Persistent left superior vena cava in a patient with an implanted dual-chamber pacing system in atrial fibrillation with tachycardia-bradycardia syndrome.

The relevance of the study is conditioned by the problem of implantation of an artificial cardiac pacemaker in atrial fibrillation in patients with tachy-brady syndrome according to the standard scheme related to the presence of a congenital anomaly, such as persistent left superior vena cava. The purpose of the study is to develop an operative method of implantation of a permanent two-chamber pacemaker in patients with tachy-brady syndrome with concomitant pathology of the persistent left superior vena cava. Research methods are the generally accepted clinical and instrumental examination of the patient, including taking anamnesis and a standard cardiological examination, electrocardiography, transthoracic echocardiography, plain radiography, angiocardiographic examination, and multispiral computed tomography, which, along with a general analysis, confirm the presence of tachy-brady syndrome with atrial fibrillation and congenital anomaly in the form of persistent left superior vena cava in patients. The study presents a developed model of surgical implantation of a permanent two-chamber pacemaker to stabilise the condition of patients with atrial fibrillation related to tachy-brady syndrome with concomitant persistent left superior vena cava; the standard implantation mechanism included the introduction of a radiopaque agent to clarify the anatomical structure of the vascular bed, further, its entry from the subclavian veins into the persistent left superior vena cava and into the cavity of the right atrium through the venous coronary sinus was detected, and then a gradual introduction of an endocardial right ventricular electrode was performed into the subclavian vein through the tricuspid valve along with its further positioning in the apex of the right ventricle; therefore, a permanent two-chamber pacemaker can be successfully installed, creating conditions for restoring sinus rhythm in this group of patients, which is of practical importance for the field of medicine (Tab. 3, Fig. 4, Ref. 20). Keywords: atrial fibrillation, persistent left superior vena cava, sick sinus syndrome, pacemaker implantation, cardiac surgery.

Atrial fibrillation: Epidemiology, pathophysiology, and clinical complications (literature review).

The last three decades have been characterized by an exponential increase in knowledge and advances in the clinical management of atrial fibrillation. The purpose of the study is to provide an overview of the pathogenesis of nonvalvular atrial fibrillation and a comprehensive investigation of the epidemiological data associated with various risk factors for atrial fibrillation. The leading research methods are analysis and synthesis, comparison, observation, induction and deduction, and grouping method. Research has shown that old age, male gender, and European descent are important risk factors for developing atrial fibrillation. Other modifiable risk factors include a sedentary lifestyle, smoking, obesity, diabetes mellitus, obstructive sleep apnea, and high blood pressure predisposing to atrial fibrillation, and each has been shown to induce structural and electrical atrial remodeling. Both heart failure and myocardial infarction increase the risk of developing atrial fibrillation and vice versa creating feedback that increases mortality. The review is a comprehensive study of the epidemiological data linking nonmodifiable and modifiable risk factors for atrial fibrillation, and the pathophysiological data supporting the relationship between each risk factor and the occurrence of atrial fibrillation. This may be necessary for the practice of the treatment of the cardiac system.

Comparative Effectiveness and Safety of Cryoablation Versus Radiofrequency Ablation Treatments for Persistent Atrial Fibrillation.

The purpose of this study was to compare the effectiveness and safety of 2 strategies for catheter treatment of patients with persistent atrial fibrillation in the long-term period, using cardiac implantable loop recorders. The research is a prospective, randomized, controlled study designed to compare the results of modern catheter technologies in patients with persistent atrial fibrillation. The study included 127 patients with persistent atrial fibrillation in the last 6 months before inclusion in the study, for whom at least 2 antiarrhythmic drugs of class I to III were not effective. By random distribution, 50 patients were included in group 1; they underwent cryoballoon ablation, using a cryoballoon of the second generation. Group 2 also included 50 patients who underwent radiofrequency ablation, where a catheter was used to control the contact force. Cardiac implantable loop electrocardiogram recorders were implanted in all patients after surgery. The average duration of follow-up was 36 months. The primary end point of efficacy occurred in 15 patients in the group with cryoballoon ablation and 14 patients in the group with radiofrequency ablation. In conclusion, the primary effectiveness was relatively the same in the groups; yet, in the long-term period, the superiority of radiofrequency ablation using catheters with pressure control was noted, but the difference in results was statistically insignificant (p <0.672) and there was no significant difference between the 2 methods in terms of overall safety.

