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This review summarizes the available information on the epidemiology and prognosis of patients with left bundle branch block (LBBB), morphological alterations of the myocardium both resulting in and ensuing LBBB, cardiac biomechanics in LBBB, and possibilities of its correction.

We present two cases of successful pharmacological cardioversion using antiarrhythmic drug refralon in patients with persistent atrial fibrillation after pulmonary vein cryoablation and ineffective electrical cardioversion. These clinical cases represent the first experience of successful use of refralon in patients who underwent cryoablation.

An integral computer model/program AusEvol Pro was developed to describe the evolution of steel microstructure during thermomechanical processing (hot rolling, forging), as well as subsequent heat treatment (normalization, tempering), and to evaluate the final mechanical properties (yield stress, tensile stress, elongation), hardness and impact toughness. The program implements a set of physically based models that allow quantitative description of all significant processes of steel structure formation with account of the effects of chemical composition both during thermomechanical processing and heat treatment. Calculations of the final mechanical properties are carried out using the developed models that take into account all physically meaningful contributions. The models created are verified both on the extensive database of our own experimental studies and on reliable data from literature for steels of various chemical compositions.

Introduction Atrial fibrillation (AF) is one of the most common forms of arrhythmia. Niferidil is a new russian class III antiarrhythmic drug that has shown high efficiency in restoration of sinus rhythm (SR) in persistent AF (87%) in clinical trials that is non-inferior to direct current cardioversion. Currently, a three-stage scheme of drug administration is used (10 μg/kg – 10 μg/kg – 10 μg/kg). In a number of patients, SR restored before the end of injection of the first dose of the drug, which suggests the effectiveness of an even lower dose (5 μg/kg) of the drug, which has not been studied in clinical trials. Objective To evaluate the effectiveness and safety of the modified protocol of niferidil administration in patients with paroxysmal and persistent AF. Materials and methods This study included 100 patients with paroxysmal (n=20) and persistent AF (n=80), 53 of them were men, mean age 63±12 years. After exclusion of contraindications, all patients received niferidil according to the following scheme. The initial dose of niferidil was 5 μg/kg of body weight, if AF did not terminate after 15 minutes (min.), niferidil was additionally administered at a dose of 5 μg/kg (total dose of 10 μg/kg). If SR was not restored patients received subsequent injections of niferidil 10 μg/kg, each after 15 min. (maximal total dose of 30 μg/kg). Injections were discontinued in case of SR restoration, QTc >500 ms or proarrhythmia. All patients underwent continuous ECG monitoring within 24 hours to assess effectiveness and safety of niferidil. Results SR was restored in 94 out of 100 patients (cumulative effectiveness of niferidil in doses up to 30 μg/kg was 94%). 37% of patients restored SR after a dose of 5 μg/kg. All 20 patients with paroxysmal AF restored SR within 24 hours. Niferidil restored SR in 74 of 80 patients with persistent AF (92,5%). 26 (32,5%) of them restored SR after administration of 5 μg/kg dose, 62% – after 10 μg/kg dose and 92,5% – after 30 μg/kg dose. In none of the cases was there any development of life-threatening ventricular arrhythmias. Prolongation of the QTc >500 ms was recorded in 16 patients (16%). In all patients, prolongation of the QTc interval to the maximum values was noted within the first 6 hours from the start of drug administration. Bradyarrhythmias after SR recovery were reported in 11 patients (11%). In all cases sinus bradycardia was asymptomatic and resolved within a few minutes without any therapeutic intervention. Conclusions The modified protocol of cardioversion allows SR to be restored in a significant number of AF patients lower doses of niferidil. The drug is highly effective in the treatment of paroxysmal AF, while in many patients, SR recovery occurs after injection of lowest (5 μg/kg and 10 μg/kg) doses of the drug. Despite the prolongation of the QTc interval >500 ms in a number of patients, in none of the cases the development of Torsades de pointes observed. Funding Acknowledgement Type of funding sources: None.

This article analyzes the known techniques of calculating the energy intensity of continuous hot rolling of broad steel strips. The analysis is used to propose new rolling modes to ensure better energy efficiency by considering the influence of the partial cold work of the strip’s material on the energy consumption. The proposed modes were tested and adopted in the continuous finishing train of rolling mill 2000.

The study results show the normal growth of recrystallized ferrite grains under the isothermal annealing of cold-rolled sheets made of five automotive steels (DX54D, HX260YD, CR210B2, 08ps, HX300LAD) obtained using a Gleeble 3800 experimental system. Based on the obtained data, a mathematical model of this process has been developed. The simulation results obtained for the kinetics of ferrite grain growth in a practically important annealing temperature range agree well with the experimental data.

