Short-term amiodarone therapy after reversion of persistent atrial fibrillation reduces recurrences at 18 months

Background: The aim of this study was to compare the outcome of 3 months vs. 18 months of amiodarone treatment after atrial fibrillation (AF) conversion in patients who experienced the first episode of persistent AF. Methods: We included 51 patients who experienced the first episode of persistent AF receiving amiodarone (600 mg) daily for 4–6 weeks. If AF persisted, electrical cardioversion (ECV) was performed. All patients received amiodarone (200 mg daily) for 3 months and then were randomized to amiodarone (Group I) or placebo (Group II) and followed for 15 months. The control group comprised 9 untreated patients undergoing ECV. Treatment effectiveness was evaluated using a Bayesian model. Results: Eighteen months after AF reversion, 22 (81.5%) patients in Group I, 13 (54.2%) patients in Group II, and 1 (11.1%) patient in the control group remained in sinus rhythm. No differences were found between Group I patients who required ECV and Group II patients. Sinus rhythm was preserved in all Group I patients when it was achieved during amiodarone administration. Limiting adverse effects occurred in 3 (11.1%) patients in Group I. Conclusions: In patients regaining sinus rhythm after the first episode of persistent AF, a 3-month amiodarone treatment after reversion is a reasonable option for rhythm control.

Endocardial Approach for Substrate Ablation in Brugada Syndrome: Epicardial, Endocardial or Transmural Substrate?

Background: Radiofrequency ablation (RFA) in Brugada syndrome (BrS) has been performed both endocardially and epicardially. The substrate in BrS is thus unclear.Objectives: To investigate the functional endocardial substrate and its correlation with clinical, electrophysiological and ECG findings in order to guide an endocardial ablation.Methods: Thirteen patients (38.7±12.3 years old) with spontaneous type 1 ECG BrS pattern, inducible VF with programmed ventricular stimulation (PVS) and syncope without prodromes were enrolled. Before to endocardial mapping the patients underwent flecainide testing with the purpose of measuring the greatest ST-segment elevation for to be correlated with the size and location of substrate in the electro-anatomic map. Patients underwent endocardial bipolar and electro-anatomic mapping with the purpose of identify areas of abnormal electrograms (EGMs) as target for RFA and determine the location and size of the substrate.Results: When the greatest ST-segment elevation was in the 3rd intercostal space (ICS), the substrate was located upper in the longitudinal plane of the right ventricular outflow tract (RVOT) and a greatest ST-segment elevation in 4th ICS correspond with a location of substrate in lower region of longitudinal plane of RVOT. A QRS complex widening on its initial and final part, with prolonged transmural and regional depolarization time of RVOT corresponded to the substrate locateded in the anterior-lateral region of RVOT. A QRS complex widening rightwards and only prolonged transmural depolarization time corresponded with a substrate located in the anterior, anterior-septal or septal region of RVOT. RFA of endocardial substrate suppressed the inducibility and ECG BrS pattern during 34.7±15.5 months. After RFA, flecainide testing confirmed elimination of the ECG BrS pattern. Endocardial biopsy showed a correlation between functional and ultrastructural alterations in two patients.Keywords: Brugada syndrome; Radiofrequency catheter ablation; Electrocardiography; Mapping; Biopsy.Conclusion: Endocardial RFA can eliminate the BrS phenotype and inducibility during PVS.Fil: Tauber, Pablo E.. Centro Modelo del Corazón; Argentina. Gobierno de Tucumán. Ministerio de Salud. Hospital Centro de Salud "Zenón J. Santillán"; ArgentinaFil: Mansilla, Virginia. Centro Modelo del Corazón; ArgentinaFil: Brugada, Pedro. Free University of Brussels. Cardiovascular Division. Cardiovascular Institute; BélgicaFil: Sanchez, Sara Serafina del V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Honore, Stella Maris. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Elizari, Marcelo. Academia Nacional de Medicina de Buenos Aires; ArgentinaFil: Chain Molina, Sergio. Centro Modelo del Corazón; ArgentinaFil: Albano, Félix A.. Gobierno de Tucumán. Ministerio de Salud. Hospital Centro de Salud "Zenón J. Santillán"; ArgentinaFil: Corbalán, Ricardo R.. Centro Modelo del Corazón; ArgentinaFil: Figueroa Castellanos, Federico. Clínica Mayo; ArgentinaFil: Alzugaray, Damián. Abbott; Argentin

Right bundle branch block with left anterior hemiblock surgically induced in tetralogy of fallot: Relation to the mechanism of electrocardiographic changes in endocardial cushion defects

Four cases of tetralogy of Fallot in which right bundle branch block with left anterior hemiblock occurred after surgical repair are reported. In 2 cases right bundle branch block and left anterior hemiblock were present in the first postoperative tracings. In another case complete heart block was followed by “pure” right bundle branch block, and left anterior hemiblock occurred a few days later. In another case left anterior hemiblock was only transient, but right bundle branch block remained. The electrocardiographic changes were similar to those described in right bundle branch block with left anterior hemiblock occurring spontaneously in acquired heart disease. The cases presented also support the assumption that the electrocardiographic changes commonly observed in patients with endocardial cushion defects are due to the occurrence of right bundle branch block with left anterior hemiblock

Utilidad del Doppler pulsado tisular en la detección precoz de anormalidades diastólicas en familiares de primer grado de pacientes con miocardiopatía hipertrófica familiar

Introducción y objetivos. El Doppler pulsado tisular (DPT) permite analizar la función miocárdica regional independientemente de la precarga. Se realizó DPT a los familiares de primer grado de pacientes con miocardiopatía hipertrófica familiar (MHF) para detectar anormalidades precoces. Pacientes y método. Se estudió a 47 familiares de primer grado de pacientes con MHF (grupo GI) y se los comparó con un grupo control de 47 sujetos normales (grupo GII). Se realizó ecocardiografía 2D y Doppler pulsado de los flujos mitral y tricuspídeo. Mediante DPT en la pared lateral del ventrículo izquierdo, el ventrículo derecho y el septo interventricular se midieron las velocidades pico S', E' y A' y los períodos de relajación y contracción isovolumétricos. Se consideró función diastólica regional normal a una relación E'/A' > 1 y disfunción diastólica a una relación E'A'< 1. Resultados. No hubo alteraciones de la relajación ventricular en el GII (E'A' derecho, 1,78 ± 0,58; septo, 2,03 ± 0,53; izquierdo, 2,55 ± 0,80), mientras que en el GI la relación E'/A' permitió diferenciar 2 subgrupos: GIa de 37 familiares de primer grado que presentaron patrón de relajación normal (E'/A' derecho, 1,8 ± 0,44; septo, 2,07 ± 0,41; izquierdo, 2,35 ± 0,6, sin diferencias significativas con el grupo control) y GIb de 10 familiares de primer grado con relajación prolongada en el ventrículo derecho (E'/A', 0,70 ± 0,28; p < 0,001), con menor tendencia significativa en el septo (1,57 ± 0,49; p < 0,01) y el lateral izquierdo (1,85 ± 0,53; p < 0,01). Conclusiones. En familiares de primer grado de pacientes con MHF, el DPT permitió diferenciar anormalidades de la relajación ventricular en 10 de los 47 casos (21,3%), más manifiestas en el ventrículo derecho, que podrían ser un marcador preclínico de la enfermedad