Catheter Ablation of Atrial Fibrillation

Catheter ablation of atrial fibrillation (AF) has become a viable therapeutic alternative in symptomatic patients resistant to antiarrhythmic drugs. Since the first report of catheter ablation a decade ago, several techniques have evolved. These techniques reflect principal mechanisms of AF. Besides segmental electrical isolation, circumferential ablation around the pulmonary venous ostia with a support of the 3D electroanatomical mapping system appears to be the most frequently used techniques. Some authors use various combinations of these techniques including guidance with intracardiac echocardiography (ICE). Most recently, ablation within areas of fractionated electrograms during AF has been proposed. The aim of this review is to summarize briefly current techniques, their efficacy and safety

Clinical predictors of outcome in survivors of out-of-hospital cardiac arrest treated with hypothermia

AbstractBackgroundOut-of-hospital cardiac arrest (OHCA) is a leading cause of death and severe neurological disability. The objective of this study was to identify clinical predictors of early neurological outcome in survivors of OHCA managed according to recent recommendations for OHCA care.MethodsData from survivors of OHCA, admitted to a tertiary cardiac intensive care unit and treated with hypothermia in a 22 months period (n=46, age 60±13 years, 74% males) were retrospectively evaluated. At 1-month follow-up, patients were classified according to the best achieved Glasgow–Pittsburgh cerebral performance categories (CPC 1–5) and factors affecting the outcome were analysed.ResultsAt 1-month follow-up, 23 patients (50%) had favourable outcome (CPC 1–2), while 23 patients (50%) had poor outcome (CPC 3–5), including 19 with in-hospital death (41% of total). Patients with good outcome were younger (55±13 years vs. 66±10 years; P=0.003), had more often myocardial infarction as the cause of arrest (63% vs. 30%; P=0.018) and ventricular fibrillation/tachycardia as an initial rhythm (78% vs. 39%; P=0.007). Both groups differed by lactate level on admission (4.0±4.6 vs. 7.3±4.1mmol/l, P=0.02), after 12h (2.5±1.1 vs. 4.3±3.2mmol/l, P=0.04) and after 24h (1.9±1.2 vs. 3.2±1.9mmol/l, P=0.04). Logistic regression revealed the following independent outcome predictors: age, acute myocardial infarction and admission lactate level.ConclusionFavourable outcome was observed in a half of OHCA survivors. Young age, acute myocardial infarction as underlying aetiology of cardiac arrest, and low lactate level on admission were the best predictors of favourable outcome

Catheter Ablation of Ventricular Tachycardia

Catheter ablation is highly successful and may be considered as the first line treatment in all symptomatic idiopathic forms of ventricular tachycardia (VT). Also ablation plays an important role in recurrent VTs associated with structural heart disease and relatively preserved left ventricular ejection fraction (>35%) and/or bundle branch reentry VT. It also constitutes the preferable treatment modality in incessant VTs of any origin and in patients with implantable defibrillator (ICD) devices who present with recurrent VTs and/or an electrical storm leading to multiple ICD shocks Catheter ablation appears to improve arrhythmia control in about two thirds of patients with structural heart disease and mappable VTs. Novel substrate and/or noncontact mapping techniques suggest that even hemodynamically unstable VTs and/or VTs of multiple morphologies can be successfully ablated. As the ablation method is not curative and there remains the risk of dying suddenly in patients with depressed left ventricular ejection fraction, the majority of patients with VT associated with structural heart disease also receive an ICD

The role of imaging to support catheter ablation of atrial fibrillation

AbstractAtrial fibrillation (AF) ablation is a complex procedure that requires transseptal puncture and extensive manipulation with catheter(s) in the left atrium and pulmonary veins. Individual anatomy of these structures contributes to a challenge of AF ablation. The proximity of surrounding structures, such as esophagus, further increases risk of complications of this procedure. Increased risk of intracardiac thrombosis associated with AF is another factor that may complicate management of these patients. For all these reasons, imaging techniques play increasingly important role. Preprocedural imaging becomes important not only to rule out thrombus but also for assessment of anatomy of the PVs and left atrium, left atrial size and the extent of a substrate. Various forms of imaging help significantly during the procedure both with identification of anatomy and with catheter navigation. Many studies have shown increased efficacy, safety and decreased fluoroscopy times. After the procedure, imaging techniques such as echocardiography, CT or MR imaging are useful to diagnose potential complications. This paper briefly reviews clinical utility of different imaging tools for ablation of AF

801-4 Prognostic Implications of QT and QU Interval Measures in Acute Myocardial Infarction

