Dietary Therapy in Prevention of Cardiovascular Disease (CVD)-Tradition or Modernity? A Review of the Latest Approaches to Nutrition in CVD.

The development of cardiovascular diseases is undoubtedly influenced by improper dietary behavior. The most common mistakes include irregularity of meal consumption, high dietary atherogenicity: snacking on sweets between meals, low supply of dietary fiber, unsaturated fatty acids, legume seeds, and high supply of meat and meat products. Among many food components, some are characterized by a specific cardioprotective effect, which means that their supply of food may prevent the occurrence of cardiovascular disease or improve the health of the sick. Coenzyme Q10 (CoQ10) is one of the ingredients showing cardioprotective effects on the heart and blood vessels. Antioxidant and lipid profile-enhancing effects are also attributed to sitosterol which is one of the plant-derived sterols. A very important argument indicating the necessity of a varied diet rich in a variety of plant products is the beneficial effect of polyphenols, which are most abundant in multicolored vegetables and fruits. Numerous studies show their effectiveness in lowering blood pressure, improving lipid profile, and regeneration of vascular endothelium. The collected publications from the field of lifestyle medicine can be a source of knowledge for dieticians, physicians, and people associated with physical culture and human mental health to prevent the development of cardiovascular diseases and reduce the risk of death from this cause.

Multicentre early experience with totally subcutaneous cardioverter-defibrillators in Poland.

INTRODUCTION: Implantable cardioverter-defibrillators (ICD) have a strong position in the prevention of sudden death. Nowadays, the most commonly used high-energy cardiac devices are transvenous ICDs. A new technology of totally subcutaneous ICDs (S-ICD) was invented and recently introduced into clinical practice in order to reduce lead-related complications of conventional ICDs. The aim of this paper is to present early experience with this new technology implemented in a few centres in Poland. MATERIAL AND METHODS: Medical records of patients who had S-ICD-related interventions in Poland were retrospectively analysed. RESULTS: During the first year of S-ICD introduction into the Polish health system 18 patients underwent surgery connected with S-ICDs. Majority of them (17 patients) were implanted de novo. In one patient surgical revision of a device implanted abroad was performed. Most of patients (78%) had S-ICDs implanted for secondary prevention. Inability of transvenous system implantation due to venous access obstruction or high risk of infection related with transvenous leads accounted for 83% of indications for S-ICD. Only in three patients were S-ICDs implanted due to young age and active mode of life. The implantations of S-ICDs were performed without important early or late complications. During follow-up one patient had episodes of ventricular arrhythmia successfully terminated with high-energy shocks. One patient died due to progression of heart failure. CONCLUSIONS: S-ICD implantation procedure has been successfully and safely introduced in Polish clinical routine. Nevertheless, despite clear indications in recent ESC guidelines, this therapy is not directly reimbursed in Poland and needs individual application for refund.

Patients with cardiac implantable electronic devices undergoing radiotherapy in Poland. Expert opinion of the Heart Rhythm Section of the Polish Cardiac Society and the Polish Society of Radiation Oncology.

Older age and high morbidity of the society contribute to a growing number of patients with cardiac implantable electronic devices (CIEDs) requiring effective cancer treatment, including radiotherapy (RT). The effect of RT on a CIED may vary depending on the type and physical parameters of radiation, location of the treated lesion, indications for electrotherapy, and the type of CIED. In the most dramatic scenarios, it may cause an irreversible damage to the CIED, with serious clinical consequences. The lack of precise guidelines may limit the access to RT for many patients with CIEDs who would otherwise benefit from the therapy or may lead to a therapy without taking the necessary precautions, which may worsen the prognosis. Therefore, clear and unequivocal recommendations for assessing patient eligibility for RT are aimed at ensuring that adequate precautions are taken as well as at providing patients with concomitant cardiovascular and oncologic diseases with access to safe and effective RT.

Ferritin as a potential biomarker of efficacy of treatment of atrial fibrillation - preliminary report.