Aim To identify risk factors for recurrence of atrial fibrillation (AF) following cryoballoon ablation (CBA).Material and methods This prospective study included patients with paroxysmal AF who had undergone CBA (141 patients, median age 60 years, 3% men). The evaluation prior to CBA included clinical instrumental parameters (electrocardiography (ECG), 24-h ECG monitoring, echocardiography, contrast-enhanced cardiac multispiral computed tomography). Also, possible intraoperative indexes that could affect the CBA effectivity, were evaluated. The postoperative follow-up duration was 12 months. Effectivity was assessed during in-person visits at 3, 6, and 12 months, when questioning of patients and 24-h ECG monitoring were performed. CBA was considered ineffective if the patient had recurrences of any atrial tachyarrhythmia longer than 30 sec after the end of the 3-month “blind” period.Results During the 12-month follow-up, recurrences of atrial tachyarrhythmia were observed in 46 (32.6 %) patients. Patients with ineffective CBA more frequently had AF during the first 3 months (71.7 % vs. 11.6 %; рvs. 20.0 %; р=0.008), and stroke/recurrent ischemic attacks (15.2 % vs. 5.2 %; р=0.047). Multifactorial regression analysis showed that the factors of AF recurrence included common PV collector (relative risk (RR) 2.35; 95 % confidence interval (CI) 1.29–4.25; р=0.005), multiple ineffective AADs (RR 1.42; 95 % CI 1.08–1.86; р=0.011), and early AF recurrence (RR 7.57; 95 % CI 3.84–14.90; рConclusion Common PV collector and multiple ineffective AADs are risk factors of ineffective CBA. Early recurrences during the first 3 postoperative months are a significant risk factor of long-term AF recurrences.

Alterations of heart rhythm are a common clinical event. They can be caused by almost any kind of heart disorder. Atrial fibrillation (AF) is the most common type of abnormal heart rhythm. Prevalence of AF in the general population is 1-2%, and given that AF incidence rate continues to increase it can be predicted that the number of patients will be doubled within the next 50 years. This review provides the most recent diagnostic and treatment methods, including both unique domestic antiarrhythmic drugs and non - drug methods for AF treatment which were developed and implemented in clinical practice at NMRC of Cardiology of the Ministry of Health of the Russian Federation.Нарушения ритма сердца - широко распространенное клиническое явление. Их возникновение может быть обусловлено практически любым видом сердечной патологии. Фибрилляция предсердий (ФП) является наиболее распространенной формой нарушений ритма сердца. Распространенность ФП в общей популяции составляет 1-2%, и продолжающийся рост заболеваемости позволяет прогнозировать удвоение количества больных в течение ближайших 50 лет. В данном обзоре представлены новейшие диагностические методики и методы лечения, включающие как уникальные отечественные антиаритмические препараты, так и немедикаментозные методы лечения ФП, разработанные и внедренные в клиническую практику в НМИЦ кардиологии Минздрава России.

Kinetic recrystallization curves are obtained during isothermal annealing of cold-rolled automobile body sheet steels of five grades. The most correct technique of processing EBSD maps is chosen by comparing the degrees of recrystallization estimated by various techniques of processing EBSD maps with the softening determined by hardness measurements.

Based on the results of an experimental investigation of cold-rolled automobile body sheet steels of various strength classes, we developed a mathematical model to predict the recrystallized ferrite grain size as a function of the ferrite grain size after hot rolling and the strain during cold rolling. The model can reproduce the experimental data at a good accuracy.

A model is proposed for predicting the Lankford coefficient of steel sheet produced for the auto industry at PAO Severstal. The set of empirical model parameters is determined using an experimental database on the mean Lankford coefficient (for 138 strips of 13 steels differing greatly in composition) and additional databases on calculated steel microstructure parameters after hot rolling, and after heat treatment of cold-rolled strips. The mean error in calculations of the Lankford coefficient using the model is 7.1%. It is found that the Lankford coefficient is determined not only by the carbon content in the solid solution before cold rolling but also by the amount of carbon deposited at the ferrite grain boundaries in the form of tertiary cementite. The additional free carbon appearing in the solution when the tertiary cementite particles dissolve on heating of the cold-rolled sheet significantly affects the recrystallization and the texture formation.

