Šileikis, Vytautas

Įvadas. Senstant visuomenei, elektrokardiostimuliatorių implantacijos procedūrų kiekis kasmet auga, medicinos technologijos tobulėja ir daugėja klinikinių tyrimų, kuriuos būtina sekti bei jų įrodymais remiantis galima sumažinti tam tikrų komplikacijų riziką. Tikslas: aptarti literatūros duomenis, kuriuose aprašomi elektrokardiostimuliatorių implantacijos procedūros klinikiniai įrodymai, galintys turėti įtakos operacijos eigai, komplikacijų pasireiškimui. Metodai. Mokslinių straipsnių paieška naudojant PubMed duomenų bazę, įtraukta 20 straipsnių, kurių didžioji dalis išleisti per paskutinius 5 metus. Literatūros šaltiniuose aprašomi su elektrokardiostimuliatorių implantacijos procedūra susiję klinikiniai tyrimai. Rezultatai. Atlikus literatūros analizę, pateikiami klinikiniais tyrimais pagrįsti duomenys, galintys turėti įtakos elektrokardiostimuliatoriaus implantacijos eigai. Išvados. Sėkminga elektrinio širdies prietaiso implantacija priklauso nuo kiekvieno etapo - pasiruošimo procedūrai, kraujavimo rizikos įvertinimo, infekcijų profilaktikos, operacijos technikos, pooperacinio laikotarpio.

Background. Dual-chamber pacemaker implantation is a standard interventional treatment strategy for symptomatic sinus syndrome (SSS)or advanced atrioventricular block (AVB). It is already known that right ventricular pacing might have detrimental effects on cardiac function. However, knowledge about atrial pacing effect on left (LA) and right (RA) atria function is still lacking. Purpose. To assess the impact atrial pacing on left and right atria morphologic and functional parameters in patients after dual-chamber pacemaker implantation. Methods. We conducted a prospective study that included patients who received a dual-chamber pacemaker for an indication of AVB or SSS. A base rate of 40 bpm and no rate response in case of clear AVB indication or a base rate of 60 bpm and rate response if indication was SSS were chosen. A transthoracic echocardiography was done the next day after pacemaker implantation and after 1 and 3 months. To remove the impact of right ventricular pacing, patients with high VP percentage (>40%) were excluded from analysis. Patients were divided into two groups – group A with high AP (>50%), and group B – low AP (<50%). LA expansion fraction reflecting reservoir function, emptying- reflecting conduit, and active emptying reflecting "atrial kick" were analysed. To compare means the Mann Whitney U test, and for categorical variables – X² test were used. Results: A total of n = 78 patients underwent dual-chamber implantation and signed informed consent. Due to significant structural heart disease or reduced ejection fraction (<50%) 7 patients were excluded from further analysis. Out of those, n = 21 were excluded due to a high VP percentage. Group A consisted of n = 26 and group B of – n = 24 patients. Average AP in group A was 63,5% and 68,3% at 1 and 3months and 5,6% and 7,2% in group B respectively. The mean age (group A 74,5 SD 8,6 years vs group B 78,1 SD 8,0 years, p = 0,266),gender distribution (group A males 45,5% vs group B 48,4%, p = 0,774), and mean BMI (group A 26,4 SD 4,8 kg/m2 vs group B 29,5 SD 3,7kg/m2, p = 0,202) did not differ significantly between the two groups. The mean left ventricular end diastolic diameter (LVEDD) and indexed LVEDD were not significantly different at baseline and did not change during the follow up period. The baseline LA and RA morphometric and functional parameters presented was not different at baseline between the two groups. The change in LA and RA functional parameters presented in figures. A tendency for a lower LA expansion fraction, active emptying fraction and LA ejection fraction were observed in group A. The trend was contant during 1 and 3 month follow-up periods. RA morphometric parameters did not change significantly between the two groups. Conclusion: Impaired LA function in a higher percentage of atrial pacing is seen early after pacemaker implantation and could progress over time. Though, even longer observational period is needed.

