Long-term single-centre large volume experience with transseptal endocardial left ventricular lead implantation.

AIMS: The aim of our study was to investigate the long-term efficacy and safety of transseptal endocardial left ventricular lead implantation (TELVLI). METHODS AND RESULTS: Transseptal endocardial left ventricular lead implantation was performed in 54 patients (44 men, median age 69, New York Heart Association III-IV stage) between 2007 and 2017 in a single centre. In 36 cases, the transseptal puncture (TP) was performed via the femoral vein, and in 18 cases, the TP and also the left ventricular (LV) lead placement were performed via the subclavian vein. An electrophysiological deflectable catheter was used to reach the LV wall through the dilated TP hole. The LV lead implantation was successful in all patients. A total of 54 patients were followed up for a median of 29 months [interquartile range (IQR) 8-40 months], the maximum follow-up time was 94 months. Significant improvement in the LV ejection fraction was observed at the 3-month visit, from the median of 27% (IQR 25-34%) to 33% (IQR 32-44%), P < 0.05. Early lead dislocation was observed in three cases (5%), reposition was performed using the original puncture site in all. The patients were maintained on anticoagulation therapy with a target international normalized ratio between 2.5 and 3.5. Four thromboembolic events were noticed during follow-up. A total of 27 patients died, with a median survival of 15 months (IQR 6-40). CONCLUSION: The TELVLI is an effective approach for cardiac resynchronization therapy (CRT) however it is associated with a substantial thromboembolic risk (7%).

Quality of life measured with EuroQol-five dimensions questionnaire predicts long-term mortality, response, and reverse remodelling in cardiac resynchronization therapy patients.

Aims: There are previous studies on quality of life (QoL) in cardiac resynchronization therapy (CRT) patients; however, there are no data with the short EuroQol-five dimensions (EQ-5D) questionnaire predicting outcomes. We aimed to assess the predictive role of baseline QoL and QoL change at 6 months after CRT with EQ-5D on 5-year mortality and response. Methods and results: In our prospective follow-up study, 130 heart failure (HF) patients undergoing CRT were enrolled. Clinical evaluation, echocardiography, and EQ-5D were performed at baseline and at 6 months of follow-up, continued to 5 years. Primary endpoint was all-cause mortality at 5 years. Secondary endpoints were (i) clinical response with at least one class improvement in New York Heart Association without HF hospitalization and (ii) reverse remodelling with 15% reduction in left ventricular end-systolic volume at 6 months. Fifty-four (41.5%) patients died during 5 years, 85 (65.3%) clinical responders were identified, and 63 patients (48.5%) had reverse remodelling. Baseline issues with mobility were associated with lower response [odds ratio (OR) 0.36, 95% confidence interval (CI) 0.16-0.84; P = 0.018]. Lack of reverse remodelling correlated with self-care issues at baseline (OR 0.10, 95% CI 0.01-0.94; P = 0.04). Furthermore, self-care difficulties [hazard ratio (HR) 2.39, 95% CI 1.17-4.86; P = 0.01) or more anxiety (HR 1.51, 95% CI 1.00-2.26; P = 0.04) predicted worse long-term survival. At 6 months, mobility (HR 3.95, 95% CI 1.89-8.20; P < 0.001), self-care (HR 7.69, 95% CI 2.23-25.9; P = 0.001), or ≥ 10% visual analogue scale (VAS) (HR 2.24, 95% CI 1.27-3.94; P = 0.005) improvement anticipated better survival at 5 years. Conclusion: EuroQol-five dimension is a simple method assessing QoL in CRT population. Mobility issues at baseline are associated with lower clinical response, whereas self-care issues predict lack of reverse remodelling. Problems with mobility or anxiety before CRT and persistent issues with mobility, self-care, and VAS scale at 6 months predict adverse outcome.

Minimal Invasive Left Ventricular Lead Repositioning is Safe and Effective in Distal Left Ventricular Lead Positions.