The softening kinetics associated with recovery and recrystallization is investigated, along with the kinetics of phase transformation (austenitization) on heating cold-rolled autompotive steel sheet. The kinetics of softening in isothermal holding is studied using the Gleeble 3800 system for 12 steels, and the phase transformation in continuous heating at constantrate is studied for 6 steels of different strength class, with different chemical composition. Considerable slowing of the steel’s recovery and recrystallization is observed with increase in the Mn and Ti content in the ferrite solid solution. The grain size of the recrystallized ferrite hardly depends on the annealing temperature. The results may be used in developing a quantitative integral model to describe the complex microstructural evolution of cold-rolled steel sheet on annealing in industrial production.

An integral computer model STAN 2000 designed for of-line simulation and control of hot rolling on mill 2000 of SEVERSTAL was developed. The capabilities of the model include the following features: ‒ calculations of power parameters for all stands of mill 2000 for a given rolling schedule; ‒ strip temperature calculations depending on selected rolling and accelerated cooling regimes; ‒ follow-up of steel microstructure evolution at all stages of strip production and prediction of ultimate mechanical properties (yield stress, ultimate tensile stress, relative elongation and toughness); ‒ optimization of rolling regimes for existing steel grades and developing them for a new one. The STAN 2000 program is written in С++ programming language and can work on all modern Microsoft Windows family operating systems. The program has a well-designed and user-friendly interface facilitating its practical use. The integral model was calibrated using an extensive data base on rolling regimes and forces, measured temperatures and final mechanical properties for a number of steel grades rolled on mill 2000 of SEVERSTAL with chemical compositions covering the following range of alloying elements content (mass.%): С(≤0.65); Mn(≤2.0); Si(≤1.0); Cr(≤0.9); Ni(≤0.6); Cu(≤0.5); Mo(≤0.4); Nb(≤0.05); V(≤0.065); Ti(≤0.06); B(≤0.003). The examples of STAN 2000 program use in practice of industrial hot strip production on mill 2000 of SEVERSTAL are presented and discussed.

An integral computer model/program STAN 2000 for simulation of steels hot rolling on mill 2000 of SEVERSTAL was developed. The capacity of the model includes, for example, the following features:‒ control of power parameters and prediction of hot strip temperature for a given rolling and accelerated cooling regimes;‒ follow-up of the evolution of steel microstructure at all stages of strip production and prediction of ultimate mechanical properties (yield stress, ultimate tensile stress and relative elongation);‒ optimization of rolling regimes for existing steel grades and developing them for a new ones.The STAN 2000 program is written in С++ programming language and can work on all modern Microsoft Windows family operating systems. The program has a well-designed and user-friendly interface facilitating its practical use.The integral model was calibrated using an extensive data base on rolling regimes and forces, measured temperatures and final mechanical properties for a number of steel grades rolled on mill 2000 of SEVERSTAL with chemical compositions covering the following ranges of alloying elements content (mass.%): С(≤0.65); Mn(≤2.0); Si(≤1.0); Cr(≤0.9); Ni(≤0.6); Cu(≤0.5); Mo(≤0.4); Nb(≤0.05); V(≤0.065); Ti(≤0.06); B(≤0.003).Some results of calculations performed with STAN 2000 program for temperatures, rolling forces and mechanical properties are presented and compared with experimental data. Some examples of the program utilization in hot strip production on mill 2000 of SEVERSTAL are presented and discussed.

We present in this article 2 cases of successful pharmacological restoration of sinus rhythm by a new class III antiarrhythmic drug refralon in patients with obesity and persistent atrial fibrillation. In both cases, the effective use of refralon was preceded by repeated ineffective attempts of electrical cardioversion. In the article we discuss the role of obesity as the factor leading to a substantial increase of transthoracic electrical resistance, and thus significantly reducing the probability of sinus rhythm restoration by means of electrical cardioversion. The clinical examples described in this article clearly show that the use of refralon may represent a unique clinical alternative to electrical cardioversion for sinus rhythm restoration in patients with persistent atrial fibrillation, and in some cases where the success of electrical cardioversion is obviously questionable, like in patients with severe obesity, the use of refralon seems preferable.

