Aims. Analysis of the prevalence of clinical events and of the trends of the physiologically significant parameters in patients with cardiac implantable electronic devices (CIEDs) with the remote monitoring options.

Methods. In 9 clinical centers of the Russian Federation and 2 clinical centers of the Republic of Kazakhstan, 126 patients with an ICD or a pacemaker provided with the Home Monitoring technology (BIOTRONIK, Berlin, Germany) have been enrolled into the ReHoming (Registry Home Monitoring) clinical study. Based on the daily data transmission, all alarm alerts and all the Home Monitoring options changes have been registered with dated alert content and undertaken measures.

Results. The study patients, followed up at least for one year, demonstrated 42 adverse events (AE), 26 of which were serious AE (SAE) and 3 SAE were defined as device related (SADE). ICD patients (n=90) had statistically significantly higher SAE prevalence with attendant coronary artery disease (CAD) (p=0.0249). Patients with CRT/D compared to patients with dual-chamber or single-chamber ICD had less SAE rate (р=0.046). Downloads of Home Monitoring parameters for retrospective mathematical analysis were available for 60 ICD patients, 47 of which had episodes of ventricular tachycardia (VT), ventricular fibrillation (VF) and/or atrial tachyarrhythmia (AT). Machine learning analysis of the trends of the physiologically meaningful parameters revealed correlation of the changes with arrhythmia episodes, the random forest method and the gradient boosting method giving the results strongly exceeding a random guess.

Conclusion. Home Monitoring of CIED patients enables evaluation of clinical advantages of different device types application, also in regard to prevention of adverse events and possible iatrogenic effects of electrotherapy of the heart. The study results demonstrate a possibility to develop a predictor of arrhythmia episodes, based on daily transmission of trends of physiologically meaningful Home Monitoring parameters.

Aim: to assess cardiac conduction disturbances after transcatheter aortic valve replacement (TAVR) with the “MedLab-KT” device in early postoperative period.

Methods. The study comprised 80 patients (mean age 72,4±5,1 years; 42,5% males) undergoing successful TAVR with the “MedLab-KT”. Before operation, all patients were evaluated with 12-lead ECG and 24-hour Holter monitoring, transthoracic and transesophageal echocardiography, computed tomography, coronarography. In 29 (36,3%) patients cardiac conduction abnormalities were detected before operation: 1st degree atrioventricular (AV) block was found in 17 patients, including concomitant left anterior hemiblock (LAH) in 7 patients, and right bundle branch block (RBBB) in 3 (LAH+RBBB). Second degree AV-block type 1 was found in 1 patient. LAH – in 2, RBBB – in 5, and left bundle branch block (LBBB) – in 4. Post-operative follow-up was limited to hospital stay (13,4±7,4 days).

Results. De-novo conduction abnormalities (reversible and irreversible) were detected in 41 patients (51,3%). Post-TAVR complete AV-block was found in 6 (7,5%) patients, and required temporal pacing. In 4 of those patients AV-block was transient and resolved within 1 day. In 2 (2,5%) patients permanent pacing was required due to irreversible distal AV-block. In one case AV-block developed 2 days after TAVR in a patient with pre-existent 1st degree AV-block in combination with LAH+RBBB. Another patient developed complete AV-block at 3d day after TAVR; in this case there was pre-existent 1st degree AV-block plus LAH. Persistent interventricular block was found in 35 patients: complete LBBB - in 17 patients and complete RBBB – in 1 patient. There were no statistically significant predictors of conduction disturbance development following TAVR.

Invasive electroanatomical mapping of polymorphic and unstable ventricular arrhythmias is a complex and laborious task. Noninvasive epi-endocardial ElectroCardioGraphic Imaging (ECGI) is a novel beat-to-beat mapping technique. The present work is a second part of single-center single-blind cross-sectional study to verify epi-endocardial ECGI accuracy. This part is particularly dedicated to investigate ECGI accuracy during right ventricular endocardial pacing followed by polygon model quality assessment and detailed analysis of cumulative effect of many different factors.

