Aim. Current registry is the continued national study on cryoablation in atrial fibrillation (AF). The aim of the project is assessment of safety and efficacy of cryoballoon ablation of pulmonary veins from AF treatment in real clinical practice prospective observation. Material and methods. The project has been developed for prospective inclusion of the data to guarded automatic informational system, on clinical data of patients, ablation parameters, repeat ablation and results of 12-month follow-up. To participate in the project in January of 2017, the representatives of 33 in-patient facilities were invited, that routinely perform the procedure. Results. Twenty five institutions confirmed their participation, and by December of 2017, the database was completed by specialists from 13 clinics: information on the ablation procedure and outcomes is included for 451 patient. The enrollment is ongoing with estimated end by January 2019; prospective follow-up to be completed by January 2020. Conclusion. Prospective registry of AF cryoablation is important for gathering of experience and common analysis of the procedures throughout the country. Detailed analysis will make it to reveal predictors of efficacy and methods for procedural risk decrease.

A retrospective study involving 40 patients, based on the initial division of the patients into 2 groups: group I (N = 20) - high response to cardiac resynchronization therapy (CRT) and group II (N = 20) - lack of response to CRT. Criteria of CRT efficacy were: decrease in end-systolic left ventricular volume equal to or more than 15 %, relative increase in left ventricular ejection fraction equal to or greater than 10 %, decrease in functional class of chronic heart failure (NYHA) equal to 1 or greater. Low response of CRT was determined as the absence of criteria said above (the lack of positive dynamics in left ventricle diameters and volumes, ejection fraction, or it had a negative value in the form of further enlargement of the heart chambers and the reduction of its contractile capacity). The initial patient separation by the degree of response to cardiac resynchronization therapy suggests verification the hypothesis that a different response to CRT may be associated with the relative position of the ventricle electrodes and the parameters of ventricular myocardial dyssynchrony.

Objective. To study possibilities of non-invasive electrophysiological mapping (NEM) in assessment of dependence of cardiac resynchronization effect from the position of the left ventricular electrode (LVE). Design and methods. NEM was performed on 24 patients, utilizing the «Amycard 01C EP LAB». Position of the stimulation LVE pole was estimated on the segmental epicardial ventricular model; and the epicenter of the late activation area of the left ventricular (LV) with complete left bundle branch block (LBBB) was determined. Also the interventricular electrode distance was measured. Results. The epicenter of the late zone on LBBB most frequently was determined in the basal area on the border of the posterior and lateral walls of the LV - 42 % (n = 10). In patients with response to cardiac resynchronization therapy (CRT) the distance (LVE pole - the epicenter of the epicardial late activation area of the LV on LBBB) was not significantly greater than the width of the LV segment. The smallest interventricular electrode distance of 49 mm was found in patient without response to CRT. Conclusion. Using NEM, one may accurately measure the distance between the stimulating poles of ventricular electrodes and the distance from the stimulating LVE pole to the epicenter of the epicardial late activation area of the LV on LBBB. The CRT effect is clearer if the distance between LVE and late zone is not significantly greater than the width of one LV segment.

The aim of the study was to provide comparative analysis of the zones with maximum intraventricular myocardial dyssynchrony (IVD) and the localizations of ventricular electrodes in patients with differential responses to cardiac resynchronization therapy (CRT). Materials and Methods: Retrospective study comprised patients (n=40) who had sinus rhythm, complete left bundle branch block (LBBB), left ventricular (LV) ejection fraction (EF) 15%, relative increase of LV eF ≥10%), and group 2 (n=20) with insufficient response to CRT (the absence of dynamics in the sizes, volumes, and LV EF). For topical evaluation of the zone of stimulation with ventricular electrode, a vector analysis of ECG was performed in the beginning and the end of the follow up period (VL was divided in 12 segments, RV was divided in 3 segments). Intraventricular and interventricular dyssynchrony of the myocardium was detected by echocardiography with tissue Doppler sonography. Results: initially, the groups did not differ in regard to gender, age, and parameters of echocardiography with tissue Doppler sonography. The absence of initial IVD was observed in 7 patients of group 1 and in 8 patients of group 2, p = 0.503, cardiomyopathy of ischemic genesis significantly prevailed in group 2 (75%, n=15, р=0.014). Dislocation of the leads was not documented for the entire period of the study, displacement of LV electrodes within the vein of the coronary sinus occurred in three cases. The final sizes, volumes, and LV EF values differed between the groups (р < 0.001), mean LV EF was 44.9±5.9% in group 1 and 26.9±6.4% in group 2. Overlapping of maximum IVD zone with the site of LV electrode implantation was more significant in group 1, р = 0.028. Final values of IVD were within normal ranges in both groups, the absence of IVD was observed in 95% and 80% of patients in group 1 and group 2, respectively, р = 0.493. Conclusions: correspondence of the myocardial zone with maximum dyssynchrony to the site of the Lv lead implantation was associated with a high response to CRT in the long term. Insufficient response can be caused by a non-optimal positioning of the LV electrode, lack of agreement between implantation site and IVD zone, and by positions of the ventricular electrodes close to each other.

