Modern weapons cause severe damage, accompanied by high rates of complications and mortality. The investigation of such kinds of weapons is in high demand considering the ongoing active phase of ...russia's war against Ukraine since February 2022. In order to understand the pathological processes that occur in and outside the gunshot wound, we conducted an experimental study using mathematical simulation. The results presented in the article will help to choose the appropriate surgical management and improve the results of treatment. The aim of this study was to investigate and evaluate the damaging effect of a 5.45 mm 7N6M bullet and a 5.45 mm V-max expansive bullet using numerical modeling of wound canals in ballistic plasticine. The Ansys Explicit Dynamics engineering complex was used to simulate the dynamics of the bullet’s motion. The basic equations, solved by the explicit dynamic analysis, express the conservation of mass, momentum, and energy in Lagrange coordinates. Together with the material model and the set of initial and boundary conditions, they determine the complete solution to the problem. Taking into account that the initial velocity of the bullet is 1185 m/s at a mass of 3.9 g, we obtain energy 2740 J. All this energy acts at the area of the wound canal with a depth of 150 mm. Injury with a conventional 7N6M bullet is characterized by the fact that it passes through the block and loses only part of the kinetic energy. The simulation results showed that the velocity of the bullet at the outlet is 220 m/s. Taking into account the initial velocity of the bullet 918 m/s with a mass of 3.4 g, we obtain the kinetic energy acting on the walls of the wound canal with a depth of 200 mm of about 830 J. Mathematic analyses showed that the expansive bullet has a soft core that deforms and transfers all the kinetic energy to the tissues immediately after penetration into the tissues. The loss of kinetic energy of the bullet (ΔE, J) is defined as the difference between the kinetic energy at the time of injury (Ec, J) and the residual energy of the bullet when leaving the material (Er, J). Numerical modeling of wound ballistics in biological tissue simulators allows us to determine with high accuracy the features of wound canal formation and tissue response to damage of bullets having different kinetic energy, which contributes to the choice of adequate surgical management during surgery for gunshot wounds.
В течение 10 лет после аортокоронарного шунтирования (АКШ) 60 % венозных шунтов и 90 % трансплантатов внутренней грудной артерии (ВГА) остаются функционирующими. Частота прогрессирования ...проксимальных стенозов шунтированных артерий до полных окклюзий составляет 22 % при использовании ВГА как артериального анастомоза и 48 % в среднем после применения аутовенозных трансплантатов. В соответствии с литературными данными, при многофакторном анализе больные, перенесшие АКШ и подвергающиеся последующей коронарной ангиопластике, имеют более высокий риск вмешательства в отношении смертности и послеоперационных осложнений. Если реканализация артерии прошла успешно, смертность достигала 2,6 %, в случае частичного успеха – 5,2 %, а в случае неудачи летальность составила 8,2 %.
При вмешательстве у больных после АКШ предпочтительной является реканализация окклюзий нативных коронарных артерий, нежели аорто-коронарных трансплантатов.
В настоящей работе представлен анализ возможных интервенционных подходов к реканализации коронарного русла у больных после АКШ, обсужден собственный опыт и практические наработки. Реканализации хронических окклюзий коронарных артерий в различные сроки после АКШ с общей технической эффективностью 75 % подверглись 52 больных.
Vasorenal hypertension occurs approximately in 5% of patients, suffering arterial hypertension and in majority of them constitutes the consequence of the renal arteries stenosing atherosclerosis. ...Stenting constitutes the method of choice in the treatment of the renal artery stenosis. Endoprosthesis of renal artery was performed in 113 patients, in 10 of them--bilateral stenting. Angiographic effect was achieved in more than 98% of observations and the clinical one--in more than 85%. Severe intraoperative complications were absent, all the patients are alive. In 13 patients the restenosis in the stent had occurred in 6-18 months after the operation, presenting by the clinical signs recurrence. To these patients the balloon angioplasty in the stent was accomplished. The depiction of technical peculiarities of the diagnosis and the procedure of the renal arteries stenting was suggested. According to modern recommendations of ACC/AHA, the stenting is indicated in the patients, suffering renal artery stenosis, and cardiac weaknesparoxysms, progressing arterial hypertension, unstable stenocardia, bilateral arterial affection. In the absence of symptoms, the efficacy of revascularization is not proved.
Endovascular treatment of vasorenal hypertension (VRH) constitutes the operation of choice in selected groups of patients. In the Centre there was conducted a renal arteries (RA) stenting, using ...antiembolic devices in 6 patients (4 men and 2 women). There were applied distal filters Accunet (Abbot Vascular, USA) 12 mm in length with diameter of a cell 150 mcm. The devices application, having a net structure, is possible in optimal anatomy of artery (rectangular branching), significant stenosis of RA, primarily bad renal function, a presence of anatomically loose plaque in RA, atherosclerotic ulceration of the abdominal aorta wall. There are limitations of their application: an ischemia while performing of the procedure, complexity of the stenotic region visualization, as well as a control of a precise delivering and implantation of a stent-system and a possibility of the embolism occurrence after extraction of occluding balloon.
to develop taking into account the specifity of exposure conditions a new algorithm for interventional cardiologists who use the X-ray protective clothes.
modelling of the typical conditions of ...radiation exposure of interventional cardiologist wearing protective clothes during the interventions, providing Monte-Carlo computations of organ doses and dosimeters readouts.
partial dose values for all possible radiation conditions and relative frequency weight coefficients for each condition were obtained by Monte-Carlo method.
flexible and adaptive methodology for algorithm developing was proposed, a more specific algorithm was obtained for typical radiation conditions occuring under the interventional cardiology procedures. This algorithm well corresponded to experimental measurements demonstrating at that less conservatism comparing to other known algorithms.
Резюме. Работа посвящена анализу отдаленных результатов эндопротезирования брюшного отдела аорты у пациентов с аневризмой абдоминального отдела. Отмечены позитивные 10-летние результаты наблюдения, ...динамика аневризматического мешка после вмешательства, изучена необходимость в повторных эндоваскулярных вмешательствах, а также их особенности и показания. Представлены результаты морфологических исследований стенки аорты и связь их со стабильностью аневризматического мешка.
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