Background: Dual-chamber pacemaker implantation is a standard interventional treatment strategy for atrioventricular block (AVB) and sick sinus syndrome (SSS). It has been proven that a high percentage of right ventricular pacing might have detrimental effects on cardiac function. However, there is a lack of data on atrial pacing effect on left (LA) and right (RA) atria function. Purpose: To assess the impact atrial pacing on left and right atria morphologic and functional parameters in patients after dual-chamber pacemaker implantation. Methods: We conducted a prospective study that included patients who received a dual-chamber pacemaker for an indication of AVB or SSS. After signing of the informed consent pacemaker was programmed for base rate of 40 bpm and no rate response in case of clear AVB indication or for base rate of 60 bpm and rate response if indication was SSS. An transthoracic echocardiography was done the next day after pacemaker implantation and after one month at follow up (FU). During the FU the atrial pacing (AP) and ventricular pacing (VP) percentage were captured. To exclude the impact of right ventricular pacing, patients with high VP percentage (>40%) were excluded from analysis. Patients were divided into two groups – group A with high AP (>50%), and group B – low AP (<50%). LA expansion fraction reflecting reservoir function, emptying – reflecting conduit, and active emptying reflecting “atrial kick” were analysed. To compare means the Mann Whitney U test, and for categorical variables – X2 test were used. Results: A total of n=100 patients underwent dual-chamber implantation and signed informed consent. Due to significant structural heart disease or reduced ejection fraction (<50%) 11 patients were excluded. Out of those, n=30 were excluded due to a high VP percentage. Group consisted of n=28 and group B of – n=31 patients. Average AP in group A was 66.2% and 5.0% in gr[...].

Introduction: The main disadvantage of fluoroscopy usage for catheter position tracking during procedure is the X-ray exposure of the patient and personnel. Exposure varies significantly due to various factors, like pathology, patient’s anatomy and weight, physician’s experience. Alternative systems for mapping catheter position are available, using either magnetic (i.e. CartoTM) or electrical fields (i.e. Ensite NavXTM), to reduce fluoroscopy time and radiation. However, fluoroscopy remains one of the most widely used method to track catheters during the procedure. [1-4] Aim: To evaluate fluoroscopy time, dose area product (DAP) during electrophysiology procedures, assess factors attributing to their variation and to suggest possible ways to reduce X-ray exposure. Methods: Data of 907 patients, undergoing treatment for atrioventricular nodal re-entrant tachycardia, atrial fibrillation, atrial flutter, concealed or manifesting Wolff–Parkinson–White syndrome, ventricular tachycardia, ventricular extrasystole, His bundle radiofrequency ablations, de novo CRT device implantation between 2015 and 2016 and performed by 4 physicians, were included in the analysis. Registered DAP, procedure outcome, fluoroscopy framerate and duration data were assessed. Continuous variables not normally distributed are expressed as means, medians. Categorical variables are expressed as absolute values, percentages. Comparison of independent samples was done using Kruskal–Wallis test. To evaluate categorical data differences Chi-squared test was used. Differences were considered statistically significant if p values < 0.05. SPSS 24 was used for statistical analysis.[...].

BACKGROUND: Approximately 30% of patients treated with cardiac resynchronization therapy (CRT) do not achieve favourable response. The purpose of the present study was to identify echocardiographic and clinical predictors of a positive response to CRT. METHODS: The study included 82 consecutive heart failure (HF) patients in New York Heart Association (NYHA) functional class III or IV with left bundle branch block (LBBB), QRS duration >= 120 ms and left ventricular ejection fraction (LVEF) <= 35%. Statistical analysis was performed using IBM SPSS statistical software (SPSS v.21.0 for Mac OS X). A p value < 0.05 was considered statistically significant. RESULTS: Echocardiographic response was established in 81.6% and clinical response was achieved in 82.9% of patients. Significant univariate predictors of favourable echocardiographic response after 12 months were smaller left ventricular end-diastolic diameter (LVEDD) (odds ratio [OR] 0.89; 95% confidence interval [CI] 0.82 - 0.97, p = 0.01), and smaller left ventricular end-systolic diameter (LVESD) (OR 0.91; 95% CI 0.85 - 0.98, p = 0.01). Lower uric acid concentration was associated with better echocardiographic response (OR 0.99; 95% CI 0.99 - 1.0, p = 0.01). Non-ischemic HF etiology (OR 4.89; 95% CI 1.39 - 17.15, p = 0.01) independently predicted positive clinical response. Multiple stepwise regression analysis demonstrated that LVEDD lower than 75 mm (OR 5.60; 95% confidence interval [CI] 1.36 - 18.61, p = 0.01) was the strongest independent predictor of favourable echocardiographic response. CONCLUSIONS: Smaller left ventricular end-diastolic and end-systolic diameters and lower serum uric acid concentration were associated with better response to CRT. Left ventricular end-diastolic diameter and non-ischemic heart failure etiology were the strongest independent predictors of positive response to CRT.

