Juan Martínez-Sánchez

Brugada-like electrocardiographic pattern induced by fever.

SAURA, D., et al.: Brugada‐Like Electrocardiographic Pattern Induced by Fever. The Brugada syndrome is characterized by a peculiar ST‐segment elevation in the right precordial leads and the propensity to develop ventricular arrhythmias. Mutations in a cardiac sodium channel gene have been linked to this syndrome and some experimental data suggest that the dysfunction of the mutated channel can be temperature sensitive. This report describes a patient in whom a typical Brugada ECG pattern developed in relation to fever but could not be reproduced at normal temperature on administration of flecainide. This case suggests that in some patients a Brugada‐like ECG may only manifest during a febrile state.

Radiofrequency catheter ablation of atriofascicular accessory pathways guided by discrete electrical potentials recorded at the tricuspid annulus.

Background: The purpose of this study was to test the feasibility of using the recording of discrete electrical potentials to guide radiofrequency catheter ablation of atriofascicular accessory pathways with Mahaim‐like properties. Methods and Results: Four patients (3 females, 1 male) who fulfilled criteria for having atriofascicular accessory pathways with Mahaim‐like properties and preexcited reciprocating tachycardia underwent radiofrequency catheter ablation. The mean age was 35 years (range 27–47). Symptoms were present for a mean of 10.5 years (range 6–18). Recording of discrete electrical potentials of the atriofascicular pathway was attempted by mapping the tricuspid annulus in sinus rhythm, during atrial pacing, and during reciprocating tachycardia. During atrial pacing, a mean of seven radiofrequency pulses (range 1–14), delivered to the tricuspid annulua at the area where electrical potentials were recorded, eliminated conduction through the atriofascicular accessory pathway in all patients. No complications occurred. Tachycardia did not reoccur during a mean follow‐up of 5 months (range 3–9). Conclusions: Recording of discrete electrical potentials at the tricuspid annulus identifies an optimal ablation site where radiofrequency current can safely eliminate conduction through atriofascicular accessory pathways with Mahaim‐like properties.

Utilidad de la estimulación auricular progresiva para evaluar la efectividad de la ablación de la vía lenta perinodal

Introduccion y objetivos Estudiar la utilidad de la estimulacion auricular progresiva para evaluar el efecto de la ablacion con cateter sobre la conduccion por via lenta en pacientes con taquicardia por reentrada nodal comun. Metodos Estudio prospectivo en pacientes remitidos para estudio electrofisiologico en los que se indujo taquicardia por reentrada nodal comun, empleando como grupo control a los pacientes en los que no se indujo. La estimulacion auricular progresiva se practico mediante la disminucion paulatina del ciclo de estimulacion hasta obtener un intervalo PR > RR o bloqueo auriculoventricular. Durante la estimulacion auricular programada se evaluo la presencia de doble fisiologia nodal siguiendo el criterio estandarizado. En el grupo en que se indujo taquicardia se repitio el estudio electrofisiologico 30 min despues de la ablacion. Resultados En el grupo con taquicardia por reentrada nodal comun (n = 85), 52 pacientes (61%) mostraron criterios de doble via nodal durante la estimulacion auricular programada y 66 (78%) mantenian PR > RR durante la estimulacion auricular progresiva. En el grupo control, la incidencia de estos criterios fue de 10/56 (18%) y 7/56 (12%), respectivamente. Tras la ablacion eficaz de via lenta (81/85), 37 mostraban doble via nodal durante la estimulacion auricular programada y uno tenia PR > RR durante estimulacion auricular progresiva (valor predictivo positivo de la ausencia de PR > RR para ablacion eficaz de via lenta del 98%). Conclusiones La estimulacion auricular progresiva muestra un intervalo PR > RR en la mayoria de los pacientes en los que se induce taquicardia por reentrada nodal comun y puede emplearse como un metodo sencillo y rapido para evaluar el efecto de las aplicaciones de radiofrecuencia sobre la conduccion por via lenta.

