Aim. To determine the clinical, instrumental and laboratory factors associated with the development of new-earlypostoperative atrial fibrillation (POAF) in patients after non-cardial surgical interventions. Methods. Cohort retrospective study: 226 case histories were selected from the archive, of which 70 patients were diagnosed with POAF for the first time after non-cardial surgical interventions and 156 patients without it. Results.Patients in the POAF group were statistically significantly older than patients without POAF: the average age was 77 (69;84) years versus 61 (44;71) years (p<0.001), respectively. In addition, patients with POAF were more likely to have a history of myocardial infarction: 30% vs. 8.4% in the group without POAF (p<0.001); more often had a history of cardiac arrhythmias: 35.7% vs. 10.3% with POAF (p<0.001). Thromboembolic complications and pneumonia were more common in the POAF group: 35.7% and 51.4% versus 3.9% and 11%, respectively (p<0.001). There were no differences between the groups in the urgency of surgical intervention. There were also no differences in the volume of postoperative infusion of solutions (p>0.05), the frequency of bleeding after surgery (p=0.290) and the duration of hospitalization (p=0.613).When constructing the logistic regression, it was found that statistically significant independent predictors of POAF development were: myocardial infarction (OR 4.7 at 95% CI 2.2-10.1), history of cardiac arrhythmias (OR 5.0 at 95% CI 2.5-10.3), CHF 2-3 FC (OR 9.9 at 95% CI 5.2-19.1), diabetes mellitus (OR 4.0 at 95% CI 2-8), COPD (OR 8.6 at 95% CI 1.7-42.3), intraoperative infusion of more than 3 liters (OR 3.4 at 95% CI 1.6-7.4). Conclusions.Patients who developed POAF after abdominal surgery are significantly older than patients without POAF, have more pronounced concomitant pathology: they often have a history of myocardial infarction and cardiac arrhythmias, more often suffer from severe chronic heart failure, diabetes mellitus and chronic obstructive pulmonary disease. The development of atrial POAF is more often noted with a large infusion of solutions during surgery, as well as with repeated laparotomies. In the early postoperative period, systemic inflammatory reaction syndrome and thromboembolic complications are more common in patients with POAF.

Background.Cardiac arrhythmias remain a clinically significant problem in the conditions of the general surgical department, since they make a significant contribution to the risk of fatal complications. The aim of the study. To study the clinical, instrumental and laboratory characteristics of patients depending on the development or absence of a fatal outcome after non-cardial abdominal surgical interventions, as well as to evaluate the effect of early atrial fibrillation on mortality. Methods. The methodology was carried out according to the type of "case-control" study. 83 lethal "cases" were selected and 143 "controls" were selected. A total of 226 medical histories are included in the analysis. Results.The group with mortality was significantly older than the group without mortality: 75 (64;82) years versus 61 (44;72) years, respectively (p<0.001). Differences in the groups were observed in the severity of concomitant pathology: in the group with mortality, CHF was significantly more pronounced (p<0.001), diabetes mellitus was more common – 34% vs. 10% (p<0.001) and the frequency of COPD was higher – 8.4% vs. 1.4% (p=0.031). However, there were no statistically significant differences in the frequency of myocardial infarction (p=0.121). Statistically significant differences in perioperative parameters included differences in intraoperative infusion of solutions with a volume of more than 3 liters (p=0.003) and in postoperative infusion of solutions with a volume of 1-3 liters and 3-5 liters (p=0.001 and p<0.001). In the group with a fatal outcome, infusion in large volumes significantly prevailed. Also, the group with a fatal outcome was statistically significantly different in the frequency of relaporotomies (p<0.001).; by the frequency of systemic inflammatory reaction syndrome (p<0.001), by the frequency of bleeding (p=0.031), by the frequency of AFP (p<0.001), thromboembolic complications (p<0.001) and the frequency of pneumonia (p<0.001). All of the above events were more often observed in the group of patients with a fatal outcome. Statistically significant independent factors increasing the risk of mortality in our sample were: history of cardiac arrhythmias (OR 3.4 at 95% CI 1.7-6.9), CHF 2-3 FC (OR 6.8 at 95% CI 3.7-12.6), DM (OR 4.9 at 95% CI 2.3-9.6), COPD (OR 6.5 at 95% CI 1.3-32), intraoperative infusion of more than 3 liters (OR 2.9 at 95% CI 1.46-5.7), postoperative infusion of 3-5 liters (OR 2.9 at 95% CI 1.6-5.0), thromboembolic complications (OR 37.9 at 95% CI 8.7-164). Conclusions.Statistically significant independent factors that increase the risk of mortality are: a history of cardiac arrhythmias, heart failure, chronic obstructive pulmonary disease, large infusion of solutions during and after surgery, diabetes mellitus, the development of thromboembolic complications. The development of postoperative atrial fibrillation increases the chances of a fatal outcome by 15 times: the odds ratio was 14.8 with 95% CI from 7.4 to 29.4.