Purpose. To compare the results of the cardiac resynchronization therapy (CRT) between the ischemic and non-ischemic cardiomyopathy groups, one year follow-up of CRT. Methods. Seventy there patients (=73). 26 patients had ischemic and 37 – nonischemic cardiomyopathy, with standard CRT indications. The study lasted for 12 months. All patients were assessed by standard two dimensional echocardiography at baseline prior to CRT and after 12 months post-CRT. Statistical analysis was performed using SPSS version 20.0. The data were presented as men, standard deviation and 95% confidence interval and compared using T test. If the data were asymmetric and nonnormally distributed they were presented as median, 1st and 3rd quartiles (Q1; Q3) and compared using Mann-Whitney U test instead. Results. After 12 months post-CRT a significant difference was revealed between the ischemic and non-ischemic cardiomyopathy groups in terms of mean EF 28.5% ± 8.4, 95% Cl (25.1; 31.9) versus 33.4% ± 9.3, 95% Cl (30.3; 36.5), t (61) = -2.149, p=0.036, medium LVEDV 184ml (161.5; 240) versus 145ml (111; 197), U=304, z=-2.002, p=0.045 and LVESV 146ml (98.5; 176.5) versus 100ml (75.25; 143.25), U=291, z=-2.056, p=0.039, respectively. [graf.]. Conclusions. Cardiac resynchronization therapy is less effective in patients with ischemic cardiomyopathy in comparison to the nonischemic cardiomyopathy group, after 12 months post-CRT.

BACKGROUND: In treatment of atrial fibrillations (AF), radiofrequency ablation (RFA) at the pulmonary vein (PV) roots isolates AF triggers in the myocardial sleeves, but also can destroy PV ganglia and branches of the intrinsic cardiac nerve plexus. AIM: To determine the long-term impact of RFA at the PV roots on the structure of epicardial nerves located distally from the RFA site. METHODS: Five black-faced sheep underwent epicardial RFA of the left and middle PV roots. Two to 3months after RFA, we obtained samples of epicardial nerves from remote locations of the left dorsal (LD) neural subplexus that extends along the roots of the superior PVs toward the coronary sinus (CS) and dorsal left ventricle (LV). Right atrial epicardial nerves from the right ventral (RV) neural subplexus of the ablated animals and epicardial nerves from LD neural subplexus of five additional intact sheep were used as control. Nerve morphology was examined using histochemical, immunohistochemical and transmission electron microscopy. RESULTS: Histochemical acetylcholinesterase staining did not reveal any epicardial nerve alterations. However, tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) staining showed clearly the reduced numbers of TH and ChAT immunoreactive (IR) nerve fibers within epicardial nerves derived from the remote LD subplexus; control samples from all examined animals were full of evenly distributed TH-IR and ChAT-IR nerve fibers. In sharp contrast to control nerves, numerous swollen or disintegrated axons and Schwann cells with pyknotic nuclei inside unmyelinated and myelinated nerve fibers were identified by electron microscopy of ultrathin sections of epicardial nerves from the CS and LV regions in all ablated animals. CONCLUSIONS: Degeneration of remote atrial and ventricular epicardial nerves is evident 2-3months after epicardial RFA at the PV roots. Such nerves are likely to be non-functional. [...].

Background: Most of the cardiac arrhythmias recently are corrected by using radiofrequency ablation (RFA), but rate of post-operative complications remains not inconsiderable, mechanisms of which are unknown. We tried to determine the optimal destruction characteristics of RFA in to the cardiac tissue and compare them with cryo-destruction effect. Methods: 20-25 kg female pigs (n-21) were used. Destruction with standard 4 and 8 mm "Biosence Webster" electrodes was performed from the endocardial side by inserting the electrode through incision on the apex of the right or left auricle. Destruction parameters: energy - 20-50 W, time - 10-30 sec in auricles and 20-60 in ventricles. The tissues temperature changes were supervised and registered with IR camera "ThermaCAM P640", sensitivity ≤0.05°C, and emissivity α=0.98. Thermographic views were analyzed with "ThermaCAM Researcher Prof" computer software. Results: RFA thermo effect (>46°C) on atrial epicardium observed after 5-7 sec., independently from energy power and the type of the electrode. 20-30W energy showed ellipse from full destruction area 3-4 mm in the diameter, when using 50W -respectively 5-7 mm. At 30W and 30 s complete and partial destruction zone mostly coincide. [...].