BACKGROUND: Complex mechanisms of responsible for originating and maintaining of atrial fibrillation (AF) are involved in pathophysiology of this arrhythmia. Inflammation substantially contribute to arrhythmic remodelling of atrial tissue.The aim of the present study is to assess an applicability of ferritin and high sensitive C-reactive protein (hs-CRP) as biomarkers of atrial fibrillation and their usefulness in evaluation of efficacy of cryoablation. MATERIALS AND METHODS: The study population consisted of 40 patients who underwent first AF cryoablation procedure. The whole follow-up time was for 6 months. The efficacy of cryoablation was defined as lack of episodes of AF longer than 30 s reported either in patient's medical documentation or present in standard or Holter ECG records. Concentrations of hs-CRP (latex method ) and ferritin (immunochemical method) were determined in standard way in hospital laboratory. RESULTS: The recurrence of atrial fibrillation during follow-up was detected in 7 of 40 patients (efficacy 82.5%). Basal concentrations of hs-CRP and ferritin were significantly higher in patients who underwent ablation during AF. Ablation resulted in an increase of either hs-CRP or ferritin concentrations. After seven days, both hs-CRP and ferritin concentrations returned to basal level. The trend toward the higher concentration of hs-CRP was observed in AF recurrence subgroup in 30th and the 90th day after the procedure. Ferritin concentrations were significantly higher in recurrence subgroup after 30 and 90 days. CONCLUSION: Our results suggest that the evaluation of ferritin serum level can be a potential tool for assessment of AF treatment efficacy.

Trying to predict the unpredictable: Variations in device-based daily monitored diagnostic parameters can predict malignant arrhythmic events in patients undergoing cardiac resynchronization therapy.

BACKGROUND: The aim of this study was to evaluate the value of device-based diagnostic parameters in predicting ventricular arrhythmias in cardiac resynchronization therapy (CRT) recipients. METHODS: Ninety-six CRT-D patients participating in TRUST CRT Trial were analyzed. The inclusion criteria were: heart failure in NYHA ≥ 3 class, QRS ≥ 120 ms, LVEF £ 35% and significant mechanical dyssynchrony. Patients were divided into those with (n = 31, 92 arrhythmias) and without (n = 65) appropriate ICD interventions within follow-up of 12.03 ± 6.7 months. Daily monitored device-based parameters: heart rate (HR), thoracic impedance (TI), HR variability and physical activity were analyzed in 4 time windows: within 10, 7, 3 days and 1 day before appropriate ICD interventions. RESULTS: A consistent pattern of changes in three monitored factors was observed prior to arrhythmia: 1) a gradual increase of day HR (from 103.43% of reference within 10-day window to 105.55% one day before, all p < 0.05 vs. reference); 2) variations in night HR (104.75% in 3 days, 107.65% one day before, all p < 0.05) and 3) TI decrease (from 97.8% in 10 days to 96.81% one day before, all p < 0.05). The combination of three parameters had better predictive value, which improved further after exclusion of patients with atrial fibrillation (AF). The predictive model combining HR and TI together with LVEF and NT-proBNP was more prognostic than the model involving LVEF and NT-proBNP alone (difference in AUC 0.05, 95% CI 0.0005-0.09, p = 0.04). CONCLUSIONS: Daily device-monitored parameters show significant variations prior to ventricular arrhythmia. Combination of multiple parameters improves arrhythmia predictive performance by its additive value to baseline risk factors, while presence of AF diminishes it.

Bridge to recovery in two cases of dilated cardiomyopathy after long-term mechanical circulatory support.

Ventricular assist devices (VADs) have become an established therapeutic option for patients with end-stage heart failure. Achieving the potential for recovery of native heart function using VADs is an established form of treatment in a selected group of patients with HF. We report two cases of VAD patients with different types of pump used for mechanical circulatory support, a continuous flow pump (Heart-Ware(®)) and a pulsatile pump (POLVAD MEV(®)), which allow regeneration of the native heart. Patients were qualified as INTERMACS level 3-4 for elective implantation of an LVAD. Implantations were performed without complications. The postoperative course was uncomplicated. In the HeartWare patient the follow-up was complicated by episodes of epistaxis and recurrent GIB as well as driveline infection. The follow-up of the POLVAD MEV patient was uneventful. Recurrent GIB forced us to withdraw aspirin and warfarin therapy and maintain only clopidogrel in the HeartWare patient.. In mid-February 2013 the patient was admitted due to dysfunction of the centrifugal pump with a continuous low-flow alarm and increase power consumption. Under close monitoring of the patient a decision was made to stop the pump immediately and evaluate cardiac function. The serial echocardiography studies showed significant improvement in LVEF up to 45% and no significant valvular pathology. In February 2013 LVAD explant was performed by left thoracotomy without complications. At six-month follow-up the patient was in a good clinical condition, in NYHA class I/II, and on pharmacological treatment.