Efficacy and Safety Results of Different Ablation Technologies for Persistent Atrial Fibrillation Treatment.

INTRODUCTION: Pulmonary vein isolation is the primary goal in treating patients with paroxysmal atrial fibrillation using catheter ablation. This study's purpose is a comparative assessment of the efficacy and safety of two strategies for catheter treatment in patients with persistent atrial fibrillation. PATIENTS AND METHODS: The study included 127 patients with persistent atrial fibrillation during the last six months before inclusion in the study. The average follow-up period was 24 months. RESULTS: The primary efficacy endpoint (death, cerebrovascular event, or serious complications associated with treatment) occurred in 15 patients in the cryoballoon ablation group and 14 patients in the radiofrequency ablation group. The Kaplan-Meier survival estimates were 30% and 28%, and the risk ratio   0.96 and 95% of the confidence interval. CONCLUSIONS: The treatment in patients with persistent atria fibrillation, using catheter ablation with contact force control catheter treatment with the pulmonary vein isolation, was more efficient.

The efficacy and safety of cryoballoon catheter ablation in patients with paroxysmal atrial fibrillation.

BACKGROUND: Electrical isolation of pulmonary vein ostia is an established therapy for paroxysmal atrial fibrillation. AIMS: The purpose of this study is to evaluate the long-term efficacy and safety of cryoballoon catheter ablation in paroxysmal atrial fibrillation with normal anatomy of the left atrium. METHODS: Two hundred fifteen consecutive patients were included in the study (from November 2014 to November 2016). All the patients had symptoms of paroxysmal atrial fibrillation resistant to antiarrhythmic drugs and underwent pulmonary vein cryoisolation using second-generation cryoballoons. Standard "single-shot" cryoballoon exposures were used alternately for each of the four pulmonary veins. The endpoint of the ablation procedure was the electrical isolation of each pulmonary vein. RESULTS: Sixty-nine patients had stable atrial fibrillation recurrences and left atrial flutter with 30 of 69 patients having atrial fibrillation paroxysms during the first year after primary ablation. Repeated ablation was performed within 6-12 months after the first ablation. In 39 of 69 cases, arrhythmia recurrences were registered during the second and third year after the first ablation. These patients underwent repeated ablation within 12-36 months after the first ablation. In 98% of the patients, no disease progression with a transition to a persistent form of atrial fibrillation was observed. During the mean 5-year follow-up period, no disease progression with the transition to persistent forms of atrial fibrillation was observed. CONCLUSIONS: It was concluded that in patients with paroxysmal atrial fibrillation, with normal left atrium anatomy and no risk factors, it can be controlled with single pulmonary vein isolation without additional atrial substrate modification.

Prediction of arrhythmia recurrence after atrial fibrillation ablation in patients with normal anatomy of the left atrium.

BACKGROUND: Enlarged left atrium is an established predictor of atrial fibrillation recurrence after pulmonary vein isolation but arrhythmia recurrence is also observed in patients with normal anatomy of the left atrium. The aim of the study is to evaluate arrhythmia recurrence predictors in patients with normal anatomy of the left atrium. METHODS: The study included 182 patients with normal anatomy of the left atrium who underwent pulmonary vein isolation using catheter ablation. Various parameters were also compared, including age, gender, history of arrhythmia, arterial hypertension, concomitant coronary pathology, echocardiography findings, such as mitral valve and tricuspid valve regurgitation and procedure parameters, between patients with and without relapses. Statistical analysis was performed using the IBM SPSS Statistics-19 software. RESULTS: Transthoracic echocardiography was performed by independent specialists with extensive experience. Trans-esophageal echocardiography was performed before each ablation procedure. Standard trans-septal puncture was performed under fluoroscopic control. Radiofrequency ablation was performed in the ipsilateral pulmonary vein antrum with a wide capture of nearby lung tissue. CONCLUSIONS: It was concluded that the tricuspid valve regurgitation and arterial hypertension correlate with atrial fibrillation recurrence after pulmonary vein isolation in patients with normal left atrial anatomy.