Authors:

M Matangi¹ , M Cases¹ , D Brouillard¹ , A Johri² , ¹Kingston Heart Clinic - Kingston - Canada , ²Queen's University - Kingston - Canada ,

BACKGROUND. Screening for atherosclerosis is an important method for assessing cardiovascular (CV) risk. Our data with carotid imaging shows a normal a carotid is associated with a very low 10-year CV risk of 1.6%. Even a low risk carotid still predicts a favourable outcome, 5.6-7.0% CV risk over 10 years. Increasing plaque burden as assessed by either total plaque area (>25mm2) or plaque score (>1) is associated with increasing CV risk, ranging from 20% to >30% over 10 years.
PURPOSE. This analysis was performed to estimate the prevalence and severity of carotid disease in men and women presenting for stress ECHO, with no prior documented evidence of CV disease.
METHODS. Data was collected from October 3, 2011 to January 22, 2019. Male patients aged 40-70yrs and female patients aged 50-75yrs undergoing stress ECHO underwent a screening carotid examination prior to the test. This involves only 2-3 images on each side to include, the CCA, carotid bulb and ICA. Maximal CCA IMT is measured using an automatic edge detection method, plaque score is calculated using the Rotterdam method and plaque area is measured in the carotid bulb and ICA bilaterally. Total plaque area being the sum of all area measurements. Apart from age criteria, patients were also excluded if they were diabetic, already taking a statin, or had a previous history of any vascular disease. A low-risk carotid was defined as a maximal CCA IMT <1.00m,with a plaque score of "0" or "1" providing the total plaque area was <25mm2. An unpaired t-test was used to detect differences between means and the Fisher’s exact test was used to detect differences between proportions. A p value of <0.05 was considered statistically significant.
RESULTS. There were 1683 patients, 1175 females and 508 males with a mean age of 60.9 ± 7.4 years. Of the 1683 patients 1058 had evidence of carotid plaque (62.9%), 368 males (72.4%) and 690 females (58.7%). 726 patients were classified as low-risk and 957 patients were classified as high-risk. See Table 1.
CONCLUSIONS. A brief screening carotid examination prior to stress ECHO reveals a large percentage of both men and women who have evidence of atherosclerosis, of which 56.9% are high-risk. These patients could be identified while in the ECHO laboratory. The patients could then be offered guideline therapy with statin therapy and low dose ASA.