Electrocardiography (ECG) is one of the main methods of cardiovascular diagnosis, its principle consists of graphically reflected electrical signals from the myocardium. The currently used standard electrocardiogram leads reflect changes in the excitation processes of myocardium in both time and space - in the frontal and horizontal axes. Direction of the excitation wave can be conventionally represented as a total vector which reflects the running of electrical impulses in the heart. Cardiac resynchronization therapy (CRT) with biventricular pacing is aimed to synchronize the timing of right and left ventricle. Response to CRT depends on the site of ventricular leads implantation and their relative position, which can be determined by using ECG vector analysis. The aim of this study: to give a descriptive assessment of the ECG patterns in isolated left/right ventricular stimulation at various electrode positions using the standard X-ray projections in CRT patients.

Цель исследования: дать сравнительную оценку зон максимальной внутрижелудочковой диссинхронии (ВЖД) миокарда и локализации желудочковых электродов у пациентов с различным ответом на сердечную ресинхрони зирующую терапию (СРТ). Материал и методы. Ретроспективное исследование, включающее пациентов (n=40) с синусовым ритмом, полной блокадой левой ножки пучка Гиса (ПБЛНПГ), фракцией выброса левого желудочка (ФВ) ≤35%, III и IV функциональным классом (ФК, NYHA) хронической сердечной недостаточности (ХСН) на оптимальной медикаментозной терапии, которым была имплантирована система СРТ. Под рентгеноскопическим контролем правопредсердный (ПП) электрод имплантировался в ушко ПП, правожелудочковый (ПЖ) электрод – в область межжелудочковой перегородки (МЖП) или верхушку ПЖ, ЛЖ электрод – в одну из вен коронарного синуса. Средний возраст составил 60,9±11,4 лет, 65% мужчин (n=26), 35% женщин (n=14), ишемический генез кардиомиопатии (КМП) был выявлен в 52,5% случаев. Период наблюдения после имплантации СРТ составил 12,0±1,7 мес. Пациенты были разделены на группы: 1 я группа, n=20 – высокий ответ на СРТ (уменьшение конечно систо лического объема ЛЖ – КСО ≥15%, относительный прирост ФВ ЛЖ ≥10%); 2 я группа, n=20 – недостаточный ответ на СРТ (отсутствие динамики размеров, объемов, ФВ ЛЖ). Для топической оценки зоны стимуляции желу дочковых электродов использовался векторный анализ ЭКГ в начале и в конце периода наблюдения (разделение ЛЖ на 12 условных сегментов, ПЖ – на 3 сегмента). Межжелудочковая (МЖД) и внутрижелудочковая диссинхро ния миокарда определялись при помощи эхокардиографии (ЭхоКГ) с тканевой допплерографией. Результаты. Исходно группы не различались по полу, возрасту и параметрам ЭхоКГ с тканевой допплерографией. Отсутствие исходной ВЖД наблюдалось у 7 пациентов 1 й группы и 8 пациентов 2 й группы, р=0,503; КМП ишемического генеза значимо превалировала во 2 й группе (75%, n=15, р=0,014). Дислокаций электродов за весь период наблю дения выявлено не было; имело место смещение ЛЖ электрода в пределах вены коронарного синуса в 3 случаях. Конечные размеры, объемы и ФВ ЛЖ между группами были различны (р<0,001); средняя ФВ ЛЖ 1 й группы со ставила 44,9±5,9%, 2 й группы – 26,9±6,4%. Совпадение зоны максимальной ВЖД с местом имплантации ЛЖ элек трода было больше в 1 й группе, р=0,028. Конечные значения МЖД были в пределах нормы в обеих группах наблюдения, отсутствие ВЖД наблюдалось в 95% 1 й группы, 80% – 2 й группы, р=0,493. Выводы: совпадение зоны максимальной диссинхронии миокарда с местом имплантации ЛЖ электрода ассоциировано с высоким ответом на СРТ в отдаленные сроки наблюдения. Недостаточный ответ может быть обусловлен неоптимальной позицией ЛЖ электрода – несовпадением места имплантации с зоной ВЖД, а также расположением желудочковых электро дов вблизи друг друга. Ключевые слова: сердечная ресинхронизирующая терапия, диссинхрония миокарда, анализ ЭКГ.

