Usefulness of the intracardiac electrocardiogram recorded using central venous catheters on P-wave magnification.

Background: The detection of atrial electrical activity is extremely valuable in recognizing complex cardiac arrhythmias. However, P-wave detection on a surface electrocardiogram (S-ECG) can sometimes be challenging. The intracardiac electrocardiogram (IC-ECG), recorded by a central venous catheter loaded with saline solution, has proven to be a safe and effective method for amplifying atrial electrical activity.

Value of Electrocardiography to Distinguish Fabry Disease from Sarcomeric Hypertrophic Cardiomyopathy.

Fabry disease (FD) is a rare genetic disorder that leads to left ventricular hypertrophy (LVH), frequently misdiagnosed as hypertrophic cardiomyopathy (HCM). We sought to assess the value of electrocardiography for distinguishing FD from HCM. We retrospectively reviewed and compared standard electrocardiograms and echocardiograms from 26 patients with FD and LVH and 33 sarcomeric patients with HCM, matched for gender, age, and degree of LVH.

Catheter ablation of ventricular tachycardia in patients with electrical storm, with a special focus on patients with Chagas disease.

Background: There are few reports on the benefits of catheter ablation (CA) in patients with electrical storm (ES). None of these publications included patients with Chagas disease (ChD). Our aims are to analyze (1) all the cases of ES treated with CA and (2) the subgroup of patients with ChD.

Intramural Venous Ethanol Infusion for Refractory Ventricular Arrhythmias: Outcomes of a Multicenter Experience.

Objectives: The aim of this study was to assess the long-term efficacy and outcomes of retrograde venous ethanol ablation in treating ventricular arrhythmias (VAs).

Background: Retrograde coronary venous ethanol ablation (RCVEA) can be effective for radiofrequency ablation (RFA)-refractory VAs, particularly those arising in the LV summit (LVS).

Methods: Patients with drug and RFA-refractory VAs were considered for RCVEA after RF failure attempts.

Radiofrequency catheter ablation of frequent premature ventricular contractions using ARRAY multi-electrode balloon catheter.

Background: The noncontact mapping system facilitates the mapping of premature ventricular contractions (PVCs) and ventricular tachycardia (VT) using a 64-electrode expandable balloon catheter (ARRAY, St. Jude Medical). The aim of this study is to analyze the results and follow-up of the PVC ablation using this system.

The first Latin American Catheter Ablation Registry.

Aims: To assess the results of transcatheter ablation of cardiac arrhythmias in Latin America and establish the first Latin American transcatheter ablation registry.

Methods And Results: All ablation procedures performed between 1 January and 31 December 2012 were analysed retrospectively. Data were obtained on the characteristics and resources of participating centres (public or private institution, number of beds, cardiac surgery availability, type of room for the procedures, days per week assigned to electrophysiology procedures, type of fluoroscopy equipment, availability and type of electroanatomical mapping system, intracardiac echo, cryoablation, and number of electrophysiologists) and the results of 17 different ablation substrates: atrio-ventricular node reentrant tachycardia, typical atrial flutter, atypical atrial flutter, left free wall accessory pathway, right free wall accessory pathway, septal accessory pathway, right-sided focal atrial tachycardia, left-sided focal atrial tachycardia, paroxysmal atrial fibrillation, non-paroxysmal atrial fibrillation, atrio-ventricular node, premature ventricular complex, idiopathic ventricular tachycardia, post-myocardial infarction ventricular tachycardia, ventricular tachycardia in chronic chagasic cardiomyopathy, ventricular tachycardia in congenital heart disease, and ventricular tachycardias in other structural heart diseases.

Antegrade or retrograde accessory pathway conduction: who dies first?

A 36 year-old man with Wolff Parkinson White syndrome due to a left-sided accessory pathway (AP) was referred for catheter ablation. Whether abolition of antegrade and retrograde AP conduction during ablation therapy occurs simultaneously, is unclear. At the ablation procedure, radiofrequency delivery resulted in loss of preexcitation followed by a short run of orthodromic tachycardia with eccentric atrial activation, demonstrating persistence of retrograde conduction over the AP after abolition of its antegrade conduction.

Brugada electrocardiographic pattern induced by fever.

Brugada syndrome is a major cause of sudden death in young adults. Fever has been described to induce a Brugada-type electrocardiogram in asymptomatic patients with a negative family history, to disclose Brugada syndrome and to increase the risk of death and induce T wave alternans in patients with diagnosed Brugada syndrome. Risk stratification is challenging and demands a careful evaluation.

Utility of the aVL lead in the electrocardiographic diagnosis of atrioventricular node re-entrant tachycardia.

Aims: Reciprocating atrioventricular tachycardia can be categorized into common slow-fast atrioventricular node re-entrant (AVNRT) and orthodromic atrioventricular reciprocating tachycardia (AVRT). The electrocardiogram (ECG) during tachycardia is useful in distinguishing these two mechanisms. The presence of a pseudo-R'-wave in lead V1 or pseudo-S-wave in the inferior leads has been widely used, although the value of an isolated aVL lead has not been evaluated yet.

[Initiation modes of spontaneous monomorphic ventricular tachycardia in patients with Chagas heart disease].

Introduction And Objectives: We sought to demonstrate the mode of spontaneous onset of sustained monomorphic ventricular tachycardia in patients with Chagas' cardiomyopathy.

Methods: We studied 222 stored electrograms in 14 patients with Chagas cardiomyopathy and spontaneous monomorphic ventricular tachycardia treated with a cardioverter defibrillator. Premature ventricular complexes before ventricular tachycardia were classified by morphology and number.