BACKGROUND: Treatment of left ventricular electrode dislocation and phrenic nerve stimulation remains an issue in the era of new electrode designs. METHODS: Safety and efficacy of minimal invasive lead repositioning and pocket opening reposition procedures were evaluated between December 2005 and December 2012 at our center. Minimal invasive method was developed and widely utilized at our center to treat phrenic nerve stimulation. The distally positioned left ventricular lead is looped around by a deflectable catheter in the right atrium introduced from the femoral vein access and then pulled back. Coronary stent implantation was used afterwards for lead stabilization in some patients. RESULTS: 42 minimal invasive and 48 electrode repositions with pacemaker pocket opening were performed at 77 patients for left ventricular lead problems. Minimal invasive reposition could be carried out successfully in 69% of (29 patients) cases. Note that in 14.3% of the cases (six patients) minimal invasive procedures were acutely unsuccessful and crossover was necessary. In 16.6% of the cases (seven patients) lead issues were noted later during follow-up. Opening of the pocket could be carried out successfully in 81.2% (39 patients) and was unsuccessful acutely in 6.25% (three patients). Repeated dislocation was noticed, 12.5%, in this group (six patients). Complication during minimal invasive procedures was electrode injury in one case. Pocket openings were associated with several complications: atrial fibrillation, pericardial effusion, fever, hematoma, and right ventricular electrode dislodgement. CONCLUSION: Minimal invasive procedure-as the first line approach-is safe and feasible for left ventricular electrode repositioning in selected cases.

Complement C3a predicts outcome in cardiac resynchronization therapy of heart failure.

BACKGROUND: The chronic inflammation plays an important role in heart failure and complement components might be useful markers of the prognosis. We set out to evaluate their predictive value in the clinical outcomes of patients with cardiac resynchronization therapy (CRT). METHODS: We determined the complement levels C3, C3a, sC5b-9 and also the N-terminus of the prohormone brain natriuretic peptide (NT-proBNP) of 126 heart failure patients in a prospective, single-center observational study before and 6 months after CRT implantation. RESULTS: CRT reduced the C3a [212.5 (148.2-283.6) vs. 153 (119.8-218.3) ng/mL, p < 0.0001] and the sC5b-9 levels [296.9 (234.2-358.8) vs. 255.1 (210.1-319.0) ng/mL, p = 0.0006], but not the total C3 levels [1.43 (1.26-1.61) vs. 1.38 (1.23-1.57) g/L, p = 0.57]. C3a predicted the 5-year mortality of the patients [C3a > 165 ng/mL hazard ratio = 4.21 (1.65-10.72), p = 0.003] independent of the NT-proBNP and other factors. After reclassification, we observed a significant net reclassification improvement [NRI = 0.71 (0.43-0.98), p < 0.0001] and integrated discrimination improvement [IDI = 0.08 (0.03-0.12), p = 0.0002]. CONCLUSIONS: In patients with CRT, elevated C3a levels increase the risk of mortality independent of the NT-proBNP levels or other factors. CRT exerts anti-inflammatory effect by reducing the complement activation.

Longer right to left ventricular activation delay at cardiac resynchronization therapy implantation is associated with improved clinical outcome in left bundle branch block patients.

AIMS: Data on longer right to left ventricular activation delay (RV-LV AD) predicting clinical outcome after cardiac resynchronization therapy (CRT) by left bundle branch block (LBBB) are limited. We aimed to evaluate the impact of RV-LV AD on N-terminal pro-B-type natriuretic peptide (NT-proBNP), ejection fraction (EF), and clinical outcome in patients implanted with CRT, stratified by LBBB at baseline. METHODS AND RESULTS: Heart failure (HF) patients undergoing CRT implantation with EF ≤ 35% and QRS ≥ 120 ms were evaluated based on their RV-LV AD at implantation. Baseline and 6-month clinical parameters, EF, and NT-proBNP values were assessed. The primary endpoint was HF or death, the secondary endpoint was all-cause mortality. A total of 125 patients with CRT were studied, 62% had LBBB. During the median follow-up of 2.2 years, 44 (35%) patients had HF/death, 36 (29%) patients died. Patients with RV-LV AD ≥ 86 ms (lower quartile) had significantly lower risk of HF/death [hazard ratio (HR): 0.44; 95% confidence interval (95% CI): 0.23-0.82; P = 0.001] and all-cause mortality (HR: 0.48; 95% CI: 0.23-1.00; P = 0.05), compared with those with RV-LV AD < 86 ms. Patients with RV-LV AD ≥ 86 ms and LBBB showed the greatest improvement in EF (28-36%; P<0.001), NT-proBNP (2771-1216 ng/mL; P < 0.001), and they had better HF-free survival (HR: 0.23, 95% CI: 0.11-0.49, P < 0.001) and overall survival (HR: 0.35, 95% CI: 0.16-0.75; P = 0.007). There was no difference in outcome by RV-LV AD in non-LBBB patients. CONCLUSION: Left bundle branch block patients with longer RV-LV activation delay at CRT implantation had greater improvement in NT-proBNP, EF, and significantly better clinical outcome.

