The Frequency of the Minor Polymorphisms in the CYP2C19, VEGFR-2 Genes, and Clinical Outcomes in Russian and Buryat Patients with Acute Coronary Syndrome.

Aim: To determine the differences in the frequencies of polymorphic variants at the rs4244285(*2), rs4986893 (*3), rs12248560 (*17), loci of the CYP2C19 gene, and the rs2305948 locus of the VEGFR-2 gene in patients receiving clopidogrel treatment as part of a 30-day clinical outcome trial in the Russian and Buryat regions of East Siberia. Methods: The study included 118 Russian (from Irkutsk) and 109 Buryat (from Ulan-Ude) patients with emergency admission for percutaneous coronary interventional treatment of acute coronary syndrome (ACS). The patients were stratified by the presence of the CYP2C19*2, CYP2C19*3, CYP2C19*17 alleles, and the VEGFR-2 rs2305948 allele. Safety and efficacy endpoints were analyzed 30 days following coronary stenting (CS). Results: There was no significant difference found in the Russian and Buryat patients in terms of the frequency of the CYP2C19*2 minor allele (10.2% in the Russian against 12.8% in the Buryat patients, odds ratio [OR] = 1.167, confidence interval [CI] 0.729-2.323). However, the frequency of the CYP2C19*3 allele was significantly higher in the Buryat patients than in the Russian patients (12.8% vs. 2.1%), OR = 5.600, CI 2.579-17.974; while in the Russian patients the frequency of the CYP2C19*17 allele was higher than the Buryat patients (23.3% in Russian patients vs. 10.1% in Buryat, OR = 2.500, CI 1.587-4.618). No significant differences were found in the prevalence of the VEGFR-2 rs2305948 alleles between the two groups of patient populations (12.5 in Buryat patients vs. 11.5% in Russian, OR = 1.040, CI 0.614-1.980). The Buryat patients were highly significantly more likely to experience adverse effects associated with the inefficacy of clopidogrel treatment, that is, early recurrent ischemic pains after CS, than the Russian patients (χ2 = 11.325, p < 0.001). Conclusion: The Buryat patients receiving clopidogrel treatment after CS have a reduced risk of small or large hemorrhages, and an increased risk of thrombotic complications compared with Caucasians. These results suggest that other antiplatelet drugs should be used for treating the Buryat patients with ACS.

CYP2C19 polymorphism frequency in Russian patients in Central Russia and Siberia with acute coronary syndrome.

PURPOSE: The aim of this study is to investigate the frequency of CYP2C19*2, *3 allelic variants, associated with poor response to clopidogrel, and CYP2C19*17, associated with excessive response to clopidogrel, in patients with acute coronary syndrome (ACS) from Siberia and Moscow regions of Russia. PATIENTS AND METHODS: The study included 512 ACS patients who were subsequently treated with coronary arterial stenting. The subjects assigned were from the cities of Central (Novosibirsk, Kemerovo), Eastern (Irkutsk), Northern (Surgut) Siberia regions and from Moscow region. The mean age of patients enrolled was 63.9±10.9 years. Among the assigned subjects, the proportion of men accounted for 80% and women 20%. RESULTS: According to the results obtained in the present study, from 16% up to 27.5% of patients in different regions of Russia have at least one CYP2C19 "poor metabolizer" (PM) allele variant affecting clopidogrel metabolism and, therefore, suppressing its antiplatelet activity. CYP2C19*17 allele variant was identified with the frequency of 15.4% up to 33.3%. The study revealed the presence of statistically significant differences in CYP2C19*3 allele frequency between the Russian ethnic group patients from Eastern and Central Siberia (p=0.001; odds ratio=1.05 [95% confidence interval 1.01-1.09]). CONCLUSION: The study revealed statistically significant differences between the allele frequencies in Eastern and Central Siberia, which can probably be caused by a considerable number of Buryats inhabiting Eastern Siberia.

The level of free circulating mitochondrial DNA in blood as predictor of death in case of acute coronary syndrome.

BACKGROUND: The efficacy of treating acute myocardial ischemic damages depends, to a large extent, on the development of technologies for predicting their course and outcome. The aim of this paper was to explore whether it would be possible to consider the content of free circulating mitochondrial DNA as a danger-associated molecular pattern for assessing the probability of death from myocardial infarction. METHODS: We have analyzed the clinical outcomes based on discharge summaries and autopsy reports obtained in the course of the PROTOCOL observational trial. This study was approved by the Irkutsk Scientific Center of Surgery and Traumatology ethics committee (protocol No. 3, 10.08.2015). To examine whether the assessment of the level of free circulating mtDNA in acute coronary syndrome can help predicting clinical outcomes, all patients were divided into two groups: group 1, involving those who survived during 30 days after hospitalization, and group 2, involving those who died during this time. A quantitative analysis of the free circulating mtDNA was conducted using the PCR method in situ. RESULTS: The analysis showed that in patients who survived the level of freely circulating mtDNA (36.0 copies/ml) was 164 times lower than in those who died (5900 copies/ml, p = 0.049). It should be mentioned that according to the logistic regression analysis, the probability of death of patients with the increased level of blood plasma mtDNA (more than 4000 copies/ml) is 50%. CONCLUSIONS: Thus, the PROTOCOL observational trial proved that the increase in the content of free circulating mtDNA in blood is a predictor of lethal outcome in patients with acute coronary syndrome. Trial registration The observational studies (those in which the assignment of the medical intervention is not at the discretion of the investigator) do not require registration.