Xavier Viñolas

Interatrial blocks. A separate entity from left atrial enlargement: a consensus report

Impaired interatrial conduction or interatrial block is well documented but is not described as an individual electrocardiographic (ECG) pattern in most of ECG books, although the term atrial abnormalities to encompass both concepts, left atrial enlargement (LAE) and interatrial block, has been coined. In fact, LAE and interatrial block are often associated, similarly to what happens with ventricular enlargement and ventricular block. The interatrial blocks, that is, the presence of delay of conduction between the right and left atria, are the most frequent atrial blocks. These may be of first degree (P-wave duration >120 milliseconds), third degree (longer P wave with biphasic [±] morphology in inferior leads), and second degree when these patterns appear transiently in the same ECG recording (atrial aberrancy). There are evidences that these electrocardiographic P-wave patterns are due to a block because they may (a) appear transiently, (b) be without associated atrial enlargement, and (c) may be reproduced experimentally. The presence of interatrial blocks may be seen in the absence of atrial enlargement but often are present in case of LAE. The most important clinical implications of interatrial block are the following: (a) the first degree interatrial blocks are very common, and their relation with atrial fibrillation and an increased risk for global and cardiovascular mortality has been demonstrated; (b) the third degree interatrial blocks are less frequent but are strong markers of LAE and paroxysmal supraventricular tachyarrhythmias. Their presence has been considered a true arrhythmological syndrome.

Catheter ablation vs. antiarrhythmic drug treatment of persistent atrial fibrillation: a multicentre, randomized, controlled trial (SARA study)

Background Catheter ablation (CA) is a highly effective therapy for the treatment of paroxysmal atrial fibrillation (AF) when compared with antiarrhythmic drug therapy (ADT). No randomized studies have compared the two strategies in persistent AF. The present randomized trial aimed to compare the effectiveness of CA vs. ADT in treating persistent AF. Methods and results Patients with persistent AF were randomly assigned to CA or ADT (excluding patients with long-standing persistent AF). Primary endpoint at 12-month follow-up was defined as any episode of AF or atrial flutter lasting >24 h that occurred after a 3-month blanking period. Secondary endpoints were any atrial tachyarrhythmia lasting >30 s, hospitalization, and electrical cardioversion. In total, 146 patients were included (aged 55 ± 9 years, 77% male). The ADT group received class Ic (43.8%) or class III drugs (56.3%). In an intention-to-treat analysis, 69 of 98 patients (70.4%) in the CA group and 21 of 48 patients (43.7%) in the ADT group were free of the primary endpoint (P = 0.002), implying an absolute risk difference of 26.6% (95% CI 10.0–43.3) in favour of CA. The proportion of patients free of any recurrence (>30 s) was higher in the CA group than in the ADT group (60.2 vs. 29.2%; P < 0.001) and cardioversion was less frequent (34.7 vs. 50%, respectively; P = 0.018). Conclusion Catheter ablation is superior to medical therapy for the maintenance of sinus rhythm in patients with persistent AF at 12-month follow-up. Clinical Trial Registration Information NCT00863213 (http://clinicaltrials.gov/ct2/show/NCT00863213).

Automatic measurement of corrected QT interval in Holter recordings: Comparison of its dynamic behavior in patients after myocardial infarction with and without life-threatening arrhythmias

