Взаимосвязь структурных изменений миокарда левого предсердия и эффективности криоаблации при персистирующей фибрилляции предсердий

Introduction. High-resolution contrast-enhanced cardiac magnetic resonance imaging reveals left atrial fibrosis, the severity of which may be related to the effectiveness of catheter ablation.Aim. To study the structural changes of the left atrium myocardium according to magnetic resonance imaging with contrast in patients with persistent atrial fibrillation before balloon cryoablation and compare the results with the effectiveness of the intervention.Materials and methods. The study included 89 patients with persistent form of atrial fibrillation. The patients were randomized into two groups: in the 1st, the pulmonary veins cryoablation was performed (n = 39 (53.4%)); in the 2nd, the pulmonary veins and posterior wall of the left atrium cryoablation was performed (n = 34 (46.6%)). All patients before cryoablation underwent cardiac magnetic resonance imaging with delayed contrast using a high-resolution MR pulse sequence. The clinical efficacy of the intervention was evaluated after 12 months after the cryoablation.Results. The severity of fibrotic myocardial lesion of the left atrium before balloon cryoablation was 0.7% [0; 3,07]. Overall efficiency of the intervention rate was 57.1%. Cryoablation was most effective (59.5%) in patients severity of fibrosis less than 20% and least effective (50%) severity of fibrosis more than 20%. Risk factors for atrial fibrillation recurrence after cryoablation were: early atrial fibrillation recurrence, female sex, the maximum atrial fibrillation duration more than 3 months, stroke/TIA.Conclusion. The severity of left atrial fibrosis more than 20%, early recurrence of atrial fibrillation in the first 3 months after the cryoablation, female sex, the duration of the maximum atrial fibrillation episode more than 3 months, and a history of stroke/transient ischemic attack may be associated with recurrence of AF during the period observation 3–12 months.Введение. Магнитно-резонансная томография (МРТ) сердца с отсроченным контрастированием высокого разрешения позволяет выявить фиброз левого предсердия, выраженность которого может быть связана с эффективностью катетерной аблации.Цель. Изучить структурные изменения миокарда левого предсердия по данным МРТ с контрастированием у пациентов с персистирующей формой фибрилляции предсердий и сопоставить результаты с эффективностью баллонной криоаблации.Материалы и методы. В исследование включены 73 пациента с персистирующей формой фибрилляции предсердий. Пациенты были разделены на две группы: в 1-й выполнялась криоаблация легочных вен (n = 39 (53,4%)); во 2-й – криоаблация легочных вен и задней стенки левого предсердия (n = 34 (46,6%)). Всем пациентам до криоаблации проводилась МРТ сердца с отсроченным контрастированием высокого разрешения. Клиническая эффективность вмешательства оценивалась через 12 мес. после криоаблации.Результаты. Выраженность фиброза левого предсердия до вмешательства составляла 0,7% [0; 3,07]. Общая эффективность вмешательства составила 57,1%. Вмешательство было наиболее эффективным (59,5%) у пациентов с выраженностью фиброза до аблации менее 20% и наименее эффективным (50%) – при фиброзном поражении более 20%. Факторами риска рецидива фибрилляции предсердий после криоаблации явились: рецидив фибрилляции предсердий в первые 3 мес. после вмешательства, женский пол, длительность максимального эпизода фибрилляции предсердий более 3 мес. и инсульт / транзиторная ишемическая атака в анамнезе.Заключение. Выраженность фиброза левого предсердия более 20%, ранний рецидив фибрилляции предсердий в первые 3 мес. после вмешательства, женский пол, длительность максимального эпизода фибрилляции предсердий более 3 мес. и инсульт / транзиторная ишемическая атака могут быть связаны с рецидивом фибрилляции предсердий в период наблюдения 3–12 мес

2020 Clinical practice guidelines for Pulmonary hypertension, including chronic thromboembolic pulmonary hypertension

Russian Society of Cardiology (RSC)With the participation: Association of Cardiovascular Surgeons of Russia, Russian Respiratory Society, Federation of Anesthesiologists and Resuscitators, Association of Rheumatologists of Russia, National Congress of Radiation Diagnosticians

2020 Clinical practice guidelines for Hypertrophic cardiomyopathy

Russian Society of Cardiology (RSC)With the participation: Russian Association of Cardiovascular SurgeonsEndorsed by: Research and Practical Council of the Ministry of Health of the Russian Federation Task Force: Gabrusenko S.A. (Chairman), Gudkova A.Ya.* (Chairman), Koziolova N.A. (Chairman), Alexandrova S.A., Berseneva M.I., Gordeev M.L., Dzemeshkevich S.L., Zaklyazminskaya E.V., Irtyuga O.B., Kaplunova V.Yu., Kostareva A.A., Krutikov A.N., Malenkov D.A., Novikova T.N., Saidova M.A., Sanakoev M.K., Stukalova O.V