Comparison of the Effects of Epicardial and Endocardial Cardiac Resynchronization Therapy on Transmural Dispersion of Repolarization.

BACKGROUND: Despite significant improvements in cardiac output and functional capacity with cardiac resynchronization therapy (CRT), incidence of sudden cardiac death still remains high. Reversal of physiological myocardial activation sequence during epicardial pacing increases the transmural dispersion of repolarization (TDR). The aim of this study was to compare the effects of endocardial and epicardial biventricular pacing on repolarization parameters in the same patient group. METHODS: Seven patients who had transseptal endocardial left ventricle (LV) lead placement, in whom epicardial CRT had failed due to coronary sinus (CS) lead dislodgement after successful implantation, were admitted to the study. LV endocardial leads were implanted through the interatrial septum in a lateral position. Electrocardiograms (ECGs) were scanned before and after successful epicardial and endocardial biventricular pacing and analyzed using digital calipers. ECG markers of TDR (TpTe and TpTe/QT ratio) were measured and compared. RESULTS: Baseline QRS durations (161.7 ± 15.9 ms vs 162.2 ± 17.8 ms, P = 0.95), TpTe values (107.1 ± 20.5 ms vs 108.5 ± 17.6 ms, P = 0.89), and TpTe/QT ratios (0.24 ± 0.05 vs 0.24 ± 0.03, P = 0.88) were similar before epicardial and endocardial CRT. QRS interval reduction was similar (-28.3 ± 11.6 ms vs -29.1 ± 11.4 ms, P = 0.89) in both groups. Compared to transseptal endocardial CRT, epicardial CRT was associated with a significant increase in TpTe (17.1 ± 19.5 ms vs -12.6 ± 18.9 ms, P = 0.01) and TpTe/QT ratio (0.03 ± 0.04 vs -0.02 ± 0.03, P = 0.04). CONCLUSION: Transseptal LV endocardial pacing is associated with significant reduction in TDR characteristics compared to epicardial pacing in CRT. Further studies are warranted to determine whether these effects may contribute to reduction of arrhythmias in patients with CRT.

Methods for examination an explanted coronary sinus lead stabilized with a coronary stent.

The aim of our investigation was to test the suitability of a novel method for the analysis of the integrity of an explanted pacemaker lead stabilized by a stent. A coronary sinus lead has been explanted 27 months after implantation and has been examined by optical-, confocal-, x-ray-, and scanning electron microscopy. Several surface injuries were found on the insulation. Based on the surface characteristics, it is possible to define and differentiate the source of damages as well as to measure the extent of injuries. Impedance of the explanted lead has also been measured and electronic integrity has been verified.

Usefulness of electroanatomical mapping during transseptal endocardial left ventricular lead implantation.

AIM: Failure rate to implant left ventricular (LV) lead transvenously is 4-8% in cardiac resynchronization therapy (CRT) patients. Epicardial lead placement is an alternative method and if not applicable case reports and small series showed the feasibility of endocardial LV lead implantation. Electroanatomical mapping might be a useful tool to guide this procedure. METHODS AND RESULTS: Four patients had undergone endocardial LV lead implantation after unsuccessful transvenous implantation or epicardial LV lead dysfunction using the transseptal approach. Electroanatomical mapping was used to mark the location of the transseptal puncture. This location point guided the mapping catheter from the subclavian access and facilitated positioning of the LV lead at the adjacent latest activation area of the left ventricle detected by activation mapping. Endocardial active fixation LV leads were successfully implanted in all patients with stable electrical parameters immediately after implantation and over a mean follow-up of 18.3 months (lead impedance 520 ± 177 vs. 439 ± 119 Ω and pacing threshold 0.8 ± 0.2 V, 0.5 ms vs. 0.6 ± 0.1 V, 0.5 ms, respectively). Patients were maintained on anticoagulation therapy with a target international normalized ratio of 3.5-4.5 and did not show any thromboembolic, haemorrhagic events, or infection. Echocardiography showed significant improvement of LV systolic function with marked improvement of the functional status. CONCLUSIONS: Electroanatomical mapping is a useful technical tool to guide endocardial LV lead implantation. It helps to identify the location of the transseptal puncture and the use of activation mapping might facilitate location of the optimal lead positions during CRT.

