Цель. Оценить вклад воспаления в клинические результаты радиочастотной аблации (РЧА) фибрилляции предсердий (ФП). Материал и методы. Обследовано 274 пациента, поступивших в клинику с диагнозом идиопатическая форма ФП, из которых только у 67 (24,5%) этот диагноз был подтвержден на первом этапе обследования. Всем пациентам проведены внутрисердечное исследование и РЧА ФП, эндомиокардиальная биопсия (ЭМБ) с гистологическим и иммуногистохимическим исследовани-ями для определения иммунофенотипа клеток инфильтрата в эндомиокарде и выявления экспрессии антигенов кардиотропных вирусов: к парвовирусу В19, энтеровирусу, вирусу герпеса человека 1 и 2-го типа, аденовирусу, цито-мегаловирусу, вирусу Эпштейна-Барра. Оценивалась эффективность катетер-ного лечения, возникновение ранних и поздних рецидивов предсердных тахиаритмий. Результаты. Гистологических изменений в миокарде правого желудочка, по данным эндомиокардиальной биопсии, не обнаружено у 9 (13,4%) пациен-тов. У 26 (38,8%) выявлены фиброзные изменения миокарда: у 11 (42,3%) -преимущественно периваскулярный фиброз, у 8 (30,8%) -мелкоочаговый, у 7 -(26,9%) -перимускулярный. Воспалительные изменения (согласно Далласским критериям) отмечены у 32 (47,8%) пациентов, из которых у 9 (28,1%) обнаружена лимфоцитарная инфильтрация (менее 14 лимфоцитов в мм 2 ). У одного из этих пациентов (3,1%) было выявлено сочетание экспрес-сии вируса простого герпеса человека 2-го типа и вируса Эпштейна-Барра. У 23 пациентов (34,3%), найден миокардит, из них у 18 (78,3%) обнаружена экспрессия вируса. У одного (5,6%) пациента выявлена экспрессия трех виру-сов, у шести (33,3%) пациентов -двух вирусов, у 11 пациентов (61,1%) -одного вирусного антигена. Срок наблюдения за пациентами в среднем соста-вил 19,3±3,7 месяцев. Эффективность первичной РЧА у пациентов с интакт-ным миокардом составила 88,9%, с фиброзными изменениями различной степени выраженности -46,2%, при наличии критериев миокардита -34,4%. Ранние рецидивы аритмии отсутствовали при неизмененном миокарде. При наличии фиброзных изменений чаще регистрировались ранние рецидивы (53,8%) и реже -поздние (34,6%). При наличии воспалительных изменений выявлена обратная зависимость, чаще выявлялись поздние рецидивы (53,1%) и реже -ранние (37,5%). Заключение. По нашим данным, только 24,5% пациентов не имеют заболева-ний, способствующих развитию аритмии. Проведение гистологического исследования показало, что только около 10% пациентов имеют идиопатиче-скую форму аритмии, у половины пациентов отмечаются субклинические воспалительные изменения миокарда, у остальных выявлены фиброзные изменения. Наличие воспалительных и фиброзных изменений в миокарде увеличивает количество ранних и поздних рецидивов аритмии и, соответ-ственно, вдвое уменьшает эффективность РЧА ФП.Российский кардиологический журнал 2014, 12 (116): 7-12 http://dx

With the participation: All-Russian Scientific Society of Specialists in Clinical Electrophysiology, Arrhythmology and Pacing, Russian Association of Cardiovascular SurgeonsEndorsed by: Research and Practical Council of the Ministry of Health of the Russian Federation

Aim. We aimed to assess safety and effectiveness of class III antiarrhythmic drug Refralon for conversion of atrial fibrillation (AFib) and flutter (AFl) in post-registration trial and to compare data of primary center (National medical research center in cardiology) with data of other hospitals.Material and Methods. We performed retrospective cohort study in 727 patients (451 enrolled in primary center and 276 enrolled in other hospitals) admitted between June 24, 2014 and June 24, 2019. Refralon was administered for conversion of AFib and AFl in intense care units in escalating doses (10-30 micrograms/kg) intravenously.Results. Conversion of AFib and AFl into sinus rhythm was achieved in 53,6% after administration of 10 mcg/kg dose, in 73% after administration of 20 mcg/kg dose and in 91,6% after administration of Refralon in dose up to 30 mcg/kg. No mortality and no major adverse cardiac events registered in our study. Asystole >3.0 sec observed in 5% (35 of 727) of patients): in 5% (24 of 451) of patients enrolled in primary center and in 4% (11 of 276) of patients enrolled in other hospitals; 95% confidence interval (CI) [-0.09; 0.113]. Asystole> 5.0 s observed in 1.7% of patients who further required non-urgent implantation of a permanent pacemaker due to manifestations of sinus node dysfunction. Cardiac conduction disturbances (exclusively sinus bradycardia) were registered in 7% (53 of 727) patients: in 8% (37 of 451) of patients enrolled in primary center and in 6% (17 of 276) of patients enrolled in other hospitals; 95% CI: [-0.1; 0.15]. Only 0.14% of patients had symptomatic sinus bradycardia that resolved after atropine injection. Ventricular arrhythmias (exclusively Torsade de pointes tachycardia in excessive QT interval prolongation) were registered in 1.7% (12 of 727) patients: in 2% (9 of 451) of patients in primary center and in 1% (3 of 276) of patients of other hospitals; 95% CI: [-0.06; 0.08]. QTc interval prolongation to values >500 ms documented in 19% (138 of 727) of patients: in 21% (95 of 451) of patients in primary center and in 16% (43 of 276) of patients in other hospitals; 95% CI: [-0.13; 0.24].Conclusion: In post-registration multicenter trial Refralon demonstrated good safety profile in conversion of AFib and AFl. Potential risk of TdP tachycardia mandates precautions with the use of the drug. In other hospitals Refralon did not demonstrate lower safety than in primary medical center.

Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): None Previous studies have shown that an increase of epicardial adipose tissue (EAT) volume is an independent risk factor of atrial fibrillation (AF) occurrence. However, there is no reliable data about the relationship between EAT and AF recurrence after catheter ablation (CA). Also, there are no studies of the possibility of using of CT radiomics of EAT, in particular of the quantitative assessment of EAT textural changes, for prognosis of CA outcomes in patients with AF.  Thus, the aim of the present study was to estimate the association of CT-radiomics features of EAT with probability of AF recurrence after catheter ablation. Materials and Methods The prospective research included 46 patients (42 males and 4 females, mean age 42.4 ± 9.36) with drug-refractory lone AF referred for catheter ablation (CA). Before CA all patients underwent multislice CT-angiography for preoperative evaluation of cardiac and vessels anatomy and volumes. Images were acquired using a 64-detector CT scanner (GE Discovery NM/CT 570c, GE Healthcare, Milwaukee, WI, USA). Imaging parameters included a gantry rotation time of 400 ms, tube voltage of 120 mA, slice thickness 1.25 mm. For evaluation of EAT only native images (contrast-free scans) without ECG synchronization were analyzed. Epicardial adipose tissue segmentation was performed by 3D-Sliser software and the SliserRadiomics module (version 4.10.2). From CT images we quantified EAT volume and 93 radiomic features, including subgroups of first-order statistics, GLCM, GLDM, GLRLM, GLSZM and NGTDM parameters. All patients were followed-up prospectively for 12 months after the CA. A blanking period of 3 months was applied. The criteria of AF recurrence were AF episodes of more than 30 sec duration. Results. Recurrence of AF was registered in 26 patients. After the end of the follow-up, we divided study population on those with (Group 1) and without (Group 2) AF recurrence. EAT volume and attenuation values for Group 1 were 176.6 ± 56.9 sm3 and -77.47 ± 2.2 HU respectively; for Group 2 were 174.05 ± 73.3 sm3 and -78.42 ± 3.3 HU respectively, with no significant differences (p < 0.05). In the same time, 16 of 93 CT radiomics EAT parameters were significantly different between Group 1 and Group 2 and were significantly associated with AF recurrence after CA according to univariable logistic analyses. Multivariate regression analysis demonstrated that only Gray Level Non-Uniformity Normalized (GLNUN of GLSZM) parameter was an independent predictor of AF recurrence (Odds ratio 1.0022, 95%Cl 1.0006 to 1.0038, p = 0.0013);  ROC-curve analysis data showed that GLNUN > 1227.2 indicates high probability of AF recurrence during 12 months (sensitivity 84.2 %, specificity 70.8 %, AUC:0.765; p = 0.001). Conclusion radiomic biomarkers of EAT have a potential to serve as a predictors of AF recurrence after CA.