OBJECTIVE To assess and compare the safety and efficacy of allapinine and quinidine bisulphate in the treatment of patients with persistent atrial fibrillation after cardioversion. Design--Prospective, randomised, open study. Patients--73 consecutive patients (men only, mean age 44 ± 11 years) with persisnent atrial fibrillation and flutter. Interventions--37 patients were randomised to allapinine (ALP) (1.5 mg/kg/d), 36 to quinidine bisulphate (QUIN) (15 mg/kg/d) with subsequent successful pharmacological or electrical cardioversion. Main outcome measures--Recurrence of atrial fibrillation or side effects. RESULTS In the ALP group 15 of the 37 patients developed atrial fibrillation up to 12 month of follow-up, while in the QUIN group 20 patients developed atrial fibrillation and 5 experienced significant side effects. Relative risk (RR) (ALP vs QUIN) 0.58 (95% CI 0.37-0.91, p < 0.02). The number needed to treat (NNT) was (-3.48) (14.2-1.97 harm). When 5 patients with significant side effects were excluded from the analysis RR was 0.62 (95% CI 0.39-1.0, p = 0.052) and NNT--(-4.1) (122.7-2.1 harm) but power of the study was too low--67%. CONCLUSION Allapinine is as effective as quinidine bisulphate in the long term treatment of patients with persistent atrial fibrillation after successful cardioversion but causes significantly less side effects.

An integral mathematical physically based model is developed for prediction of the microstructure and mechanical properties of steels processed in accordance with a given hot deformation and accelerated cooling regimes. The model predicts austenite microstructure evolution under hot deformation, as well as its transformation during subsequent cooling with account of formation of ferrite, pearlite, bainite and martensite. Structure-property relationships are developed using an extensive experimental database chemical composition - microstructure - mechanical properties obtained for 10 steel grades. Austenite transformation depending on grain size, cooling rate and preliminary plastic deformation was investigated with the help of Gleeble 3800 system to obtain a set of practically important morphologically different microstructures for each steel grade. A quantitative analysis of the microstructures was performed using optical and scanning electron microscopy (EBSD-method). Investigation of the mechanical properties of steels with wide spectrum of obtained microstructures was carried out on the double-samples processed using Gleeble 3800. The predicted microstructure parameters for investigated steels obtained using the developed model, as well as their mechanical properties, are in good agreement with the experimental data.

A mathematical physically based model of the decomposition of undercooled austenite (γ-phase) with the formation of ferrite (α-phase) and pearlite has been developed. The model differs from the currently existing analogs by a new approach to the inclusion of the effect of complex alloying of steels on the nucleation rate of ferrite grains and on the mobility of the α/γ-phase boundary. In the model, the effect of alloying of steels with substitutional elements on the diffusion coefficient of carbon in the bulk of austenite is taken into account. The results of the modeling of the kinetics of austenite decomposition and the calculation of the final ferrite grain size are in good quantitative agreement with the experimental data obtained for a set of steels with a wide range of chemical compositions.

Mathematical models are proposed for calculating the onset temperature of ferrite transformation and the ferrite grain size as a function of the cooling conditions and the initial austenite grain size. The models are calibrated on the basis of experimental data for steels with ferrite-pearlite microstructure. The models are integrated in HSMM software, with considerable gain in computational power when considering the mechanical properties of steel rolled on the 2000 mill at OAO Severstal’.

An experimental study (physical modeling) of the processes of austenite microstructure evolution occurring under hot rolling was performed for line-pipe steels with different chemical composition. All investigations were conducted with the help of the Gleeble 3800 system. Empirical quantitative models of austenite grain growth, static and dynamic recrystallization, as well as a flow stress model were developed. The effect of complex alloying by such elements as C; Mn; Si; Ni; Mo; Nb; Ti; and V on grain growth and recrystallization is accounted for under the condition that all elements are in a solid solution. The set of the models empirical parameters is determined utilizing corresponding experimental data available from literature. Modeling results for static recrystallization and flow stress in the investigated steels are compared with experimental data.

Results of modification of the HSMM model (Hot Strip Mill Model) for enhancing precision of the mechanical properties prediction for hot-rolled steels after rolling on the mill 2000 of OAO Severstal are presented.

The experimental data on the self-diffusion coefficient of austenite with different chemical compositions obtained by the radioactive isotope method have been analyzed quantitatively. The self-diffusion activation energy in pure γ-iron is shown to be ∼312 kJ/mol. Alloying of austenite with such elements as Mn, Mo, Nb, Ti, and Si (to a lower degree) increases the self-diffusion activation energy, and alloying with C, V, or Cr (for the element content ≥3 at %) decreases it. The empirical formula is derived for calculation of the self-diffusion activation energy in austenite solid solutions with complex composition.

The influence of deformation-induced ferrite transformation on the microstructure of microalloyed pipe steel is investigated by means of a Gleeble 3800 test system. The results show that such dynamic transformation permits considerable reduction in ferrite grain size and improves the mechanical properties of the steel.