Recurrent arterial thrombosis associated with the antithrombin basel variant and elevated lipoprotein(a) plasma level in an adolescent patient.

Both myocardial infarction and ischemic stroke are rare in the young. Yet a 15-year-old male patient suffered a myocardial infarction and later an ischemic stroke despite uninterrupted antiplatelet therapy. His medical history involved the surgical correction of an incomplete atrioventricular canal defect at the age of 13 years. No cardiovascular risk factors other than elevated lipoprotein(a) level could be identified. His antithrombin (AT) activity was decreased and DNA sequence analysis revealed heterozygosity for AT Basel (p.Pro41Leu), a variant with impaired heparin binding. This report supports a possible additional pathophysiological role for AT Basel and elevated lipoprotein(a) level in arterial thrombogenesis.

[Electroanatomical mapping and radiofrequency ablation of tachycardia originating in pulmonary vein in an adult patient]. / Fiatalkori vena pulmonalis tachycardia ablatiója elektroanatómiai térképezés segítségével.

A 29-year-old male was admitted to our outpatient clinic because of palpitation and documented narrow QRS arrhythmia. Based on the ECG, supraventricular tachycardia was diagnosed, electrophysiological examination was indicated and ablation therapy was recommended. During positioning of the catheter the patient developed arrhythmia. On the coronary sinus catheter the activation spread from distal to proximal electrodes, suggesting left atrial origin. During atrial entrainment pacing long return cycle was observed and distal coronary sinus pacing resulted in a 15 ms longer cycle length than the arrhythmia. Therefore, the left atrial origin of the arrhythmia was confirmed and double transseptal puncture was performed. Lasso and irrigated tip catheter were introduced into the left atrium and electroanatomical mapping was performed with CARTO3 system. After electroanatomical mapping the origin of tachycardia was located proximally in the left superior pulmonary vein. Ablation was started at the earliest activation point, where acceleration was observed and the arrhythmia stopped after the first ablation. Pulmonary vein isolation was completed, and bidirectional block could be confirmed. After 30 minutes the arrhythmia was not inducible. During follow-up, Holter-examination was negative and the patient remained asymptomatic. The pulmonary vein tachycardia is a supraventricular arrhythmia that can occur at any age, but the diagnosis based on the ECG is not always simple. Detailed electroanatomical mapping is very important in the diagnosis of this type of arrhythmia, although it can be verified with conventional electrophysiological methods as well. Focal ablation may be a therapeutic option; however, total isolation of pulmonary veins can be more effective.

[Physiologic effects of hypothermia]. / A hypothermia élettani hatásai.

Therapeutic use of hypothermia has come to the frontline in the past decade again in the prevention and in mitigation of neurologic impairment. The application of hypothermia is considered as a successful therapeutic measure not just in neuro- or cardiac surgery, but also in states causing brain injury or damage. According to our present knowledge this is the only proven therapeutic tool, which improves the neurologic outcome after cardiac arrest, decreasing the oxygen demand of the brain. Besides influencing the nervous system, hypothermia influences the function of the whole organ system. Beside its beneficial effects, it has many side-effects, which may be harmful to the patient. Before using it for a therapeutic purpose, it is very important to be familiar with the physiology and complications of hypothermia, to know, how to prevent and treat its side-effects. The purpose of this article is to summarize the physiologic and pathophysiologic effects of hypothermia.

Programmed Death-ligand 1 (PD-L1) Expression in Thymic Epithelial Tumors.