To analyze anatomical mapping techniques and explore potentialities of non-invasive surface epi- and endocardial mapping in the diagnosis of complete left ventricular myocardial dyssynchrony, 41 patients with complete left bundle branch block were examined.

To reveal predictors of response to cardiac resynchronization therapy (CRT) by comparing zones of maximal intraventricular dyssynchrony (IVD) and location of ventricular electrodes (VE), the retrospective study included 40 patients, including 26 men (65%) and 14 women (35%), with the sinus rhythm and implanted CRT system according to the commonly accepted indications. The patients aged 60.91±11.43 years; ischemic cardiomyopathy was documented in 48% of cases according to the data of coronary angiography and/or the documented evidence of myocardial infarction. Patients with significant valvular disease (more than moderate valvular regurgitation or any valvular stenosis) as well as more than mild pulmonary hypertension were excluded from the study. The study subjects were distributed into two groups. Group I (n=20) included subjects with a pronounced response to CRT. The CRT response criteria were as follows: decrease in the left ventricular (LV) end-systolic volume (ESV) by at least 15%, a relative increase in the LV ejection fraction (EF) by at least 10%, improvement of the chronic heart failure (CHF) by at least 1 functional class. Group II (n=20) included patients with an inadequate response to CRT (no positive changes in size, dimensions, and EF LV). While implanting the CRT system, the right atrial (RA) electrode was positioned at the right auricle; the right ventricular (RV) electrode was positioned at basal or medial parts of the inter-ventricular septum (IVS) or the RV apex. The LV electrode was implanted into any branch of the coronary sinus. The follow-up period lasted for 12.0±1.7 months. Coincidence of the zone of maximal IVD with the site of the LV electrode implantation was assessed with the aid of the vector ECG analysis in 12 standard leads during the isolated LV pacing using 12 conventional segments, as follows: 3 posterior segments, 3 posterolateral ones, 3 lateral ones, and 3 anterolateral ones on the basal, medial, and apical levels. The RV electrode location was assessed during the isolated RV pacing using 3 following conventional segments: basal part of IVS., medial part of IVS., and apex of RV. After 12 months of follow-up, considerable difference between the study groups in the end diameters, volume, and LV EF was shown (p<0.001). LV EF was 44.9±5.9% in Group I, 26.9±6.4% in Group II. A better functional class of CHF was found in Group I than in Group II (15 and 6 of patients with CHF II (NYHA), respectively, p=0.043). No IVD after 12 months of follow-up was observed in 19 patients of Group I and 16 patients of Group II, p=0.493. It should also be noted that in patients with IVD at baseline (13 subjects of Group I and 12 subjects of Group II), in 12 months IVD was detected in 1 patient of Group I and 4 patients of Group II. Thus, IVD recovered in 91.7% of cases in Group I and in 66.7% of cases in Group II, p=0.068. According to the ECG data, coincidence of the zone of maximal IVD with the site of the LV electrode implantation was more frequent in Group I (13 patients) than in Group II (6 patients), p=0.028. Thus, CRT is a complex process which includes the correct selection of patients, the device implantation itself, as well as subsequent long-term follow-up with the CRT parameter correction and medical therapy. IVD at baseline, coincidence of the zone of maximal IVD with the site of the LV electrode implantation and the distance between ventricular electrodes can be considered predictors of a better outcome in CRT to be taken into consideration during implantation. Coincidence of the zone of maximal IVD with the site of the LV electrode implantation in associated with a substantial long-term improvement in the hemodynamics of subjects with CRT.

To assess late effects of the inter-ventricular delay optimization calculated on the basis of the QRS complex width change on the indices of intracardiac hemodynamics in patients with cardiac resynchronization therapy, 60 patients were examined.