Purpose: To estimate the functional changes of the right heart during cardiac resynchronization therapy (CRT). Methods: 37 patients meeting ESC recommended CRT implantation indications were included into this study. The size of the right ventricle (RV), the volume of the right atrium (RA), tricuspid annular plane systolic excursion (TAPSE) and the highest tricuspid annular systolic velocity (TASV) were evaluated before CRT and after 3 and 6 months. Statistical analysis was performed using SPSS version 15.0. Results: Mean initial RV sizewas 34.95 ± 8.6 mm., after 3months of CRT in responders’ and non – responders’ group it was 34.02 ± 8.45 mm and 35.67 ± 8.88 mm, respectively, after 6 months – 34.82 ± 7.9 mm and 34.45 ± 10.23 mm, respectively. Mean initial RA volume was 82.31 ± 39.3 ml., after 3 months of CRT in responders’ and non – responders’ group it was 48.9 ± 10.46 ml and 89.75 ± 35.12 ml, respectively, after 6 months – 65.62 ± 25.23 ml and 70.0 ± 24.2 ml, respectively. Mean initial TAPSE was 12.92 ± 5.62 mm., after 3 months of CRT in responders’ and non – responders’ group it was 14.5 ± 3.1 mm and 11.9 ± 5.7 mm, respectively, after 6 months – 14.52 ± 3.9 mm and 14.5 ± 3.15 mm, respectively. Mean highest initial TASV was 11.03 ± 3.37 cm/s., after 3 months of CRT in responders’ and non – responders’ group it was 13.0 ± 4.0 cm/s and 10.56 ± 3.94 cm/s, respectively, after 6 months – 13.15 ± 3.77 cm/s and 12.0 ± 3.0 cm/s, respectively. Mean initial RA correlated with mean initial RV and highest TASV. We found a high positive correlation (r > 0.5) between the reduction of mean RA and the increase of LV EF and TASV in responders’ group after 3 months. Conclusions: 1 During CRT the structure and function of the right heart does change. 2 Even in non – responders’ group the function of RV does improve. 3 Severe dilation of the RA might be the

Purpose: To estimate the structural changes of the right heart during cardiac resynchronization therapy (CRT). Methods: 37 patients meeting ESC recommended CRT implantation indications were included into this study. The size of the right ventricle (RV), the volume of the right atrium (RA), right ventricle myocardial performance index (RV MPI), tricuspid annular plane systolic excursion (TAPSE) and the highest tricuspid annular systolic velocity (TASV) were evaluated before starting CRT and after 3 and 6 months of treatment. Statistical analysis was performed using SPSS version 15.0. Results: Mean initial RV size was 34.95 ± 8.6 mm., after 3 months of CRT in responders’ and non – responders’ group it was 34.02 ± 8.45 mm and 35.67 ± 8.88 mm, respectively, after 6 months – 34.82 ± 7.9 mm and 34.45 ± 10.23 mm, respectively. Mean initial RA volume was 82.31 ± 39.3 ml., after 3 months of CRT in responders’ and non – responders’ group it was 48.9 ± 10.46 ml and 89.75 ± 35.12 ml, respectively, after 6 months – 65.62 ± 25.23 ml and 70.0 ± 24.2 ml, respectively. Mean initial RA and mean RA after 3 months appeared to differ significantly (p < 0.05) between the responders’ and non – responders’ groups. Mean initial RA correlated with mean initial RV and highest TASV. We found a high positive correlation (r > 0.5) between the reduction of mean RA and the increase of LV EF and TASV in responders’ group after 3 months. after 3 months. Conclusions: 1 During CRT the structure of the right heart does change. 2 The difference of the mean initial RA volume and mean RA volume after 3 months of CRT between responders’ and non – responders’ was statistically significant. 3 Severe dilation of the RA might be the prognostic sign of the absence of the response to CRT.