Thymic epithelial tumors (TETs) are uncommon neoplasms of the mediastinum. The gold standard treatment is complete surgical resection which can be followed by radio/chemotherapy in selected cases. Targeted tyrosine kinase inhibition can be considered in only a limited number of aggressive or metastatic tumors as EGFR, BRAF, or c-kit mutations are rare. However, previous studies have demonstrated the efficacy of immune checkpoint inhibitors in epithelial neoplasias, such as in programmed cell death ligand 1 (PD-L1) expressing nonsmall cell lung carcinoma. Because of their rare occurrence the data on PD-L1 distribution in thymic neoplasias are limited. PD-L1 and PD-1 expression in tumor cells and tumor infiltrating immune cells was determined in TETs according to criteria published for lung carcinomas. Comparison with major clinical, pathologic, and biological features was also done. In total, 36 TETs (29 thymomas and 7 thymic carcinomas) were analyzed. PD-L1 immunohistochemical staining (Ventana PD-L1 clone SP142) was performed in all cases. The percentage of the positive tumor cells (TC value), the percentage of tumor area occupied by positive immune cells (IC value) was evaluated. Evaluation of PD-L1 expression in tumor cells showed a good reproducibility (κ-value: 0.840; Spearman r=0.966; P<0.0001). About 69% of thymomas (20/29) and 43% of thymic carcinomas (3/7) showed high positivity rate (TC≥50% or IC ≥10%), which may indicate therapeutic advantage similar to nonsmall cell lung cancers defined by the same conditions. PD-L1 expression is common in different epithelial tumors of the thymus, which suggests the potential effectiveness of drugs targeting the PD-1/PD-L1 interactions in these neoplasms.

[Ablation of idiopathic fascicular ventricular tachycardia]. / Idiopathiás fascicularis kamrai tachycardia ablatiója.

Idiopathic fascicular ventricular tachycardia is an important and not very rare cardiac arrhythmia with specific electrocardiographic features and therapeutic options. Ventricular tachycardia is characterized by relatively narrow QRS complex and right bundle branch block pattern. The QRS axis depends on which fascicle is involved in the re-entry. Left axis deviation is noted with left posterior fascicular tachycardia and right axis deviation with left anterior fascicular tachycardia. A left septal fascicular tachycardia with normal QRS axis is also possible. Idiopathic fascicular tachycardia is usually seen in individuals without structural heart disease. Response to verapamil is an important feature of fascicular tachycardia. In some cases intravenous adenosine may also terminate the arrhythmia. During electrophysiology study, presystolic or diastolic potentials precede the QRS, presumed to originate from the Purkinje fibers. The potentials can be recorded during sinus rhythm and ventricular tachycardia in many patients with fascicular tachycardia. This potential (so-called Purkinje potential) has been used as a guide to catheter ablation. Correct diagnosis of fascicular tachycardia is very important because catheter ablation is very effective in the treatment of this type of ventricular tachycardia. In this review, we describe three patients with idiopathic ventricular tachycardia and their successful catheter ablation, and summarize the actual knowledge of the diagnosis and management of this special ventricular tachycardia.

Novel Biomarkers in Cardiac Resynchronization Therapy: Hepatocyte Growth Factor Is an Independent Predictor of Clinical Outcome.

INTRODUCTION AND OBJECTIVES: Cardiac resynchronization therapy (CRT) is beneficial for selected heart failure (HF) patients, although nonresponse to therapy is still prevalent. We investigated a set of novel biomarkers associated with various pathophysiological pathways of HF. Our purpose was to assess their ability to predict clinical outcomes after CRT. METHODS: We studied 136 chronic HF patients undergoing CRT. We measured the plasma levels of fractalkine, pentraxin-3, hepatocyte growth factor (HGF), carbohydrate antigen-125, and matrix metalloproteinase-9 before and 6 months after CRT. The primary endpoint of the study was 5-year all-cause mortality, and we considered the absence of 6-month reverse remodelling (defined as at least a 15% decrease in end-systolic volume) as a secondary endpoint. RESULTS: Fifty-eight patients died during the 5-year follow-up period and 66 patients were categorized as nonresponders. In multivariable models, only an increased HGF was an independent predictor of both mortality (HR, 1.35; 95%CI, 1.11-1.64; P=.003; per 1 standard deviation increase) and the absence of reverse remodelling (OR, 1.83; 95%CI, 1.10-3.04; P=.01; per 1 standard deviation increase). Applying HGF to the basic multivariable model of both mortality (net reclassification improvement=0.69; 95%CI, 0.39-0.99; P<.0001; integrated discrimination improvement=0.06; 95%CI, 0.02-0.11) and reverse remodelling (net reclassification improvement=0.39; 95%CI, 0.07-0.71; P=.01; integrated discrimination improvement=0.03; 95%CI, 0.00-0.06) resulted in a statistically significant reclassification and discrimination improvement. CONCLUSIONS: Of the investigated biomarkers, only HGF predicted clinical outcomes following CRT independently of other parameters. Reclassification analyses showed that HGF measurements could be useful in refining patient selection.