European experience of the convergent atrial fibrillation procedure: multicenter outcomes in consecutive patients.

BACKGROUND: The objective of this collaborative, multicenter, European effort was to evaluate the outcomes of the convergent procedure for the treatment of persistent and long-standing persistent atrial fibrillation (AF) in consecutive patients at 4 European centers. METHODS: Outcomes of consecutive patients, undergoing the convergent procedure at 4 European centers, were evaluated in this study. Epicardial ablation was performed before endocardial ablation. Convergent procedure outcomes were recorded by interrogation of implanted loop recorders or Holter monitors. Rhythm status and required interventions (antiarrhythmic drugs, cardioversions, and repeat ablations) were quantified 6 and 12 months after the procedure. Outcomes, monitoring type, and patient baseline characteristics were analyzed and reported. RESULTS: Seventy-three consecutive patients presenting with persistent AF (30.1%) or long-standing persistent AF (69.9%) underwent the convergent procedure between January 2010 and December 2011. At 6 months, 82% (56/68) were in sinus rhythm. At 12 months, 80% (53/66) were in sinus rhythm; single-procedure maintenance of sinus rhythm without postblanking period interventions was 76% (50/66); 52% (34/66) were in sinus rhythm and not receiving antiarrhythmic drugs. CONCLUSIONS: This multicenter European collaborative effort demonstrated that the convergent procedure is a safe and efficacious treatment option for persistent and long-standing persistent AF.

Minimally invasive hybrid ablation procedure for the treatment of persistent atrial fibrillation: one year results.

BACKGROUND: The concept of a hybrid approach, combining the most effective techniques of surgical and endocardial catheter ablation has resulted in the creation of the convergent ablation procedure. This novel, pericardioscopic, hybrid approach can be an effective option for highly symptomatic patients with persistent atrial fibrillation (PSAF) and longstanding persistent atrial fibrillation (LSPAF) for whom standalone surgical or endocardial ablation procedures offer sometimes unsatisfactory outcomes. AIM: To assess the safety, efficacy and effectiveness of a hybrid epicardial and endocardial radiofrequency ablation for the treatment of PSAF and LSPAF. METHODS: Single-centre, prospective, non-randomised clinical study. Between August 2009 and December 2011, 27 patients with PSAF (n = 5) and LSPAF (n = 22) underwent hybrid ablation (HABL). Mean age was 52.52 ± 11.27 years, and the mean EHRA class was 2.5; 14 (51.8%) patients had a history of electrical cardioversion (n = 6) or catheter ablation (n = 8). Five patients had left ventricular ejection fraction (LVEF) of less than 35%. Mean AF duration for all patients was 3.46 ± 2.5 years. All patients were on antiarrhythmic drugs (AAD) and oral anticoagulation. Patients were scheduled for three, six and 12 month follow-up with seven day Holters, REVEAL® XT and ECHO measurements. RESULTS: The HABL procedure was feasible in all patients. At six months post procedure, 72.2% (13/18) of patients were in SR, and 66.5% (12/18) were off class I/III AADs. Four patients were in AF and one patient developed right atrial flutter. At one year post procedure, 80% (8/10) of patients were in SR and off class I/III AADs. At two year post procedure, 100% (6/6) of patients were in SR and off class I/III AADs. Rapid change in left ventricular function was noted in patients with low LVEF (≤ 35%) prior to the procedure. Patients with LVEF +40% had less apparent improvement. CONCLUSIONS: Hybrid, epicardial and endocardial, radiofrequency ablation is feasible and safe, effectively restoring sinus rhythm in the vast majority of patients with PSAF and LSPAF.

