Review concerns the novel scientific approach studying the importance of micro-RNAs (miRs) as the putative novel markers and therapeutic targets in cardiovascular pathology. MiRs were first described in nematode worm
only in 1993. Then in a very short period of time their presence was documented in variety of plants, animals, viruses. Up to date over 700 miRs have been registered in humans in the central database of the Wellcome Trust Sanger Institute. MicroRNAs are short, 19-24-nucleotide-long non-coding RNAs involved in the control of gene expression, which as it seems can play an important role in developmental biology and regulation of many
physiological and pathological processes in the adult organisms, including cardiovascular system. The article contains information about biogenesis of miRs, supposed mechanism of action, cardiac-expressed molecules
(miR-1, -133, -206, -208), as well as miRs, which probably play a significant role in maintaining endothelial homeostasis (miR-143/145, -126, -92 cluster). According to the latter data, miRNAs have been implicated in
myocardial hypertrophy, fibrosis, and vascular disease. The detection and quantification of circulating microRNAs may represent a novel noninvasive tool to detect and monitor disease activity. Recently, miRNAs have received much attention regarding their suitability as biomarkers for disease, for example, myocardial infarction.
Contemporary data about clinical application of the speckle tracking echocardiography are presented. The physical basis, terminology, reference values and limitations of the method are described. The analysis of the reproducibility of speckle tracking parameters was performed. The diagnostic accuracy of the method in some cardiac diseases, like arterial hypertension, coronary heart disease, cardiomyopathies and heart failure was shown. The clinical cases of cardiac diseases in which speckle tracking echocardiography was used are presented.
Currently there is no doubt that elevated heart rate (HR) at rest is an indicator of poor prognosis in patients with IHD and heart failure, but the range of safe level of HR for these patients has yet to be established. It is suggested that the level of HR reduction in these patients should be the primary criteria of drugs dosage that affects HR (Β-blockers, angiotensin-converting enzyme inhibitors, If-channels). Also, it has been determined that the appropriate lower boundary of HR reduction correlates with severity of hemodynamic disorders. Based on recent data from meta-analysis studies using beta-blockers and SHIFT study, it is suggested that the upper HR boundary should be in the range of 80–85 bpm and the lower boundary should be in the range of 65–70 bpm for patients with moderate to severe systolic HF.
According to the contemporary views, pathogenesis of atherosclerosis has complex nature with involvement of both lipid and non-lipid factors in development and progression of the process and determination of its clinical course. Nevertheless so far, especially in clinical practice, the unitary – cholesterol hypothesis of atherosclerosis did not loose its value. Diagnosis, primary and secondary prevention, pharmacotherapy of atherosclerosis are based on interventions which promote the lowering of blood cholesterol. However, currently the most prevalent type of atherogenesis combined with obesity, metabolic syndrome, insulin-independent diabetes mellitus develops in absence of hypercholesterolemia. Therefore, problems of diagnosis and treatment of such patients are still unresolved. In the work based on the results of contemporary research and original investigations we analyzed the pathogenetic significance and value of main atherogenic factors. It was shown that severe coronary atherosclerosis leading to myocardial infarction may appear on the background of normal values of total cholesterol and low density lipoprotein cholesterol. Proatherogenic dyslipidemia, systemic inflammation, atherogenic and immunogenic lipoprotein modification were marked at background of normal and even low levels of cholesterol. Though hypercholesterolemia is a significant and undisputable marker of atherosclerosis, its absence does not afford to exclude the presence of atherosclerosis. Thus the results of the investigation confirm the insufficient value of total blood cholesterol as index of atherosclerosis, intensity of its progression and necessity of more deep analysis of atherogenic factors for the evaluation of the risk of ischemic heart disease and effectiveness of the treatment