We aimed to compare safety and effectiveness of new class III antiarrhythmic drug Refralon with direct current cardioversion (DCC) in patients with persistent atrial fibrillation (AFib). 60 patients with persistent AFib were randomized to groups of DCC (n=30) and pharmacological conversion (PCV; n=

The effect of the thermomechanical treatment parameters on the structure and properties of a high-strength nitrogen-bearing austenitic Cr-Ni-Mn steel is studied using a Gleeble 3800 plastometer. An increase in the interdeformation pause time during multipass deformation of the steel is shown to decrease the temperature of formation of carbonitride hardening phases in its structure. A shift in the temperature range of deformation toward low temperatures is found to increase the strength properties of the steel, and its plasticity decreases.

This article reviews experimental and clinical studies of a novel antiarrhythmic agent niferidile. Niferidile, a class III antiarrhythmic agent, blocks potassium outward currents, prolongs repolarization and refractory periods predominantly in atria than in ventricles. Intravenous Niferidile was efficient for interruption of AV-nodal and orthodromic re-entrant tachycardias with rates of 75% to 80%. Niferidile had a conversion rate of up to 87.3% in persistent atrial fibrillation and up to 100% in persistent atrial flutter. Proarrhythmic action of niferidil administration manifested as nonsustained torsade de pointes and monomorphic ventricular tachycardia in 1.2 and 3.7% of cases, respectively. Niferidile can be used for pharmacological cardioversion of persistent atrial fibrillation and flutter as an alternative to electrical cardioversion.

Aims To study the efficacy and safety of the new class III antiarrhythmic agent niferidil for pharmacological cardioversion in patients with persistent atrial fibrillation (AF) and atrial flutter (AFl). Methods and results One hundred thirty-four adults (aged 57.8 ± 11 years, 90 males) were included with median AF duration of 3 (1.5-6) months. All patients received a total of 10-30 μg/kg, niferidil, intravenously, in 1-3 (if needed) consecutive boluses at 15-minute intervals. Holter electrocardiogram monitoring was started before infusion and was continued for 24 hours. The criterion for an antiarrhythmic effect was sinus rhythm restoration within 24 hours of the initial bolus. Niferidil converted AF to sinus rhythm in 47.7% of cases after bolus 1, in 62% of cases after bolus 2, and in 84.6% of cases bolus 3. Niferidil induced a 100% recovery rate in patients with AFl and a 91.8% recovery rate in patients with AF of duration from 8 days to 3 months. Nonsustained torsade de pointes occurred in 1 patient (0.7%), and nonsustained monomorphic ventricular tachycardia was observed in 5 patients (3.7%). Conclusions The new intravenous class III drug niferidil demonstrated high conversion rates of 84.6% in patients with persistent AF and 100% in patients with persistent AFl. Niferidil may be used as a possible alternative to electrical cardioversion for pharmacological cardioversion of persistent AF/AFl.

In our study we compared effect of cardiac resynchronization therapy (CRT) in chronic heart failure (CHF) patients with permanent atrial fibrillation (AF) and patients with sinus rhythm. Special feature of our work was that patients with permanent atrial fibrillation didnt have obligatory ablation of atrio-ventricular node but underwent aggressive rate control to achieve more than 90% of biventricular (BV) complexes. We used 24 hours Holter monitoring because there are data that this method is more accurate than CRT counters.We included 30 patients: 21 patients with sinus rhythm and 9 patients with permanent AF with ejection fraction35%, II-IV NYHA class and wide QRS (120 ms). We examined patients before implantation of CRT and after 6 months.mean NYHA class decreased from III to II. Distance at 6-min walk test increased by 107 m in AF group and by 105 in sinus rhythm group. EF increased by 7% in AF group and by 6% in sinus rhythm group. Mean time of further observation was 2 years (from 10 months to 5 years). There was 1 death (11.1%) in AF group and 3 deaths (15%) in sinus rhythm group (p0,05).CRT is effective in CHF patients with permanent AF and pharmacological rate control if percent of BV pacing is more than 90% on Holter monitoring.

Ferrite recrystallization in cold-rolled sheets of automotive steels has been studied using a Geeble 3800 complex. Mathematical models for quantitative description of the process kinetics and prediction of the recrystallized ferrite grain size have been developed. These models enable performing calculations for any arbitrary heating regimes, including those that are used in industrial production practice, and allow taking into account the effects of a fairly wide range variation of the chemical composition of steels.