Methods. 37 patients with previously implanted pacemakers were enrolled in the study. All patients underwent epiendocardial ECGI mapping (Amycard 01C EP Lab, Amycard LLC, Russia - EP Solutions SA, Switzerland) during right endocardial ventricular pacing. The data obtained from torso and ECG-gated cardiac computed tomography (Somatom Definition 128, Siemens AG, Germany) were used to create three-dimensional ventricular models. Geodesic distance between noninvasively reconstructed early activate zone on the isopotential maps and RV reference pacing site were measured to evaluate ECGI accuracy for each patient.

Results. The mean (SD) geodesic distance between noninvasively reconstructed and reference pacing site was 23 (14) mm for RV epicardial models and 9 (12) for RV endocardial surface of epi-endocardial models, median (25-75% IQR) - 21 (11-32) мм and 4 (2-8) mm respectively. ECGI accuracy on RV endocardial surface of epi-endocardial models was significantly better than on epicardial models (p <0,001). At the same time, there were no significant associations between cardiac CT, pacing parameters, clinical characteristics and accuracy values.

Conclusions. The main results showed a possibility of novel epi-endocardial ECGI mapping to detect RV focal arrhythmias with high accuracy (median 3 mm) and to recognize endocardial localization with high percent of probability (more than 94%) comparable with invasive electroanatomical mapping. Therefore, this study confirms sufficient accuracy of epi-endocardial ECGI mapping technology for non-invasive topical diagnosis of RV focal arrhythmias.

The operation of coronary shunting in patients with coronary heart disease leads to the development of various complications in the postoperative period, the most frequent are heart rhythm disturbances.

Purpose. To establish the connection of intraoperative hemolysis (IOH) with the development of cardiac rhythm disturbances in patients with coronary artery disease after coronary shunting in con-ditions of cardiopulmonary bypass (CB).

Material and research methods. The assessment of the degree of IOH was made by the level of free hemoglobin [Hb] In the blood plasma at the beginning of the operation, immediately after the patient was connected to the CB device and 15 minutes before removal from the CB, using the HemoCue Plasma / Low Hb analyzer. According to the degree of IOH, patients (n = 123) are divided into 3 groups (gr.) in accordance with free [Hb]: gr.1 - ≤0,1 g/l; gr.2 - > 0.1 g/l and <0,5 g/l; gr.3 - ≥0,5g/l. Were used the following instrumental methods of investigation: electrocardiography, 24-hour ECG mon itoring. Was analyzed the frequency of heart rhythm disturbances in patients after coronary shunting with various levels of IOH in the perioperative (during the operation and during the first days after it) and in the early (up to 1 month) periods.

Results. Arrhythmias were observed in 2.3% of patients of the 1st group, in 11.9% - the 2nd group, in 52.6% - the 3rd group. Associations were noted between [Hb]. In plasma at the end of cardio-pulmonary bypass and the frequency of arrhythmias (rs=0,70, p<0.001). The share of life-threatening and hemodynamically significant arrhythmias in the study period in the group with a high degree of IOH accounted for about half of all arrhythmias that occur, which is significantly more than in the group without IOH and with low IOH, p <0.001.

Conclusion. The operation of coronary artery bypass surgery in conditions of artificial blood circu-lation leads to the development of arrhythmias in the postoperative period in 22% of patients with ischemic heart disease. A significant proportion of these are arrhythmias that pose a threat to the pa-tient’s life and arrhythmias, causing hemodynamic disturbances and hypoperfusion of vital organs. The largest number of patients with cardiac rhythm disturbances after coronary artery bypass graft-ing was observed in the group with the level of free hemoglobin in the blood plasma of 0.5 g/l or more (p <0.001), which indicates the relationship between the occurrence of arrhythmias and the degree of intraoperative hemolysis. The high risk of arrhythmias in patients with coronary heart dis-ease after coronary artery bypass surgery is determined when the content of free hemoglobin is more than 0.85 g/l. One of the ways to assess the risk of heart rhythm disturbances should be to determine the level of free hemoglobin in the blood plasma of patients in the intraoperative period of coronary artery by-pass grafting, which is necessary for the timely prevention and correction of possible hemodynamic disorders.

