The experience of radiofrequency ablation of atrial tachycardia focus with the use of high-density myocardial mapping

The article presents a case of successful treatment of focal atrial tachycardia by radiofrequency ablation using high-density myocardial mapping. The aim of the work was to evaluate the possibilities of high-resolution myocardial mapping by EnsitePrecision® navigation system in the treatment of complex arrhythmias. The analysis of clinical data and results of electrophysiological examination of a 29-year-old patient with continuous recurrent focal atrial tachycardia was carried out. The patient was admitted with complaints of heart rate disorders and frequent short attacks of palpitations. According to electrocardiography, frequent short paroxysms of focal atrial tachycardia were revealed. The patient was taken for electrophysiological examination and radiofrequency ablation of the focus of atrial tachycardia. The focus of atrial tachycardia was located in the anterior septal part of the left atrium, which is a rare localization. After radiofrequency ablation tachycardia was terminated, no complications and recurrences were registered. The patient was discharged with the sinus rhythm. Navigation system EnsitePrecision® enables conducting high-density myocardial mapping, which helps to accurately determine the localization of the source of tachycardia. The radiation load on the patient and ablation time are reduced, which reduces the frequency of complications from the procedure

Safety and Tolerability of Implanted Subcutaneous Cardioverter-Defibrillator Systems

Aim. To study the safety and tolerability of the subcutaneous implantable cardioverter defibrillator (S-ICD) after implantation.Material and methods. The results of 33 patients with implanted S-ICD 6 months follow-up. The criteria for inclusion in the observational study were: age over 18 years, indications for primary or secondary prevention of sudden cardiac death. The exclusion criteria were indications for implantation of transvenous ICD (patients with sustained monomorphic ventricular tachycardia, the need for anti-bradycardia or resynchronization therapy), as well as patients with a QRS complex of more than 130 msec. All patients underwent a standard preoperative examination (routine blood tests, chest X-ray, transthoracic echocardiography), quality-of-life questionnaires and transesophageal echocardiography. At follow-up, patients were examined after 6 months after implantation, the device was interrogated and a quality-of-life questionnaire was completed. All episodes of shock therapy and complications were documented.Results. Male patients predominated (84%), with a mean age of 57 [43;62] years. Left ventricular ejection fraction was 30% [26;34]. The mean QRS duration was 100 [94;108] msec. According to the of 24-hour Holter ECG monitoring, episodes of unstable VT were recorded in 42.4% of patients. The most common indications for S-ICD implantation were dilated (33%) and ischemic cardiomyopathy (42%). Primary prevention was indicated in 97% of patients. At the end of the implantation of the S-ICD, the patients underwent a defibrillation test and device configuration. In 63.6% of cases, during automatic tuning, the device selected the primary perception vector. In 27.2% of patients, optimal recognition of the subcutaneous signal was observed in the secondary vector, and in 9.2% of patients, the alternative vector was favorable. All patients underwent two-zone programming. The conditional shock zone was programmed at an average rate of 192 beats/min (range 180-210 beats/min) and the shock zone was programmed at an average rate of 222 beats/min (range 220-240 beats/min). Perioperative complications occurred in two patients. During the follow-up period, no shocks were recorded in 27 patients. Adequate shocks for 6 months were recorded in two patients. During 6 months of observation, one lethal outcome was noted due to complications of viral pneumonia. During the observation period, there were no rehospitalizations for cardiovascular diseases.Conclusion. The use of S-ICD, even in patients with structural myocardial disease who do not require antibradycardia pacing, is effective in preventing SCD. The number of inadequate discharges and the number of complications in clinical practice is comparable to the data of multicenter studies. S-ICD implantation was not accompanied by a decrease in quality of life. Careful selection of candidates, along with state-of-the-art device programming, is an important parameter for the selection and success of S-ICD application

Genetic, Epigenetic and Transcription Factors in Atrial Fibrillation

Atrial fibrillation (AF) is one of the most common arrhythmia that occurs in patients with cardiovascular diseases. Congenital forms of AF are quite rare. Many studies have shown that genetic, epigenetic and transcription factors may play an important role in the development and the progression of AF. In our review, studies have been conducted on the identification of mutations in ionic and non-ionic channels, possibly associated with AF. These mutations were found only in isolated groups of patients with AF, and in general, monogenic forms of AF are a rare subtype of the disease. Genomic association studies have helped to identify potential links between single nucleotide polymorphisms and AF. The risk of AF in the general population is likely to be determined by the interaction between environmental factors and many alleles. In recent years, the emergence of a genome-wide associative studies has significantly expanded the understanding of the genetic basis for the inheritance of AF and has led to the emergence of new evidence of the important role of genetic factors in the development of AF, in the risk stratification of AF and the recurrence of AF. Epigenetic factors are also important in AF. Epigenetic therapy aimed at treating a disease through exposure to epigenome is currently under development. A newly emerged area of ablatogenomics includes the use of genetic profiles that allow assessing the likelihood of recurrence of AF after catheter ablation. The results of genetic studies in AF show that, in addition to their role in the appearance of congenital heart pathologies, transcription factors play an important role in the pathogenesis of AF