Prolongation of the QT interval corrected using Bazett's formula (QTc) has been reported as a marker for increased risk of arrhythmic events after acute myocardial infarction (AMI). However, the QU interval changes have not been examined. At the same time, QU interval may be of clinical significance, especially in the light of recent experimental evidence linking the U wave with the subpopulation of the so-called M cells within myocardial wall. To evaluate prognostic significance of QT and QU interval measures in AMI, we studied 512 survivors of acute phase of their first myocardial infarction. Patients with conduction defects and drugs likely to affect QT measures were noT included into the analysis. The following intervals were estimated in all the measurable leads on a standard predischarge 12-lead ECG (25 mm/sec paper speed) using a digitizing pad—mean RR, mean and max QT, and mean QU. All QT and QU intervals were subsequently corrected for heart rate using Bazett's formula. At one year follow-up, 23 patients (Group I. 19 male. mean age 58.7±8.9 years) suffered arrhythmic events (VT/VF or sudden cardiac death). This subset of patients was compared with arrhythmia-free group of 489 subjects (Group II, 385 male, mean age 56.1±9.2 years). Statistical analysis was performed using unpaired t-test and ANOVA, results are expressed as mean±SD.GroupQT meanQTc meanQT maxQTc maxQU meanQUc meanI358.7±31.5426.6±30.7396.5±38.5472.8±40.3459.5±58.7535.2±41.3II387.3±44.1423.9±24421.7±51.5467.9±79.1552.0±73.9585.7±55.1p<0.002NS0.02NS0.0010.01The significant difference in QU and QUc, but not in QT intervals persisted even after elimination of the effect of heart rate (ANOVA: p<0.007 and 0.011, respectively).ConclusionThe differences in the QT but not QU interval measures in the 2 groups can be explained by differing heart rates. Shorter QU interval seemed to identify patients at risk of arrhythmic events after AMI. The pathophysiological basis for this finding is not clear, but could be related to differences in the subpopulation of M cells within myocardial wall

Isolated non-compaction cardiomyopathy: A review

AbstractLeft ventricular non-compaction cardiomyopathy (LVNC) is a rare disease which belongs to unclassified congenital cardiomyopathies. According to the ESC classification, LVNC is characterized by a spongy appearance of myocardium due to increased trabeculation and deep intertrabecular recesses that communicate with the left ventricle. This phenotype is thought to be caused by arrest of normal endomyocardial morphogenesis. Clinical manifestations of LVNC include heart failure, thromboembolic events, arrhythmias and/or sudden cardiac death. Progression of LVNC is highly variable and prediction of prognosis is very difficult. The aim of this paper is to provide an update about the topic of isolated LVNC

Case Report: Pulsed field ablation for epicardial right-sided accessory pathway

We present a case of a 32-year-old male with a history of palpitations and preexcitation on ECG who underwent altogether four failed catheter ablations using different approaches in the two other electrophysiology centers within two years. ECG showed overt preexcitation with a positive delta wave in lead I and negative in leads V1–V3, suggesting a right free wall accessory pathway. During the electrophysiological study, the accessory pathway was localized on the free lateral wall. However, the electrograms and mapping during atrial and ventricular pacing suggested the presence of true epicardial accessory pathway. Repeated radiofrequency energy delivery with the support of the steerable sheath and excellent contact (as assessed by intracardiac echocardiography) at the earliest ventricular activation was not successful. Therefore, the Farawave catheter (Boston Scientific, Inc) was used, and a flower configuration with the intention to cover the entire atrial attachment of the pathway during ventricular pacing was selected. Application of pulsed field resulted in interruption of accessory pathway conduction. An electrophysiological study one year later confirmed the persistent effect of ablation. This case illustrates the potential utility of pulsed field energy for the ablation of atrial insertion of the accessory pathway with an epicardial course. Such an approach can avoid epicardial mapping and access and may improve the safety of the procedure

Clinical Utility of Body Surface Potential Mapping in CRT Patients

This paper reviews the current status of the knowledge on body surface potential mapping (BSPM) and ECG imaging (ECGI) methods for patient selection, left ventricular (LV) lead positioning, and optimisation of CRT programming, to indicate the major trends and future perspectives for the application of these methods in CRT patients. A systematic literature review using PubMed, Scopus, and Web of Science was conducted to evaluate the available clinical evidence regarding the usage of BSPM and ECGI methods in CRT patients. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement was used as a basis for this review. BSPM and ECGI methods applied in CRT patients were assessed, and quantitative parameters of ventricular depolarisation delivered from BSPM and ECGI were extracted and summarised. BSPM and ECGI methods can be used in CRT in several ways, namely in predicting CRT outcome, in individualised optimisation of CRT device programming, and the guiding of LV electrode placement, however, further prospective or randomised trials are necessary to verify the utility of BSPM for routine clinical practice

Rare myxoid liposarcoma metastasis to the interventricular septum of the heart

AbstractLiposarcomas are malignant tumors of the soft tissue. Myxoid liposarcoma is the second most common subtype of these tumors in adults. It accounts for approximately 20% of all malignant soft tissue tumors [1,2]. Peak of its incidence occurs between 40 to 60 years of age with relatively indolent clinical course Matsumoto et al. (2007) [3], Cho et al. (2010) [4], Faiman et al. (2005) [5]. Typical localizations of myxoid liposarcoma comprise limbs, particularly thighs with a tendency to metastasize into extrapulmonary sites such as retroperitoneum, mediastinum, bones. Cardiac metastases are extremely rare.We present a case of a 36-year-old man with a history of recurrent myxoid liposarcoma. Primary location was in the left popliteal area. After extirpation of the tumor, metastatic tumor was subsequently revealed in the right axilla. Each surgical extirpation was followed by radiation therapy and brachytherapy. Cardiac metastasis was accidentally diagnosed with PET/CT during the staging process. The patient was asymptomatic and was admitted to our institution for further diagnostics and treatment. After confirmation of its location, the tumor was excised. Histological examination revealed myxoid liposarcoma