervention as primary prevention.