This study was designed to determine the value of automatic corrected QT-interval measurement in Holter tapes in patients after myocardial infarction as a marker of life-threatening ventricular arrhythmias. We compared the corrected QT interval, automatically measured in 24-hour Holter recordings, in two groups of patients after myocardial infarction: group I was composed of 14 patients admitted consecutively to our hospital for documented sustained ventricular tachycardia or out-of-hospital cardiac arrest. Group II consisted of 28 patients with previous myocardial infarction with characteristics similar to those of group I, but without malignant ventricular arrhythmias in the follow-up. The global mean 24-hour corrected QT interval was longer in group I (425 +/- 20 msec) than in those patients after myocardial infarction without arrhythmias (group II) (405 +/- 17 msec; p < 0.01). Furthermore, a significant proportion of patients of group I (seven of 14) exhibited more peaks of corrected QT longer than 500 msec compared with patients of group II (two of 28; p < 0.005). A circadian rhythm of corrected QT peaks was observed in group I, having a significantly higher incidence from 11 PM to 11 AM (p < 0.05). We conclude that automatic corrected QT-interval measurement on Holter electrocardiogram is now available and feasible. Our results suggest that this is a marker for risk assessment of life-threatening ventricular arrhythmias. Large-scale trials are needed to confirm these results and to determine the predictive value of this technique for risk stratification.

Perfil clínico de los pacientes con fibrilación auricular persistente remitidos a cardioversión: Registro sobre la cardioversión en España (REVERSE)

Los objetivos fueron conocer el manejo y las caracteristicas clinicas de los pacientes remitidos a cardioversion en Espana y compararlos con los de los estudios AFFIRM y RACE. Se registro prospectiva y consecutivamente a 1.515 pacientes con fibrilacion auricular persistente remitidos a cardioversion en 96 hospitales espanoles. La mitad recibia tratamiento con antiarritmicos de los grupos I o III de Vaughan-Williams. La estrategia de anticoagulacion con dicumarinicos 3-4 semanas antes y despues de la cardioversion fue la mas utilizada. Nuestros pacientes eran mas jovenes que los de AFFIRM y RACE. Respecto al AFFIRM, tenian menor prevalencia de embolias previas, cardiopatia isquemica, hipertension, diabetes y disfuncion sistolica. Respecto al RACE, tenian menor prevalencia de cardiopatia isquemica y embolias previas, pero algo mayor de hipertension y diabetes. Concluimos que los pacientes remitidos a cardioversion en Espana tienen un perfil de menor riesgo cardiovascular que los del AFFIRM y aparentemente menor que los del RACE.

Distinct left bundle branch block pattern in ischemic and non-ischemic dilated cardiomyopathy

A high percentage of patients with dilated cardiomyopathy have the electrocardiographic (ECG) pattern of advanced left bundle branch block (LBBB). In the present study we sought to investigate whether patients with dilated cardiomyopathy of ischemic or non‐ischemic etiology can be differentiated on the basis of LBBB pattern.

New Oral Anticoagulants vs Vitamin K Antagonists: Benefits for Health-Related Quality of Life in Patients with Atrial Fibrillation

New oral anticoagulants (NOAC) have demonstrated their efficacy as an alternative to vitamin K antagonists (VKA) in the prophylaxis of cardioembolic events in patients with atrial fibrillation (AF). However, evidence on the benefits of NOAC in health-related quality of life (HRQoL) is lacking.We evaluated changes in HRQoL related to oral anticoagulation therapy employing a specific questionnaire in a cohort of 416 patients with AF undergoing electrical cardioversion. In terms of HRQoL, we observed a progressive adaptation to treatment with VKA; satisfaction with NOAC remained constant. Older age, higher left ventricular ejection fraction and NOAC were associated with better HRQoL.

Preexcitación intermitente tras administración de adenosina

:Se describe un caso de aparicion de preexcitacion intermitente 2:1 tras administracion de adenosina en una paciente con una via accesoria que no demostraba preexcitacion en el ECG. Se revisan los mecanismos que explicarian este hecho y la posible utilidad de la adenosina para poner de manifiesto vias accesorias que no presentan preexcitacion en el ECG.