Implantation feasibility, procedure-related adverse events and lead performance during 1-year follow-up in patients undergoing triple-site cardiac resynchronization therapy: a substudy of TRUST CRT randomized trial.

INTRODUCTION: This substudy was to assess implantation feasibility and long-term safety of triple-site resynchronization therapy (CRT) in a series of consecutive patients included in a randomized trial. METHODS AND RESULTS: One hundred consecutive patients enrolled into Triple-Site Versus Standard Cardiac Resynchronization Therapy Randomized Trial were analyzed. Eligibility criteria included NYHA class III-IV, sinus rhythm, QRS ≥ 120 milliseconds, left ventricular ejection fraction ≤35%, and significant mechanical dyssynchrony. Patients were randomized in a 1:1 ratio to conventional or triple-site CRT with defibrillator-cardioverter. After 12 months of resynchronization 30% of patients with conventional resynchronization and 12.5% with triple-site CRT were in NYHA functional class III or IV (P < 0.05). Implantation of triple-site systems was significantly longer (median 125 minutes vs 96 minutes; P < 0.001), with higher fluoroscopic exposure, especially in patients with very enlarged left ventricle or pulmonary hypertension. Implantation success-rate was similar in the triple-site and conventional group (94% vs 98%; P = NS); however, additional techniques had to be used in a greater proportion of the triple-site patients (33.3% vs 16%; P < 0.05). Long-term lead performance tests revealed significantly higher pacing threshold and lower impedance in the triple-site group. The 1-year incidence of serious, CRT-related adverse events was similar in triple-site and conventional group (20.8% vs 30%; P = NS). CONCLUSIONS: Triple-site CRT is associated with more pronounced functional improvement than standard resynchronization. This form of pacing is equally safe and feasible as the conventional CRT. However, triple-site procedure is more time-consuming, associated with higher radiation exposure and the need to use additional techniques. Triple-site resynchronization is associated with less favorable electrical lead characteristics.

Microvolt T-wave alternans and other noninvasive predictors of serious arrhythmic events in patients with an implanted cardioverter-defibrillator.

BACKGROUND: Prediction of recurrent malignant ventricular tachyarrhythmias after insertion of a implantable cardioverter-defibrillator (ICD) is challenging. Microvolt T-wave alternans (MTWA) seems to be a promising marker of such events in ICD recipients. AIM: To assess prognostic significance of MTWA and other noninvasive parameters in the prediction of major arrhythmic events after ICD implantation. METHODS: This prospective study included 155 patients (121 male, age 59 ± 11 years) in whom ICD was implanted for secondary prevention of a sudden cardiac death. In all patients, clinical evaluation along with estimation of ejection fraction, MTWA measurement using the HearTwave Cambridge Heart system, and determination of the corrected QT interval (QTc) and QT dispersion (QTd) based on resting ECG were performed 3 days before ICD implantation. Using 24-h Holter monitoring, cardiac arrhythmias, QT interval, QT dynamicity, QT variability (QTSD) and heart rate variability (HRV) time domain parameters were determined. MTWA results were categorised, based on the accepted criteria, as positive, negative or indeterminate. In further analyses, positive and indeterminate MTWA results were grouped together as abnormal or non-negative tests [MTWA+], while negative MTWA results were considered normal [MTWA-]. During the follow-up (mean duration 21.6 ± 11.6 months), major arrhythmic cardiac events (MACE), defined as death and/or the need for ablation and/or heart transplantation due to malignant ventricular tachyarrhythmias, were recorded. RESULTS: During the follow-up, MACE occurred in 17 (11%) patients. Abnormal MTWA before ICD implantation was found significantly more frequently in patients with MACE as compared to patients without MACE. Multivariate Cox regression analysis identified abnormal MTWA and QTSD as independent risk factors for MACE, with hazard ratios of 10.82 (95% CI 9.76-11.88; p〈 0.05) and 1.08 (95% CI 1.05-1.08), respectively. Significant differences in MACE-free survival rate with regard to MTWA results (abnormal vs normal MTWA) were shown during the follow-up (p〈 0.001). The negative predictive value of normal MTWA for MACE was 98.6%. When both MTWA and QTSD were combined, the positive predictive value increased to 35%, with a sensitivity of 82% and specificity of 81%. The probability of MACE with normal results of both these tests was 2.3%. CONCLUSIONS: Abnormal MTWA is a strong independent predictor of MACE in ICD recipients, and QTSD is a weaker predictor. In the prediction of MACE after ICD implantation, the highest predictive value was noted for abnormal MTWA combined with QTSD. Normal values of these two parameters were associated with a low probability of MACE. These results suggest that standardised MTWA evaluation can be useful for risk stratification in the clinical practice.

