Myectomy versus alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy

OBJECTIVES: There is very little evidence comparing the safety and efficacy of alcohol septal ablation versus septal myectomy for a septal reduction in patients with hypertrophic obstructive cardiomyopathy. This study aimed to compare the immediate and long-term outcomes of these procedures. METHODS: Following propensity score matching, we retrospectively analysed outcomes in 105 patients who underwent myectomy and 105 who underwent septal ablation between 2011 and 2017 at 2 reference centres. RESULTS: The mean age was 51.9 ± 14.3 and 52.2 ± 14.3 years in the myectomy and ablation groups, respectively (P = 0.855), and postoperative left ventricular outflow tract gradients were 13 (10-19) mmHg vs 16 (12-26) mmHg; P = 0.025. The 1-year prevalence of the New York Heart Association class III-IV was higher in the ablation group (none vs 6.4%; P = 0.041). The 5-year overall survival rate [96.8% (86.3-99.3) after myectomy and 93.5% (85.9-97.1) after ablation; P = 0.103] and cumulative incidence of sudden cardiac death [0% and 1.9% (0.5-7.5), respectively P = 0.797] did not differ between the groups. The cumulative reoperation rate within 5 years was lower after myectomy than after ablation [2.0% (0.5-7.6) vs 14.6% (8.6-24.1); P = 0.003]. Ablation was associated with a higher reoperation risk (subdistributional hazard ratio = 5.9; 95% confidence interval 1.3-26.3, P = 0.020). At follow-up, left ventricular outflow tract gradient [16 (11-20) vs 23 (15-59) mmHg; P < 0.001] and prevalence of 2+ mitral regurgitation (1.1% vs 10.6%; P = 0.016) were lower after myectomy than after ablation. CONCLUSIONS: Both procedures improved functional capacity; however, myectomy better-resolved classes III-IV of heart failure. Septal ablation was associated with higher reoperation rates. Myectomy demonstrated benefits in gradient relief and mitral regurgitation elimination. The results suggest that decreasing rates of myectomy procedures need to be investigated and reconsidered. © The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved

Tunka Advanced Instrument for cosmic rays and Gamma Astronomy

The paper is a script of a lecture given at the ISAPP-Baikal summer school in 2018. The lecture gives an overview of the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA) facility including historical introduction, description of existing and future setups, and outreach and open data activities.Comment: Lectures given at the ISAPP-Baikal Summer School 2018: Exploring the Universe through multiple messengers, 12-21 July 2018, Bol'shie Koty, Russi

Meshalkin National Medical Research Center

We present three cases of successful transatrial transcatheter valve-in-valve implantation in patients with bioprosthetic mitral valve dysfunction. Patients with a high surgical risk, with severe heart failure due to bioprosthetic mitral valve dysfunction, were implanted with transcatheter prostheses using the transatrial approach.Transesophageal echocardiography and fluoroscopy-guided transcatheter mitral prosthetic valve positioning was performed. With a cardiac pacing at 180 bpm, a transcatheter valve was implanted. The transcatheter valves functioned properly after surgery. The patients were discharged in satisfactory condition

TAIGA -- an advanced hybrid detector complex for astroparticle physics and high energy gamma-ray astronomy

The physical motivations, present status, main results in study of cosmic rays and in the field of gamma-ray astronomy as well future plans of the TAIGA-1 (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based gamma-ray astronomy and astroparticle physics at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. The pilot TAIGA-1 complex is located in the Tunka valley, ~50 km west from the southern tip of the lake Baikal.Comment: Submission to SciPost Phys. Proc., 10 pages, 2 figure

Primary Cosmic Rays Energy Spectrum and Mean Mass Composition by the Data of the TAIGA Astrophysical Complex

The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 year. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ - $2\cdot 10^{16}$\,eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m.}Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Pro