Clinical Profile and Incidence of Ventricular Arrhythmia in Patients Undergoing Defibrillator Generator Replacement in Spain

INTRODUCTION AND OBJECTIVES Implantable cardioverter-defibrillators reduce mortality in some patients with heart disease. Battery replacement is a frequent occurrence in clinical practice and is required in up to 30% of implants. The benefit/risk ratio of defibrillators varies over time and should be reevaluated at the time of replacement. The aim of this study was to determine the clinical characteristics and incidence of defibrillator therapies in patients who underwent generator replacement. METHODS This multicenter retrospective study involved patients from the UMBRELLA national registry who underwent replacement due to defibrillator battery depletion. The incidence of ventricular arrhythmias was determined via remote monitoring. Risk factors for sustained ventricular arrhythmia after replacement were analyzed. RESULTS A total of 354 patients were included (mean age [standard deviation], 61.8 [14.5] years; men, 80%; secondary prevention, 42%; ventricular arrhythmias in the explanted generator, 62%). After a 25-month follow-up, 70 patients (20%) received appropriate therapies and 8 (2.3%) received inappropriate discharges. Male sex, structural heart disease, heart failure, and the absence of resynchronization were independent predictors of ventricular arrhythmia occurrence. CONCLUSIONS One-fifth of patients had appropriate defibrillator therapies in the first 2 years after generator replacement. Determination of the factors associated with arrhythmia occurrence after replacement may be useful to optimize implantable cardioverter-defibrillator treatment.

Trends in the use of electrical cardioversion for atrial fibrillation: influence of major trials and guidelines on clinical practice.

BackgroundThe purpose of the present study was to assess the trends in the use of ECV following published studies that had compared rhythm and rate control strategies on atrial fibrillation (AF), and the recommendations included in the current clinical practice guidelines.MethodsThe REVERCAT is a population-based assessment of the use of electrical cardioversion (ECV) in treating persistent AF in Catalonia (Spain). The initial survey was conducted in 2003 and the follow-up in 2010.ResultsWe observed a decrease of 9% in the absolute numbers of ECV performed (436 in 2003 vs. 397 in 2010). This is equivalent to 27% when considering population increases over this period. The patients treated with ECV in 2010 were younger, had a lower prevalence of previous embolism, a higher prevalence of diabetes, and increased body weight. Underlying heart disease factors indicated, in 2010, a higher proportion of NYHA ≥ II and left ventricular ejection fraction <30%. We observed a reduction in the number of ECV performed in 16 of the 27 (67%) participating hospitals. However, there was an increase of 14% in the number of procedures performed in tertiary hospitals, and was related to the increasing use of ECV as a bridge to AF ablation. Considering the initial number of patients treated with ECV, the rate of sinus rhythm at 3 months was almost unchanged (58% in 2003 vs. 57% in 2010; p = 0.9) despite the greater use of biphasic energy in 2010 and a similar prescription of anti-arrhythmic drugs.ConclusionsAlthough we observed a decrease in the number of ECVs performed over the 7 year period between the two studies, this technique remains a common option for treating patients with persistent AF. The change in the characteristics of candidate patients did not translate into better outcomes.

La arritmología como una especialidad dentro de la cardiología: sistema de acreditación en electrofisiología cardiaca intervencionista de la Sección de Electrofisiología y Arritmias de la Sociedad Española de Cardiología

La electrofisiologia cardiaca se esta desarrollando rapidamente como una subespecialidad dentro de la cardiologia que requiere formacion y entrenamiento adicionales. Por ello, es necesario promover y garantizar una capacitacion y una cualificacion de sus profesionales suficientes y homogeneas, que deben ser reconocidas o acreditadas como elementos de informacion para administraciones sanitarias, profesionales y usuarios. Este documento, desarrollado por la Seccion de Electrofisiologia y Arritmias de la Sociedad Espanola de Cardiologia, presenta un sistema especifico de acreditacion en electrofisiologia cardiaca para profesionales y centros de formacion. Para ser acreditado, el profesional debe ser especialista en cardiologia, haber recibido formacion especifica durante al menos 1 ano en un centro acreditado para ello y superar una prueba teorica de excelencia. Por su parte, el centro acreditado para la formacion debe estar encuadrado dentro de un servicio de cardiologia con una minima capacitacion asistencial, docente e investigadora, que se detalla en este documento.