Transseptal versus transaortic approach for radiofrequency ablation in patients with cardioverter-defibrillator and electrical storm.

PURPOSE: Radiofrequency current ablation (RFCA) of ventricular tachycardia (VT) is usually performed using a retrograde transaortic approach. We compared the mapping accuracy, procedural course, safety, and results of VT ablation using transseptal and transaortic route. METHODS: Twenty-one consecutive patients with ischemic cardiomyopathy and history of electrical storm underwent RFCA with electro-anatomic mapping system. In six patients, ablation was performed with transseptal approach (transseptal group); in 15, retrograde approach to the left ventricle was used (retrograde group). RESULTS: The endocardial surface of the left ventricle was similarly accessible in both methods. Less detailed maps of interventricular septum were constructed with the use of transseptal approach. The RFCA success rate was similar in the transseptal and retrograde groups (83 vs. 80%, p = NS). The median procedural time was 112 min in transseptal vs. 145 min in the retrograde group; radiation exposure was 200 vs. 67 mGy, respectively (both p < 0.05), and fluoroscopy time was 22 vs.16 min (p = NS). During the 3-month follow-up, VT recurrence occurred in one patient in the transseptal group and in three patients in the retrograde group (p = NS). CONCLUSIONS: Transseptal approach is an accurate, safe, feasible, and effective method of RF ablation in patients with malignant, recurrent ventricular arrhythmias. However, limited access to the septal regions with the use of this method has to be remembered. Transseptal approach may be considered as an alternative to the transaortic route in patients with contraindication to the latter.

Immediate ventricular tachycardia after abnormal microvolt T-wave alternans.

Microvolt T-wave alternans (MTWA) is a promising non-invasive method of evaluating repolarization abnormalities. Its presence is strongly related to the occurrence of malignant ventricular tachyarrhythmias and is therefore regarded as a risk marker for sudden cardiac death. Most recent studies have described the usefulness of MTWA in selecting patients who may benefit from a cardioverter-defibrillator. This study presents two cases of patients suffering from ischemic cardiomyopathy, who underwent an MTWA test. Episodes of ventricular tachycardia occurred immediately after the end of the tests, with abnormal results.

Risk stratification according to the type of impaired renal function in patients with acute myocardial infarction treated with percutaneous coronary intervention.

BACKGROUND: It has been shown that successful reperfusion improves in-hospital and long-term outcome of patients with acute myocardial infarction (AMI). Nevertheless, some patients are still at high risk due to AMI despite achievement of reperfusion. Impaired renal function (IRF) is one of the recently recognised risk factors in this population. However, the prognostic value of different types of IRF in patients with AMI treated with percutaneous coronary intervention (PCI) has not been well characterised. AIM: To evaluate the prognostic value of different types of IRF in AMI patients treated with PCI. METHODS: The single centre AMI registry encompassed 1486 consecutive AMI patients treated with PCI, who were followed for a mean of 29.7 months. Subjects with at least 1 measurement of serum creatinine >133 micromol/l (>1.5 mg/dl) during hospitalisation were selected (n=194; 13.1%) and incorporated into the IRF group. The control group consisted of 1292 (86.9%) subjects with normal renal function. The IRF patients were divided into subgroups: contrast-induced nephropathy--CIN (n=90; 6.1%); and chronic kidney disease--CKD (n=66; 4.4%). Thirty-eight patients from the IRF group (2.6%) had normal value of serum creatinine on admission and did not match criteria of CIN. Patients with creatinine value >133 micromol/l on admission were incorporated into the CKD group. CIN was defined as a serum creatinine level <134 micromol/l on admission and a 25% increase of that parameter, with a value >133 micromol/l within 48 hours after PCI. Among CIN patients 2 subgroups were identified with respect to coexisting diabetes mellitus: CIN-DM and CIN-nDM (both n=45; 3.05%). RESULTS: Remote mortality rate was significantly higher in the IRF group (38.7%) and in particular subgroups--CKD (51.5%), CIN-DM (46.7%), CIN-nDM (28.9%)--than in controls (10.3%, p <0.001 for all study groups vs. controls). Multivariate analysis identified IRF as an independent predictor of any-cause death in the whole population [hazard ratio (HR) 2.23; 95% CI 1.99-2.47, p <0.001]. All defined types of IRF had a significant and independent influence on remote survival in the study population (CIN-DM - HR 3.52; 95% CI 3.23-3.81; CIN-nDM--HR 2.60; 95% CI 2.29-2.91; CKD--HR 1.98; 95% CI 1.68-2.28). CONCLUSIONS: Impaired renal function and all defined types of renal impairment have been shown to worsen the long-term prognosis of AMI patients treated with PCI. The most important risk factor of mortality is CIN in diabetic patients, which is associated with an over 3.5-fold increase of death hazard in this study population.