<p><strong>Background.</strong> Atrial fibrillation (AF) is combined with an inflammatory process that occurs in the myocardium. Diagnosis of histological changes, including inflammatory changes, in the myocardium is a complex task in the field of modern medicine. The only reliable way of determining the inflammatory changes in the myocardium is endomyocardial biopsy (EMB). As per our literature review, there are no data on the effect of histological changes in the myocardium on the efficacy of interventional treatment for AF. Moreover, assessing the dynamics of EMB results allows us to approach the treatment of patients in greater detail, thereby lowering the risk of the development and progression of serious cardiac pathologies, particularly AF.</p><p><strong>Aim.</strong> To study the effectiveness of catheter treatment for ‘idiopathic’ AF, depending on the dynamics of histological changes in the myocardium.</p><p><strong>Methods.</strong> We enrolled 48 patients with an ‘idiopathic’ form of AF; the median patient age was 39.0 y (33.5–48.0 y). Of these, 42 (87.5 %) were men and 6 (12.5 %) were women. The median duration of arrhythmic history was 4.0 y (2.0–7.0 y). All the patients underwent radiofrequency isolation of the pulmonary veins (Rcil) and EMB from the right ventricle. Histological tests, using the criteria of Cristina Basso, and immunohistochemical (IHC) tests were performed to determine the antigens of the following viruses: herpes simplex virus (HSV) types 1, 2 and 6, enterovirus (EV), Epstein-Barr, adenovirus and parvovirus (PV). After 6 mon, EMB, histological and IHC studies were repeated. Depending on the clinical form of AF, the patients are divided into the following three groups: group 1—paroxysmal form [21 (43.7 %) patients], group 2—persistent [13 (27.1 %) patients], group 3—long-term persistent [14 (29.2 %) patients]. Based on the results of the observation and evaluation of effectiveness, all the groups were divided into the following three subgroups: a—absence of AF during 12 mon of observation, b—early arrhythmia recurrences were registered during the first 3 mon of observation, c—presence of late arrhythmia recurrence after 3 mon of observation.</p><p><strong>Results.</strong> According to the histological criteria for active lymphocytic myocarditis identified in the subgroups, there were <br />5 patients (35.7 %) in 1a, 2 (50 %) in 1b, 6 (75 %) in 2a, 2 (66,7 %) in 2b, 7 (70 %) in 3a, 2 (66.7 %) in 3b, and 1 (100 %) in 3c. The rest of the patients showed signs of lymphocytic infiltration. After 6 mon, only in group 2a, there was a significant reduction in the number of patients with active lymphocytic myocarditis (p &lt; 0.05). All the patients showed fibrotic changes and expression of HSV 6 and EV antigens of varying severity; this persisted till after 6 mon. The overall effectiveness of the surgical treatment was 66.7 % for paroxysmal, 61.5 % for persistent and 71.4 % for long-term persistent forms of AF during 12 mon of follow-up.</p><p><strong>Conclusion.</strong> Patients with ‘idiopathic’ AF show inflammatory changes in the myocardium, and 48.7 % met the criteria for myocarditis. All the patients showed the expression of viral antigens and the development of fibrosis that met the criteria for post-inflammatory changes. A repeat study that was conducted after 6 mon showed no significant dynamics of inflammatory and fibrotic changes. Despite the presence of inflammatory changes in the myocardium, the effectiveness of catheter treatment was 66.7 % for paroxysmal, 61.5 % for persistent and 71.4 % for long-term persistent forms of AF.</p><p>Received 29 April 2020. Revised 1 June 2020. Accepted 3 June 2020.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Conception and design: A.E. Shelemekhov, R.E. Batalov<br />Data collection and analysis: A.E. Shelemekhov, Yu.V. Rogovskaya, S.Yu. Usenkov, E.A. Archakov, M.S. Rebenkova <br />Drafting the article: A.E. Shelemekhov<br />Statistical analysis: A.E. Shelemekhov, A.M. Gusakova<br />Critical revision of the article: R.E. Batalov, Yu.V. Rogovskaya, A.M. Gusakova<br />Final approval of the version to be published: A.E. Shelemehov, R.E. Batalov, Yu.V. Rogovskaya, S.Yu. Usenkov, E.A. Archakov, A.M. Gusakova, M.S. Rebenkova</p>