[Assessment of the extent of myocardial necrosis following radiofrequency catheter ablation of different supraventricular arrhythmias]. / A myocardialis necrosis mértékének vizsgálata eltéro supraventricularis szívritmuszavarok rádiófrekvenciás katéterablatiós kezelését követoen.

INTRODUCTION: Levels of cardiac necroenzymes, high-sensitive troponin (hsTnT) and creatine kinase muscle-brain (CKMB) increase as a result of a myocardial damage following catheter ablation. AIM: To analyze the mid-term alteration of hsTnT and CKMB levels following radiofrequency ablation (RFCA) for atrial fibrillation (AF), atrial flutter (AFlu), AV-nodal reentry tachycardia (AVNRT) and electrophysiological studies (EPS) without ablation. METHOD: Patients undergoing RFCA for various indications and EPS were consecutively enrolled in our prospective study. Concentrations of hsTnT and CKMB were measured from serial blood samples directly before and after the procedure, 4 and 20 hours later and at 3 months follow-up. RESULTS: Forty-seven patients (10 EPS, 12 AVNRT, 13 AFlu, 12 AF) with mean age of 55 ± 13 were included. hsTnT levels increased significantly in all groups after the procedures, while CKMB changed only in the AF group. hsTnT exceeded the reference value in all patients with ablation and in 80% of patients with EPS 4 hours post-ablation. Peak average hsTnT levels for EPS, AVNRT, AFlu were 24 ± 11, 260 ± 218 and 541 ± 233 ng/L, respectively. The highest hsTnT level was measured in the AF group (799 ± 433 ng/L). We found a positive correlation between hsTnT levels and ablation time after RFCA. CONCLUSIONS: The hsTnT levels significantly change after EPS and RFCA, in all patients who underwent ablation, and in 80% of those with EPS had hsTnT positivity in the early post-procedural phase. hsTnT levels depended significantly on the type of the subgroups and correlated with the ablation time. Awareness of those observations is essential to correctly interpret elevated hsTnT levels following RFCA. Orv Hetil. 2019; 160(14): 540-548.

Minimal invasive coronary sinus lead reposition technique for the treatment of phrenic nerve stimulation.

AIMS: Phrenic nerve stimulation (PNS), which is often intolerable for the patient, is a known complication of resynchronization therapy. We describe a new, minimal invasive method for treating PNS. METHODS AND RESULTS: Untreatable PNS was found in nine cardiac resynchronization therapy patients with distal coronary sinus (CS) lead position 6 +/- 6 (0.5-17) months after the implantation. Ablation catheter and Amplatz Left 2 type guiding catheter were introduced into the right atrium via the right femoral vein. Coronary sinus was cannulated with the Amplatz catheter, and on a normal guide wire, a coronary stent was introduced beside the lead into the side branch in seven cases or a bigger stent into the CS in two patients. The ablation catheter was looped around the CS lead in the atrium with bent tip and was drawn backward together with the CS electrode. New lead positions were evaluated with electrophysiological measurements, and the suitable position was stabilized with inflation of the stent. Pericardial effusion was not detected on post-operative echocardiography. After repositioning, suitable pacing parameters were registered (threshold: 1.6 +/- 1.1 V; 0.5 ms, impedance: 565 +/- 62 ohm). Phrenic nerve stimulation was not found with 7.5 V; 1.5 ms pacing. During follow-up (7.7 +/- 4.6 months), stable pacing threshold and impedance values were measured; transient and reprogrammable PNS was present in only one patient. CONCLUSION: Coronary sinus electrode reposition using the femoral approach seems to be a safe and effective procedure, which means smaller burden for the patients compared with the established reposition operation. The technique can be used successfully if the CS lead is in a distal position.