Different types of renal dysfunction in patients with acute myocardial infarction treated with percutaneous coronary intervention.

BACKGROUND: The prognostic significance of different types of renal dysfunction in patients with acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI) has not been well characterized. METHODS: The single-center AMI registry encompassed 1,486 consecutive AMI patients treated with PCI, who were followed by mean 29.7 months. Subjects with an estimated glomerular filtration rate <60 mL/min per 1.73 m2 at baseline were selected (n = 283, 19.0%) and incorporated into the chronic kidney disease (CKD) group. The control group consisted of 1,203 subjects with normal renal function (81.0%). The CKD patients were divided into subgroups: with contrast-induced nephropathy - CKD + CIN (n = 68, 4.6%) and without - CKD-CIN (n = 215, 14.5%). RESULTS: Remote mortality rate was significantly higher in CKD group (34.6%) and in particular subgroups: CKD + CIN (47.0%), CKD-CIN (31.0%) than in controls (9.1%, P < 0.001 for all study groups vs controls). Multivariate analysis identified CKD as an independent predictor of any-cause death in the whole population (hazard ratio [HR] 1.77, 95% confidence interval [CI] 1.60-1.94, P < 0.001). Similarly, CKD + CIN contrary to CKD-CIN had significant and independent influence on remote survival in study population (HR 2.16, 95% CI 1.95-2.37, P < 0.001). CONCLUSIONS: CKD and its types have significant, negative influence on long-term survival in AMI patients treated with PCI. It is especially strongly expressed in those CKD patients who develop contrast-induced nephropathy, which occurrence is an independent risk factor of mortality associated with over twofold increase of death hazard.

Electrophysiologic parameters suggesting significant acute cellular rejection of the transplanted heart.

AIM OF THE STUDY: Was to estimate an influence of acute cellular rejection on electrophysiologic parameters of allograft and remnants of recipient's heart, in patients after orthotopic heart transplantation (OHT). PATIENTS AND METHODS: Analysis was performed in 25 OHT recipients (24M/1F, age 48.4 +/- 9 y., ischemic time 197 +/- 51 min., donor age 30 +/- 9 y.), who underwent electrophysiological study (EPS), along with elective endomyocardial biopsy (EMB), scheduled for the 1st month after the surgery. Results of EPS were correlated with a degree of rejection, assessed with the ISHLT grading system. Grades > or =3A were considered a significant cellular rejection. RESULTS: ISHLT grade 0 was observed in 8 patients, grade 1A or 1B in 12 patients, and 3A in 5 patients. Frequency of transplanted heart rhythm (TH-R) was 691.3+/- 37 ms in patients with ISHLT grade 0, 690.4 +/- 41 ms in patients with grade 1A or 1B, and 744.4 +/- 668 ms in individuals with 3A rejection (p < 0.04, for difference between 0 and 3A groups). Intraatrial conduction time (IntrtaCT) was significantly shorter in grade 3A group (20.4 +/- 1.6 ms), when compared with patients without rejection (36.2 +/- 4.9 ms, p < 0.03), or with 1A or 1B rejection (41.5 +/- 13 ms, p < 0.032). Also interatrial conduction time (InterCT) was the shortest in patients with 3A rejection (53.8 +/- 4.3 ms), when compared with ISHLT grade 0 group (78.5 +/- 7.6 ms, p < 0.02) and 1A/1B group (74.1 +/- 12 ms, p < 0.023). The other characteristics of atria, ventricles and AV-junction performance were comparable in all patients. CONCLUSIONS: TH-R, IntraCT and InterCT should be considered as the markers of significant cellular rejection in patients after OHT. Further analysis involving higher number of patients is warranted.