Atrial Fibrillation: Development Mechanisms, Approaches and Prospects of Therapy

Atrial fibrillation (AF) is the most common arrhythmia. It is diagnosed in more than 33 million people worldwide and is the leading cause of hospitalization for arrhythmias. AF is characterized by fast and irregular atrial activation without discrete P-waves at a surface electrocardiography. AF pathophysiological mechanisms are very complex and include the dynamic interaction between arrhythmia substrate and triggers. Consequently, the clinical search for effective therapeutic targets should include the entire process of the onset and progression of the disease: from the first paroxysms to the development of a stable permanent form of AF

Rotor Drivers in Induction and Maintenance of Atrial Fibrillation

Atrial fibrillation is the most common arrhythmia in clinical practice. It is associated with an increased risk of stroke, chronic heart failure, and sudden cardiac death. Our options of restoring and maintaining sinus rhythm have a very limited effect, both in the case of antiarrhythmic and catheter treatment. Catheter ablation has proven to be a more effective approach than antiarrhythmic therapy. The success rate of the procedure reaches 70%. However, radiofrequency ablation is associated with a risk of complications, with 4.5% of patients likely to develop major complications, including tamponade (1.31%), femoral pseudoaneurysm (0.71%), and death (0.15%). Given the generally recognized dominant role of the pulmonary veins in the induction of atrial fibrillation, their electrical isolation has become the recommended tactic of the catheter approach. In the case of patients with paroxysmal form of atrial fibrillation, the success rate of the procedure reaches 87%. Unfortunately, in the case of persistent forms of atrial fibrillation, the effectiveness of the primary procedure decreases to 28% and reaches 51% with repeated interventions. In addition to the anatomically oriented isolation of the pulmonary veins, a number of strategies have been proposed to reach the secondary zones of atrial fibrillation induction. The results of recent studies on the effectiveness of strategies for ablation of rotor regions and their role in the induction and maintenance of AF may lead to the further development of catheter ablation techniques and an individual radiofrequency ablation approach in a particular patient

Surgical treatment of incisional tachycardia and atrial fibrillation in patients with mitral valve prosthesis: should we be scared?

Mitral valve disease, including dysfunction of the mitral valve, is often accompanied by atrial fibrillation. Among the patients with prosthetic mitral valves, atrial fibrillation occurs in 30–50% cases. Development of atrial arrhythmias and incisional tachycardia in the early and late postoperative periods can significantly influence patients’ rehabilitation and prognosis. Our clinical case describes a patient with a mechanical mitral valve and incisional tachycardia, which led to progression of heart failure and reduced left ventricular systolic function. The patient underwent catheter ablation with non-invasive myocardium mapping. The case reveals the potentials of treatment of incisional tachycardia and atrial fibrillation, which do not respond to drug therapy. Modern methods of visualization enable the cardiac surgeons to reduce possible intraoperative risks and development of complications in this group of patients

Nonfluoroscopic catheter ablation in patients with atrial fibrillation

The article demonstrates available literature data on the nonfluoroscopic catheter ablation of atrial fibrillation (AF). The main disadvantages of standard fluoroscopic catheter ablation are shown. The research results on the use of intracardiac echocardiography are presented. The first experience of using the fluoroscopy-free procedure in Russia as a pilot study is also presented. During the period from December 2017 to December 2019, 28 radiofrequency ablations and 40 pulmonary vein cryoballoon ablations were performed without fluoroscopy using threedimensional imaging and intracardiac echocardiography. Despite the small number of large studies in this area, clinical cases described in the literature, as well as their own results, demonstrate the safety of using three-dimensional imaging in combination with intracardiac echocardiography as an alternative to fluoroscopy. Application of the approach is of undoubted practical interest and requires further study in large studies

Transcatheter “valve-in-valve” implantation of bioprosthesis in failed surgical tricuspid bioprosthesis (first experience in Russia)