Successful cardiac resynchronization therapy after heart transplantation.

We describe a case of a 56-year-old male patient, who developed refractory dilated cardiomyopathy 5 years after heart transplantation. An atriobiventricular pacemaker was implanted when indication criteria of cardiac resynchronization therapy (CRT) were seen. The intraventricular dyssynchrony was significant before CRT, while synchronous contraction was demonstrated later with the beneficial reverse remodelling of the left ventricle. Resynchronization therapy resulted in significant improvement of the patient's clinical parameters. The success of this therapy points out the possible role of CRT in the treatment of chronic allograft failure after heart transplantation.

Electrical atrial fibrillation induction affects the characteristics of induced arrhythmia.

Several methods are being used to induce atrial fibrillation (AF) in experimental investigations, which may affect the electrophysiologic parameters of the induced arrhythmia. The aim of our study was the investigation of temporal characteristics of AF during and after electrical induction. Direct current and high-frequency stimulation was used for induction in bipolar biatrial, right and left atrial appendage configurations in 6 dogs. Atrial and ventricular electrical activity was recorded near the bundle of His. Seven statistical parameters were calculated to analyze the temporal characteristics of electrical activity of both chambers. The induction method affected 5 atrial and no ventricular electrophysiologic parameters during stimulation, and the effect disappeared after ceasing induction, during the induced transient or persistent AF. Electrical stimulation affects the properties of the induced arrhythmia during the induction; thus, the investigation of AF is recommended only after ceasing the induction to avoid bias.

[Successful epicardial ablation of a postinfarction ventricular tachycardia]. / Posztinfarktusos incessant kamrai tachycardia sikeres epicardialis katéterablatiója. Az elso hazai esetismertetés.

Endocardial radiofrequency catheter ablation was performed because of frequent, 150/min monomorphic ventricular tachycardia (VT). In February 2005 it was many times terminated only by ICD shock in a 55-year-old postinfarction patient who received an implantable cardioverter defibrillator (ICD) 5 years ago because of rapid, monomorphic VT. After being asymptomatic for two months, a slower, 120/min, however, incessant ventricular tachycardia was present which was untreatable by a repeated endocardial ablation. Combined antiarrhythmic treatment was not effective either. In June 2005, after another unsuccessful endocardial ablation, epicardial ablation was decided as an "ultimum refugium". After subxyphoidal percutaneous pericardial punction we positioned the ablation catheter in the pericardial space, and ablation at the earliest activation point terminated the permanently ongoing arrhythmia for one and a half month within 5 seconds. After another three ablations we were unable to induce ventricular arrhythmia even with programmed ventricular extrastimulation. During a three-year follow-up, ventricular tachycardia was noticed in only two cases, ICD terminated both arrhythmias with the first antitachycardia pacing. The patient is in NYHA stage II at present. According to our knowledge, our case is the first successful epicardial ablation of incessant ventricular tachycardia in a postinfarction patient in Hungary.

[Intracardiac echocardiography-guided cardiac tumor mass biopsy]. / Intracardialis echokardiográfia-vezérelt cardialis tumormassza-biopszia.

Primary cardiac tumors are rare and often occur without major symptoms. The appropriate therapy for cardiac tumors without metastasis is surgical resection and chemotherapy. However, for certain patients, when the tumor cannot be safely removed, biopsy is recommended since it allows histology examination and further therapeutical considerations. The aim of our case presentation is to describe the case of a 56-year-old woman, in whom cardiac tumor-mass was revealed because of recurrent pericardial fluids. The mass appeared to be non-resectable, therefore biopsy with an eventual histological examination was planned. Intracardiac echocardiography guided percutaneous biopsy was performed. Intracardiac ultrasound ensured accurate localization of the tumor, the catheter-based grasping device and the excision could be instantly monitored. This case demonstrates that an intracardiac ultrasound-guided tumor mass biopsy is a feasible method, which increases accuracy and ensures safety.