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.

[Endothelial Dysfunction in Patients With Takotsubo Syndrome and its Role in Acute and Long Terms Of the Disease].

Aim      To evaluate the endothelial function using an Endo-PAT2000 instrument before and after mental stress tests in patients with Tacotsubo syndrome (TS) during acute and long-term periods and to compare the obtained results with laboratory markers of endothelial dysfunction (ED).Material and methods  This study included 45 patients with TS (mean age, 63.5±13.7 years) and 40 healthy volunteers (control group, CG). All patients of the main group during the acute period (first 7-14 days) and long-term period (at 1 and 2 years), as well as CG subjects, underwent evaluation of the endothelial function with an Endo-PAT 2000 instrument, and the reactive hyperemia index (RHI) was determined before and after mental stress tests. Also, concentrations of endothelin 1 (ET-1) and numbers of circulating endothelial cells (CEC) were measured after a two-year follow-up of TS patients.Results During the acute period of disease, all TS patients (n=45) had ED: RHI was below the threshold level of 1.67; furthermore, 42 (93.3 %) patients retained a lower RHI following mental stress. At one year (n=40), 16 (40%) patients showed ED at rest along with a significantly increased mean RHI. Mental stress produced at one year was associated with ED in 28 (70 %) TS patients. At two years (n=44), resting RHI was lower than normal in 19 (43.2 %) patients. Mental stress tests performed at two years were associated with ED in 29 (65.9 %) patients (RHI ≤1.67). Only 10% of CG subjects had a lower-than-normal RHI, which was significantly less than in the main group of TS patients during the acute and long-term periods (p<0.05). Mean values of laboratory markers for ED also were significantly different between TS patients during the long-term period of disease (n=41) and CG subjects (n=40; p<0.01).Conclusion      During acute and long-term periods of disease, most of TS patients had impaired vascular reactivity both at rest and during mental stress. The laboratory markers of ED, ET-1 and CEC can be used in clinical practice for evaluation of the risk for TS.