Use of the LocaLisa mapping system during ablation procedures in patients with atrioventricular nodal reentrant tachycardia.

INTRODUCTION: LocaLisa is a novel system for anatomical mapping. It enables an assessment of the three-dimensional position of electrodes within cardiac chambers without fluoroscopy. With this technique it may be possible to reduce radiation exposure during catheter-based ablation procedures. AIM: To evaluate the efficacy and safety of ablation procedures performed using the LocaLisa mapping system in patients with atrioventricular nodal reentrant tachycardia (AVNRT). METHODOLOGY: This study evaluated the course of the first 26 ablations performed using the LocaLisa system (studied group). The control group involved 30 consecutive patients with AVNRT treated with the conventional ablation technique that was routinely used prior to the introduction of the novel system into clinical practice. RESULTS: In the studied group procedural duration was 72.4+/-24.9 minutes, in the control group 80.1+/-18.2 minutes (NS). However, radiation exposure was significantly lower in the examined group -- 74.4+/-109.2 mGy compared to 184.8+/-59.9 mGy in the control group (p <0.05). All procedures were successful. No complications related to the ablation were observed. CONCLUSIONS: Employment of the LocaLisa mapping system enables the reduction of fluoroscopic exposure without any decrease of efficacy or elevation of risk of any complications during AVNRT ablations.

Radio-frequency ablation of arrhythmias following congenital heart surgery.

BACKGROUND: Cardiac arrhythmias as a late complication following congenital heart surgery are encountered more and more frequently in clinical practice. The use of new electrophysiological methods of visualisation and mapping improves the efficacy of radio-frequency (RF) ablation of these arrhythmias. AIM: To assess patterns of atrial arrhythmias following congenital heart surgery and to examine the efficacy of RF ablation using the electro-anatomical CARTO system. METHODS: Electrophysiological diagnostic study and RF ablation were performed in 24 consecutive patients (mean age 36+/-18 years) who had atrial arrhythmias following congenital heart surgery. The mechanism of arrhythmia (ectopic or reentrant) and strategy of RF ablation procedure were based on the results of the right atrial map performed during index arrhythmia. RESULTS: The patients were divided into five groups according to the type of congenital heart surgery. The ASD group consisted of 17 patients who had undergone in the past surgery due to atrial septal defect, four patients had a history of surgery due to ventricular septal defect (VSD group), and one patient each had undergone surgery due to corrected transposition of the great arteries (ccTGA), tetralogy of Fallot (TF) or dual-outflow right ventricle (DORV). During diagnostic electrophysiological study typical atrial flutter (AFL) was diagnosed in nine patients from the ASD group, atypical AFL in three ASD patients, and ectopic atrial tachycardia (EAT) in six ASD patients. In one patient EAT was induced after ablation of typical AFL. Of the VSD patients, three had atypical AFL, and one had typical AFL. The patient following surgery for ccTGA had atypical AFL and EAT, whereas in the two remaining patients (DORV and TF) atypical AFL was demonstrated. The efficacy of the first session of RF ablation was 83% and no complications were observed. The efficacy of RF ablation of typical AFL was 90%, atypical AFL 78%, and EAT 86% (NS). During the long-term follow-up (24+/-17 months) arrhythmia recurrences were noted in 2 (10%) out of 20 patients who were effectively treated during the first RF ablation session. CONCLUSIONS: Reentry is the most common electrophysiological mechanism of incisional tachycardias, followed by ectopic atrial tachycardia. RF ablation using the electro-anatomical CARTO system is effective and safe in this group of patients.