Influence of gender on the clinical characteristics and prognosis of patients hospitalized for heart failure

BACKGROUND AND OBJECTIVES The natural history of heart failure (HF) may be different in women due to their clinical characteristics, treatment and prognosis being distinct. Our aim was to describe the differential characteristics of women hospitalized with HF. METHODS We prospectively studied consecutive patients who were discharged with a diagnosis of HF (n=412). Clinical, laboratory, echocardiographic, and therapeutic variables were recorded at discharge. During follow-up (16 [9] months), all-cause mortality and the need for rehospitalization were recorded. RESULTS Compared with men, women (n=157, 38%) were older (75 [12] years vs. 71 [18] years, P< .001), had a higher prevalence of arterial hypertension (71% vs. 51%, P< .001), had more frequently been previously hospitalized for HF (36% vs. 25%, P=.02), had a higher prevalence of HF with a preserved left ventricular ejection fraction (LVEF) (44% vs. 21%, P<001), had less coronary disease (34% vs. 49%, P=.007), had more hypertensive cardiomyopathy (17% vs. 8%, P=.006), had worse renal function (52 [25] vs. 58 [25] mL/min per 1.73m2, P=.002), and had lower hemoglobin levels (12.1 [1.7] vs. 12.9 [1.9] g/dL, P< .001). This clinical profile resulted in less use of coronary angiography (22% vs. 37%, P=.001), antiplatelet drugs (45% vs. 62%, P=.001), and beta-blockers (39% vs. 50%, P=.03). In addition, women received statin treatment less often (31% vs. 45%, P=.003). Nevertheless, mortality (23% vs. 18%, P=.26) and the rehospitalization rate (44% vs. 46%, P=.81) were similar. In women, age (hazard ratio [HR] = 1.05, 95% confidence interval [CI] 1.01-1.09; P=.036) and anemia (HR = 2.43, 95% CI 1.16-5.12; P=.015) were independent predictors of death. CONCLUSIONS Women hospitalized for HF had a distinct clinical profile: their LVEF was greater and they more frequently had comorbid conditions. This led to different treatment, though prognosis was similar to that in men.

Extrasistolia ventricular desencadenante de la fibrilación ventricular

Introduccion y objetivos. Los mecanismos de inicio de la fibrilacion ventricular (FV) son poco conocidos. El objetivo de este estudio es analizar el inicio de la FV en los electrogramas almacenados en los desfibriladores automaticos implantables (DAI). Metodos. Hemos analizado los electrogramas de pacientes con DAI y al menos un episodio de FV. Resultados. De una poblacion de 250 pacientes portadores de DAI, 13 tuvieron al menos un episodio de FV, 10 varones y 3 mujeres (edad, 49 ± 22 anos), diagnosticados de sindrome de Brugada (n = 4), cardiopatia isquemica (n = 3), miocardiopatia dilatada (n = 2), miocardiopatia hipertrofica (n = 1), torsades de pointes por extrasistole ventricular (EV) con acoplamiento corto (n = 1), fibroelastosis cardiaca (n = 1) y FV idiopatica (n = 1). En 7 pacientes la FV fue el motivo del implante. Se registraron 31 episodios de FV (3 tormentas arritmicas). En cada paciente, todos los episodios comenzaron con una EV de la misma morfologia y similar intervalo de acoplamiento en los 7 pacientes con mas de un episodio (minutos-3 anos). Se objetivo ciclo corto-largo-corto en 2 pacientes. En 21 episodios, se registraron EV en ritmo sinusal que no desencadenaron FV. La morfologia, el intervalo de acoplamiento (409 ± 121 frente a 411 ± 123 ms) y el ciclo del latido sinusal precedente (801 ± 233 frente a 793 ± 230 ms) no presentaron diferencias significativas al compararlas con las EV inductoras de FV. Conclusiones. La FV espontanea se desencadena por EV en las tormentas arritmicas y en episodios aislados. En ocasiones las EV preceden a la FV sin desencadenarla