Aim. In the issue we report first in Russia experience of transcatheter “valve-invalve” implantation (TVIV) for treatment of severe tricuspid stenosis due to the structural deterioration of surgical tricuspid bioprosthesis.Material and methods. TVIV was performed in 4 high-risk redo patients (1 to 3 previous sternotomies) of various ages across (18-68 years) with structural deterioration of surgical tricuspid bioprosthesis.Results. Technical success was achieved in 100% cases. Diastolic gradients on tricuspid valve markedly decreased in all patients. Peak transtricuspidal gradient decreased from 20,4 to 10 mmHg in average. Clinical improvement as assessed by 6-minute walk test after TVIV was observed in 3 patients with congestive heart failure. In 1 patient with asymptomatic right ventricle dysfunction TVIV resulted in the enhancement of echocardiographic parameters.Conclusion. TVIV is a mininvasive alternative to conventional surgical tricuspid valve redo replacement. Based on available data including own experience TVIV should be considered an effective and safe treatment option for failed TV bioprostheses in high-risk patients of different age. Further studies are needed to assess long-term results of the method

Торакоскопическая аблация для лечения пациентов с изолированной формой фибрилляции предсердий в России

Актуальность. Хирургические вмешательства с использованием эндоскопической техники демонстрируют высокую эффективность при лечении пациентов с персистирующей формой фибрилляции предсердий. Минимальная травматичность торакоскопических процедур способствует популяризации подобных вмешательств по всему миру. В настоящее время торакоскопические вмешательства стали доступны для пациентов в Российской Федерации.Цель. Собрать и систематизировать данные о развитии торакоскопической аблации в Российской Федерации, выполняемой для лечения пациентов с изолированной формой фибрилляции предсердий.Методы. Выполненная работа охватила период операций, проведенных отечественными кардиохирургами до 1 января 2018 г. Для сбора данных респонденты заполняли регистрационную форму. В анкете регистрировали даты выполнения процедур, форму фибрилляции предсердий, наличие предшествующих катетерных процедур, инструмент для проведения операции, схему нанесения аблационных линий, метод закрытия ушка левого предсердия, большие осложнения вмешательства. Сбор регистрационных форм осуществлен посредством электронной переписки.Результаты. Получены и проанализированы данные 652 торакоскопических аблаций, выполненных в 10 кардиохирургических центрах России. Большую часть операций (92%) провели у пациентов с персистирующей формой фибрилляции предсердий. Аблационные линии наносились по двум основным схемам — Dallas Lesion Set и Box Lesion Set. Ушко левого предсердия выключено из внутрисердечного кровотока при помощи различных методов у 90,4% пациентов. Значимые осложнения, развившиеся главным образом на этапе освоения методики, зарегистрированы у 27 (4%) пациентов.Заключение. Представленная работа является первой попыткой собрать и систематизировать данные о новом методе хирургического лечения пациентов с фибрилляцией предсердий. Полученные данные позволяют сделать вывод, что торакоскопическая аблация становится распространенным методом хирургического лечения пациентов с изолированной формой фибрилляции предсердий в России. Этап освоения методики сопровождается осложнениями в любом кардиохирургическом центре. Тем не менее количество осложнений, даже на этапе освоения методики, остается на минимальном уровне, позволяющем рекомендовать торакоскопическую аблацию для лечения многочисленной группы пациентов с фибрилляцией предсердий.Поступила в редакцию 13 июня 2018 г. Исправлена 22 июля 2018 г. Принята к печати 23 июля 2018 г. Финансирование Исследование не имело спонсорской поддержки.Конфликт интересовАвторы заявляют об отсутствии конфликта интересов.Вклад авторовКонцепция и дизайн работы: О.Ю. Пиданов, А.В. Богачев-ПрокофьевСбор и анализ данных: Д.А. Елесин, О.А. Бобровский, П.А. Шиленко, П.А. Дурыгин, А.С. Зотов, C.А. Вачев, В.Е. Вайкин, С.Е. Мамчур, О.В. Сапельников, Д.О. БыстровНаписание статьи: О.Ю. ПидановРедактирование статьи: А.В. Богачев-Прокофьев, Э.А. ИваницкийСтатистическая обработка данных: О.Ю. ПидановУтверждение окончательного варианта статьи: О.Ю. Пиданов, А.В. Богачев-Прокофьев, Д.А. Елесин, Э.А. Иваницкий, О.А. Бобровский, П.А. Шиленко, П.А. Дурыгин, А.С. Зотов, C.А. Вачев, В.Е. Вайкин, С.Е. Мамчур, О.В. Сапельников, Д.О. Быстров</p