The work aims to carry out a comparative analysis of the spectral indices of the photoplethysmogram signals and RR-intervals of healthy volunteers, patients with COVID-19, as well as patients with COVID-19 and chronic arterial hypertension of 1-2 degrees. The study included 45 records of pairs of electrocardiogram and photoplethysmogram signals. Each sample included 15 pairs of 20-minute experimental signals. The study revealed an increase in the integrated power of the low-frequency (LF) band over the integrated power of the high-frequency (HF) band in the photoplethysmogram signals in patients with COVID-19, burdened with hypertension. In the signals of the RR-intervals, the largest values of the ratio of the LF to HF indices are associated with patients without cardiovascular diseases. In turn, this may be an indicator of the different effects of viral infection and arterial hypertension on the loops of autonomic control of heart rate and vascular tone.

This study examines missing value imputation in the Russian Acute Coronary Syndrome Registry (RusACSR) and assessment of the probability of predicting mortality. Linear methods with the most probable or average value were used for imputation. The prediction problem was solved using the k-nearest neighbors method. This work reveals that the imputation method, despite their simplicity, increases the probability of prediction of mortality by 6%.

Background: The most common reason for sudden cardiac death in heart failure is malign ventricular arrhythmias. LCZ 696 improves hospitalization and sudden cardiac death outcomes in heart failure, however mechanisms in preventing sudden cardiac death are still unknown. There is little information available assessing effect of LCZ 696 on Tp-e interval and related calculations. In this study, we aimed to investigate the impact of Sacubitril/valsartan therapy on Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in heart failure patients and its reflections on clinical arrhythmogenesis. Methods: The study was designed as a prospective observational fashion. 265 patients with implantable cardioverter-defibrillator (ICD), who were on regular follow up at Samsun Training and Research Hospital Outpatient Heart Failure Clinic, were validated for the study. Clinical, echocardiographic, electrocardiogram and device data before initiation and six months after dose optimizing were obtained. Results: Stroke volume, cardiac output and ejection fraction significantly improved after LCZ 696 treatment. T wave related parameters, QT and QTC intervals significantly diminished. Furthermore, there was a negative correlation between baseline Tp-e interval duration and the absolute percentile increase of stroke volume(r:-0.234, p: 0.042) and cardiac output (r: -0.240, p: 0.037). Conclusion: In our study, switching Renin-Angiotensin-Aldosterone-System inhibitor with Angiotensin receptor/neprilysin inhibitor was associated with increase in left ventricle performance and decrease of sustained ventricular arrhythmias that required ICD shocks. These positive findings were accompanied by improvements in surface electrocaridogram changes such as Tp-e and related indices.

Введение Человек на протяжении веков стремился не только приспособиться к природной среде, но и сделать ее удобной для своего существования. Мы знаем, что любая деятельность человека оказывает влияние на окружающую среду, а ухудшение состояния биосферы опасно для всех живых существ, в том числе и для человека.Одной из самых распространенных болезней сердечнососудистой системы

ВведениеПри исследовании объектов биологической природы приходится иметь дело с рядом проблем, причиной которых часто бывает их сложное, хаотическое, нестационарное поведение. Кроме этого сигналы исследуемых объектов зашумлены.

The aim of this study was to search for typical groups that differ in terms of the autonomic regulation of the cardiovascular system among patients who underwent coronary artery bypass surgery (CABG) or correction of acquired valvular heart disease. Material and Methods ― The study included 42 patients (29% of women; 62±9 years old) with CABG and 36 patients (44% of women; 54±15 years old) who underwent correction of valvular heart disease. Synchronous 15-minute electrocardiogram and photoplethysmogram (PPG) records were recorded in all patients before and after surgery. Time domain and frequency domain indices of heart rate variability (HRV) and the synchronization index of low-frequency (LF) oscillations in HRV and PPG (index S) were evaluated. Cluster analysis (k-means clustering) was used to divide the studied patients into groups. Results ― Two clusters of patients were identified in terms of cardiovascular autonomic regulation, which differed each other in a number of preoperative parameters: hematocrit, heart rate, TP, HF%, LF% and LF/HF. Conclusion ― Notable indices of cardiovascular autonomic regulation in cardiac surgery patients are not related to their clinical status, features of surgical intervention and postoperative period.