2020 Clinical practice guidelines for Myocarditis in adults

Russian Society of Cardiology (RSC)With the participation: Eurasian Association of Therapists (EUAT), Society of Specialists in Heart Failure (OSSN), Russian Scientific Medical Society of Therapists (RNMOT), Russian Society of Pathologists, Russian Society of Radiologists and Radiologists (RSR)Endorsed by: Research and Practical Council of the Ministry of Health of the Russian Federatio

Numerical method of estimation of parameters of the nonlinear differential operator of the second order

The main problem of mathematical simulation is the problem of nonlinear estimation of parameters of the different physical systems. The article contains new numerical method of parameters estimation of the nonlinear differential operator of the second order with the dissipative force, proportional to $n$-motion speed level assessment. Mean square estimation of coefficients of the generalized regression model constructed taking into account the difference equations describing results of measurements of a pulse response of system is the cornerstone of the numerical method. Two landmark procedure of differentiated estimation of parameters of dynamic process realized in a method allow to provide high adequacy of the constructed model to data of an experiment. Application of the developed numerical method allows to increase significantly (several times) the accuracy of estimates of parameters of the nonlinear differential operator in comparison with the known methods due to elimination of the offset in estimates caused by use of approximation in case of simulation of an envelope of vibration amplitudes

Deep multilevel wet etching of fused silica glass microstructures in BOE solution

Abstract Fused silica glass is a material of choice for micromechanical, microfluidic, and optical devices due to its chemical resistance, optical, electrical, and mechanical performance. Wet etching is the key method for fabricating of such microdevices. Protective mask integrity is a big challenge due extremely aggressive properties of etching solution. Here, we propose multilevel microstructures fabrication route based on fused silica deep etching through a stepped mask. First, we provide an analysis of a fused silica dissolution mechanism in buffered oxide etching (BOE) solution and calculate the main fluoride fractions like $${HF}_{2}^{-}$$ HF 2 - , $${F}^{-}$$ F - , $${(HF)}_{2}$$ ( H F ) 2 as a function of pH and NH4F:HF ratio. Then, we experimentally investigate the influence of BOE composition (1:1–14:1) on the mask resistance, etch rate and profile isotropy during deep etching through a metal/photoresist mask. Finally, we demonstrate a high-quality multilevel over-200 μm etching process with the rate up to 3 μm/min, which could be of a great interest for advanced microdevices with flexure suspensions, inertial masses, microchannels, and through-wafer holes

The effectiveness of cardiac resynchronization therapy in patients with chronic heart failure of various origin depending on the structural myocardial injury in cardiac magnetic resonance imaging

Aim. To assess the effect of the size and pattern of myocardial structural injury, determined by magnetic resonance imaging (MRI), on response to cardiac resynchronization therapy (CRT) in patients with ischemic and non-ischemic heart failure (HF).Material and methods. Forty seven patients with ischemic and non-ischemic HF (age 62,3±8,9 years (mean±SD), 44,6% females and 55,4% males), left ventricle (LV) ejection fraction <35%, QRS complex >130 ms, and sinus rhythm were included in the study. Late-gadolinium enhancement-cardiovascular magnetic resonance (LGE-CMR) was undertaken to evaluate myocardial scar prior to CRT devices implantation. All CMR analysis was performed on CVI42 software. According to signal intensity, fibrosis zone and “grey zone” were defined for quantitative analysis (proportion and mass) of injury. Scar zone included fibrosis zone and “grey zone”. Scar location was assessed using a 16-segmentLV model. Response was defined as a reduction inLV end systolic volume of >15% at 6 months follow-up and HF functional class amelioration.Results. In nonresponse group there was significantly higher proportion and mass of total scar (median 4% [2,5; 19] vs 24% [7; 44], p=0,012,6 g [3,5; 32,5] vs41 g [8; 86], p=0,013)), fibrosis zone (median 0% [0; 3,5] vs 8% [0; 19], p=0,01,0 g [0; 6] vs14 g [0; 34], p=0,014) and “grey zone” (4% [2,5; 15] vs 15% [7; 23], p=0,018,6 g [3,5; 27,5] vs23 g [8; 39], p=0,25). Response proportion in non-ischemic HF patients was higher than in ischemic HF patients (78,5% vs 28,5%, p<0,01). Response to CRT was less in patients with posterolateral scar, more specifically in segments 4,5,6,11,12,15,16 (p<0,05). CRT response in ischemic HF did not depend on size of myocardial structural injury, but depend on scar localization. Lateral scar was associated with poor response. In non-ischemic HF, proportion and mass of fibrosis zone was less in responder group (median 0% [0; 1] vs 8,5% [0; 11], p<0,05,0 g [0; 1] vs14,5 g [0; 22], p<0,05.Conclusion. Response to CRT is significantly higher in non-ischemic than in ischemic HF patients. Nonresponse to CRT is associated with posterolateral scar, regardless of the HF origin. In patients with non-ischemic HF, size of fibrosis zone is lower in the responder group. In patients with ischemic HF, size ofLV structural injury does not affect the CRT efficiency, but lateral scar is associated with CRT nonresponse