Variability of Measurement and Feasibility of Assessing Changes in Brachiocepahlic Atherosclerotic Plaque After Acute Coronary Syndrome.

Aim      Analysis of inter- and intra-study variability of changes in the atherosclerotic plaque (ASP) total height and total area, the main quantitative indexes that were planned to be used in the present study for assessment of the atherosclerotic load of carotid arteries.Material and methods  The incidence of recurrent cardiovascular complications (CVC) within 1 year after acute coronary syndrome (ACS) ranges from 7-9 % (in studies) to 34 % (in clinical practice). This indicates insufficient efficacy of traditional approaches to secondary prevention of coronary heart disease. We proposed a study to test a hypothesis that the dynamics of ASP parameters in carotid and subclavian regions can serve as an alternative criterion for the adequacy of secondary prevention after ACS. The analysis was performed on subgroups of main study participants. These patients had ACS of any type documented by coronary angiography with an ASP confirmed by ultrasound of the brachiocephalic arteries (BCA) during the index hospitalization. BCA ultrasound was performed to analyze the inter- and intra-study variability of BCA atherosclerotic load, the ASP total height (Hsum) and total area (ASPTA), in 20 and 24 patients of the main study, respectively. Results of the repeated ultrasound were evaluated in 30 patients of the main study after 6 months of follow-up.Results The inter-study variability of each index was significantly higher than the intra-study variability which was consistent with results of previous studies. The intra-study variability of Hsum was 0.10 (95 % confidence interval, CI - 0.23-0.44) mm and ASPTA, 1.05 (95 % CI, - 0.54-2.63) mm2. The variability values were considerably smaller than the changes for 6 months: Hsum, 0.92 (95 % CI, - 0.64-2.49) mm and ASPTA, 3.67 (95 % CI, 0.42-6.91) mm2, although the difference did not reach statistical significance. The above results were obtained at an early stage of the study during the adaptation of specialists to the protocol.Conclusion      The study results suggest a possibility of a fairly reliable assessment of the dynamics of quantitative indexes of carotid ultrasound 6 months after ACS.