Aims. To assess the outcomes of atrial fibrillation (AF) treatment by radiofrequency ablation for patients with mitral valve replacement, the analysis of short-term results of 128 patients was performed.

Methods. Mean age of the patients was 56,7±9,6 (29 - 79) years, males - 39, females - 89. Most of the patients had longstanding persistent AF - 81 (63,3%), 28 (21,9%) had persistent AF and 19 (14,8%) - paroxysmal AF. The indications for surgery were: rheumatic mitral valve disease in 105 patients (82%), degerative mitral valve disease - in 21 (16,4%) and with treated infectious endocarditis - in 2 (1,6%). Maze IV procedure was carried out in all cases.

Results. Hospital mortality was 0,8% (1 patient). Ten patients (7,9%) required pacemaker implantation. The indications were sinus node dysfunction in 7 patients, bradycardia AF - in 2 patients, AV node dysfunction - in 1. At the discharge 88 patients (69,3%) had a sinus rhythm, 10 (7,9%) - atrial rhythm, pacemaker rhythm with sinus node dysfunction patients - in 4 (3,1%) and AF - in 25 (19,7%). Thus, the rate of freedom from atrial fibrillation was 80,3% (102 patients). The effectiveness of ablation for paroxysmal AF was 100%, persistent - 74,1%, longstanding persistent - 77,8% (p=0,006). To reveal other predictors of freedom from AF at the discharge each ECHO parameter was included in the simple logistic regression analysis. Statistically significant p-value was obtained for the preoperative right atrial size (p=0,005), and close to it for the left atrial size, especially for the index left atrial volume/body surface area (p=0,052).

Conclusion. Thus, the radiofrequency ablation is an effective method for treatment of AF in patients undergoing mitral valve replacement. The rate of freedom from AF at the discharge is 80,3%. The predictors of freedom from AF at the discharge are preoperative form of AF and preoperative size of atria.

Aim: assessment of the capabilities of “machine learning” methods in predicting remote outcomes in patients with non-valvular atrial fibrillation (AF).

Methods. From 2015 to 2016 234 patients with non-valvular AF were included in the study (median age 72 (65; 79) years; 50.0% men). During the median follow-up of 2.9 (2.7; 3.2) years 42 patients died, 9 patients had non-fatal acute cerebral circulatory disorders and 3 patients had non-fatal myocardial infarction (MI). These events in 52 subjects (22.2% from all patients included) were combined into a combined endpoint (death and a nonfatal cardiovascular accident at the stage of remote observation). The first 184 patients comprised a “training” group. The next 50 patients formed the “test” group. The following methods of «machine learning» were used in the analysis: classification trees, linear discriminant analysis, the k-nearest neighbor method, support vectors method, neural network.

Results. Long-term outcomes were influenced by age, known traditional risk factors for cardiovascular diseases, the presence of these diseases, changes in intracardiac hemodynamics and heart chambers as evaluated by echocardiography, the presence of concomitant anemia, advanced stages of chronic kidney disease, and the administration of drugs associated with a more severe cardiovascular disease progression (amiodarone, digoxin). The best prognosis was created using the model of linear discriminant analysis, the complex neural network model, and the support vector machine.

Conclusion. Modern methods aimed at prognosis estimation seem to be of great potential for cardiology. These methods include big data analysis and machine learning technologies. The methods require further evaluation and con firmation, and in the future they may allow correcting cardiovascular risks, using data from real clinical practice and evidence-based medicine at the same time.

Prof. Sergey V. Popov - 60 Years!

VIII All-Russian Congress of Arrhythmologists.