КАРКАСНЫЕ БИОПРОТЕЗЫ В АОРТАЛЬНОЙ ПОЗИЦИИ: АНАЛИЗ НЕПОСРЕДСТВЕННЫХ РЕЗУЛЬТАТОВ НА ОСНОВЕ РЕТРОСПЕКТИВНОГО ИССЛЕДОВАНИЯ

Purpose. Retrospective analysis of the immediate results of the treatment of these patients will form an idea of the need for a prospective randomized study.Materials and methods. Are analyzed the results of 411 operations performed in patients with aortic stenosis. The first group – 227 patients with implanted bioprosthesis in the aortic position UniLine, the second group – 184 patients with implanted stented bioprosthesis Biolab.Results. Postoperative mortality in group I was 1.8 % (4 patients), in group II – 2.7 % (5 patients) (p=0.8). To determine the factorsthat have a connection to the pressure gradient in the aortic prosthesis, regression analysis was performed. In group I, the relationship between the peak pressure gradient and body mass index (p = 0.001). In group II, the relationship peak pressure gradient and stroke volume of the left ventricle, body mass index and diameter of the prosthesis. In group I in the perioperative period required reimplantation valve 1 (0.4 %) patient. Reason dysfunction – iatrogenic damage to the prosthesis. In group II all recorded 3 (1.6 %) early prosthetic dysfunction, including 1 (0.5 %) – iatrogenic and 2 (1 %) – due to the prosthesis itself.Conclusion. A prospective randomized controlled study conducted over a long period of time, a few clinics at the same time, allow more objectively assess the advantages and disadvantages of dentures and to define prospects of development of this direction in Russia.Цель. Ретроспективный анализ непосредственных результатов лечения данной категории пациентов позволит сформировать представление о необходимости проведения проспективного рандомизированного исследования.Материалы и методы. Анализу подвергнуты результаты 411 операций, выполненных больным с аортальным стенозом. I группа – 227 больных с имплантированным в аортальную позицию биопротезом «ЮниЛайн», II группа – 184 пациента с имплантированным каркасным биопротезом «БиоЛАБ».Результаты. Послеоперационная летальность в I группе составила 1,8 % (4 пациента), во II группе – 2,7 % (5 пациентов) (р=0,8). Для определения факторов, имеющих связь с градиентом давления на аортальном протезе, был проведен регрессионный анализ. В I группе выявлена взаимосвязь между пиковым транспротезным градиентом давления (ПТГД ) и индексом массы тела (р=0,001). Во II группе выявлена взаимосвязь между ПТГД и ударным объемом левого желудочка, индексом массы тела, диаметром протеза. В I группе в периоперационном периоде потребовал реимплантации клапана 1 (0,4 %) пациент. Причина дисфункции – ятрогенное повреждение протеза. Во II группе всего зафиксировано 3 (1,6 %) ранних дисфункции протеза, из них 1 (0,5 %) – ятрогенная и 2 (1 %) – обусловленные непосредственно протезом.Выводы. Проспективное рандомизированное контролируемое исследование, проведенное в продолжительном периоде в нескольких клиниках одновременно, позволит более объективно оценить преимущества и недостатки протезов и определить перспективы развития этого направления в России

Temperature effect corrections for URAGAN based on CAO, GDAS, NOAA data

For the analysis of muon flux variations caused by extra-atmospheric processes it is necessary to introduce corrections for meteorological effects. For temperature effect (TE) correction it is necessary to know the temperature profile of the atmosphere. As a rule, this profile is measured by meteorological balloons two or four times a day. Alternative sources are satellite observations and data obtained from models of atmosphere used for weather forecasting. Vertical temperature profiles obtained from NOAA satellites, GDAS (Global Data Assimilation System) and CAO data (Central Aerological Observatory, Russia) for standard isobaric levels were compared. Mean value of temperature difference for most levels does not exceed 1 K. Comparison of URAGAN data corrected for TE with CAO information, satellites and GDAS shows a good agreement. Counting rate and anisotropy of the muon flux corrected for meteorological effects for 2007-2014 are presented

The precision of the IACT mechanical mounts of the TAIGA observatory

The TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) observatory is located in the Tunka valley (~50 km west from the southern shore of Lake Baikal) at an altitude of 675m a.s.l. The TAIGA observatory aims to address gamma-ray astronomy at energies from a few TeV to several PeV and CR physics from 100 TeV to several EeV. Its main feature is the complementary, hybrid approach to distinguish CR events from those of gamma rays. Currently TAIGA consists of ~80 wide-angle air Cherenkov detectors (HiSCORE stations), three ~4m diameter IACTs and several hundred surface and underground muon detectors, grouped in three jointly operating arrays. The exceptional feature of the TAIGA IACT array is it’s topology that allows one to aim for the optimal cost/performance by scanning the optimal inter-telescope distances from 300m up to 600m. The IACTs have alt-azimuth type mounts and 576-pixel imaging cameras in the foci, covering 9.6° aperture in the sky. The segmented reflectors of ~10m² area follow the Davis-Cotton design. The largest diameter of the hexagonal shape reflector is 4.3m and the focal length is 4.75m. The rigid telescope mount provides a maximum displacement of EAS image below 2mm (i.e. ≤ 0.024°) in the photodetector plane. The main parameters of IACTs are of a crucial importance for their efficient operation and is presented

Method of Separation Between Light and Heavy Groups of Primary CR Nuclei by LDF of Cherenkov Light in the Range 300–3000 TeV

The problem of chemical composition below the knee in the cosmic-ray energy spectrum has not yet been solved due to low statistics collected from direct experiments. In the HiSCORE experiment the lateral distribution functions (LDF) of Cherenkov light of EASs with energy greater than hundreds of TeV can be measured in detail for millions of individual events. A full steepness of LDF is sensitive to the depth of shower maximum and as a result to primary particle type. In this paper, we developed a parametric method of separation between heavy and light groups of nuclei using the ’knee-like’ approximation of LDF and taking into account measurement uncertainty