Valery A. Sakovich

Aim. To identify predictors of heart failure in patients with dilated cardiomyopathy (DCM) and ischemic myocardial dilatation (IMD).Material and methods. In total, we examined 221 patients with cardiomyopathies: DCM and IMD. The mean age of the patients was 55,30±9,69 years (minimum — 20 years, maximum — 77 years). From the total number of patients, a group of patients with DCM (idiopathic origin) (group 1) was identified in the amount of 111 people, of which 99 were men (89,2%) and 12 women (10,8%). The mean age of patients with DCM was 51,73±9,74 years, for men — 51,00±8,96 years, for women — 57,75±3,71 years. The median age in DCM patients was 53,00 [48,00; 58,00], for men — 53,00 [46,00; 57,00], in women — 59,50 [49,00; 68,75]. Patients with IMD (ischemic origin) consisted of 110 people (group 2), of which 100 were men (91,5%) and 10 women (8,5%). The mean age of patients with IMD was 58,68±8,38 years, for men — 58,29±8,46 years, for women — 62,90±6,29 years. The median age in patients with IMD was 58,00 [53,50; 63,50], in men — 58,00 [52,00; 63,00], in women — 61,50 [59,25; 66,00]. Biological material (venous blood) was taken from all patients for molecular genetic analysis. To isolate the DNA structure, the phenol-chloroform extraction was used. Using the polymerase chain reaction, genotyping of gene polymorphisms was carried out, followed by analysis of restriction fragment length polymorphisms.Results. To assess the left ventricular systolic function, the ejection fraction was assessed. Heart failure and its severity are most often associated with a decrease in left ventricular (LV) systolic function. In our study, in the group of patients with DCM, the mean LV ejection fraction (EF) was 25,105±6,76, while in IMD group — 20,255±4,49 (p=0,0001). This confirms that these two groups have severe heart failure associated with impaired LV systolic function — a decrease in EF MMP3 gene polymorphism compared to the control group (66,7% vs 12,5%, p=0,023).Conclusion. The heterozygous genotype of the MMP3 gene polymorphism can be considered as a predictor of the development of HF in patients with IMD for the purpose of early diagnosis and prevention of heart failure. In the group of patients with DCM, no differences were found during a comparative analysis with gene polymorphism.

The choice of an optimal, most safe and physiological place in the heart for the electrode implantation is an issue to be solved by a specialist in surgery of heart arrhythmias. According to the literature, the techniques to stimulate both cardiac apex and other alternative areas are imperfect. At present, stimulation of the heart conduction system, namely, the His bundle is considered a promising area in arrhythmology. This type of stimulation is a physiological one, while it involves the His-Purkinje system. We present a successful clinical case of the electrode implantation with a two-chamber pacemaker to the heart conduction system in a 67-year-old patient with permanent atrial fibrillation. The surgical intervention made it possible to reduce the QRS length from 180 to 110 ms. This clinical case shows that the heart conduction system pacing allows for implementation of the principles of physiological stimulation in patients with impaired atrioventricular conduction. The technique with a two-chamber pacemaker is feasible in clinical practice.

Premature ventricular contractions (PVC) is a very common type of arrhythmia. Some patients require surgical treatment. The search for the safest methods of surgical treatment is an important research task.Aim. To evaluate the efficacy and safety of catheter ablation in patients with idiopathic ventricular arrhythmias depending on the implementation of X-ray control.Material and methods. The study included 183 patients admitted to the Federal Center for Cardiovascular Surgery for elective surgery, with frequent idiopathic PVC and indications for surgical treatment of arrhythmia. In the majority of patients with idiopathic PVC, the central origin of ectopia is the right ventricular outflow tract (RVOT). The patients were divided into two groups: group 1 (n=90) — patients with idiopathic PVC after fluoroscopy-guided radiofrequency ablation (RFA); group 2 (n=93) — patients after RFA without fluoroscopy. All patients underwent electrocardiography, echocardiography, and electrophysiological testing. All patients before and after RFA underwent 24-hour Holter monitoring.Results. Among patients of group 1, the initial success of RFA was 62,2%, and in group 2 — 71% (p=0,21). Surgery complications were registered in 3,3% and 4,3% of patients of groups 1 and 2. No deaths have been reported. The duration of surgery did not depend on the use of fluoroscopy. Among patients with failed initial RFA, the effectiveness of subsequent interventions was 88,6%. The greatest efficiency of initial RFA was observed when the ectopic ventricular focus was located in RVOT The lowest efficiency of RFA was observed when the focus was located in the left ventricular papillary muscles.Conclusion. RFA in patients with idiopathic PVC without fluoroscopy does not increase the complication rate and the duration of surgery and have a comparable efficacy compared to fluoroscopy-guided RFA.