Characteristics of Sudden Death in Inherited Heart Disease

INTRODUCTION AND OBJECTIVES Cardiomyopathy and channelopathy are major causes of sudden death (SD). The little information available on the context in which SD occurs has come from only a few referral centers. The objective was to investigate the circumstances surrounding SD in families with inherited heart disease. METHODS The study included 152 SD patients (mean age 43+/-19 years) from 103 families. The reasons for inclusion were resuscitated SD in 7%, recent SD in 8%, and a diagnosis of cardiomyopathy or channelopathy in a living relative in 72%. Also, 13% were athletes. Family trees were constructed and each deaths circumstances were recorded. Autopsy and medical records were reviewed. RESULTS Overall, 18% of SDs occurred during physical exercise, 32% during normal daily activities, and 37% during rest or sleep. There was a significant association between male sex and SD: 111 males (73%) vs. 41 females (27%; P=.03). Exercise-related SD was associated with young age (P=.01). The percentage of SDs associated with exercise, stress or normal daily activities was significantly greater with cardiomyopathy than channelopathy (61% vs. 41%; P=.057). All athletes were male and the majority died during exercise (50% vs. 11% of non-athletes; P=.0002). Patients with Brugada syndrome had the highest percentage of SDs during rest or sleep (i.e. 47%). No clear trigger could be identified in 33%. CONCLUSIONS SD was common in inherited heart disease, which accounted for a significant number of cases. Males clearly predominated over females (ratio 3:1) among SD cases (irrespective of pathological type). Most SDs occurred during exercise or normal daily activities in cardiomyopathies and during rest or sleep in channelopathies. The percentage of exercise-related SDs (i.e. 18%) was higher than expected.

Premature Ventricular Complexes as a Trigger for Ventricular Fibrillation

INTRODUCTION AND OBJECTIVES The mechanisms that trigger ventricular fibrillation (VF) are poorly understood. The aim of this study was to analyze the initiation of VF in electrograms stored in implantable cardioverter-defibrillators (ICDs). METHODS We analyzed ICD electrograms from patients who had suffered at least one episode of VF. RESULTS Of 250 patients with ICDs, 13 (10 male and 3 female, age 49+/-22 years) had at least one episode of VF. The diagnoses were Brugada syndrome (n=4), ischemic heart disease (n=3), dilated cardiomyopathy (n=2), hypertrophic cardiomyopathy (n=1), short-coupled variant of torsades de pointes (n=1), endocardial fibroelastosis (n=1) and idiopathic VF (n=1). In 7 patients, VF was the reason for ICD implantation. Overall, 31 episodes of VF were recorded, including three episodes of arrhythmic storm. In the 7 patients who had more than one episode of VF (within minutes or up to 3 years apart), all episodes started with premature ventricular complexes (PVCs) that had the same morphology and similar coupling intervals. A short-long-short cycle was observed in 2 patients. In 21 episodes, PVCs that did not trigger VF were observed during sinus rhythm. There was no significant difference between them and PVCs that did trigger VF in terms of morphology, coupling interval (409+/-121 ms vs. 411+/-123 ms) or the preceding sinus rhythm RR interval (801+/-233 ms vs. 793+/-230 ms). CONCLUSIONS Spontaneous VF in the form of an arrhythmic storm or an isolated episode were triggered by PVCs. On occasions, PVCs preceded VF without triggering it.

ICD proarrhythmia as a consequence of an interaction with an algorithm to prevent atrial arrhythmias.

An episode of device‐related proarrhythmia is reported. Ventricular tachycardia was induced by ventricular pacing in a dual‐chamber implantable cardioverter‐defibrillator due to an inappropriate interaction of programmed device settings with the atrial preference pacing, an automatic algorithm designed to prevent atrial tachyarrhythmias.

Catheter Ablation of Focal Atrial Tachycardia From the Non-Coronary Aortic Sinus

We present the case of a 78-year-old woman with a history of allergy to acetylsalicylic acid, type-2 diabetes mellitus, and dyslipidaemia. In January 2008, she experienced dyspnoea and palpitations with no chest pain; she was seen to have incessant atrial tachycardia (AT) and severe left ventricular dysfunction (LVEF, 25%), which was presumed to be secondary. An electrophysiological study was carried out in February 2008 in which an AT with 2 different P-wave morphologies and a cycle length of 460 ms (Figure 1) was induced in a spontaneous, repeatable way using steady atrial stimulation. An activation map was made of the left atrium using the CARTO navigation system and a 4 mm Navistar F-Type catheter, which showed a focal By analysing the volumetric figures for the segment and the images of the longitudinal slice, as well as the transversal slice at the most obstructed point of the lumen using conventional IVUS and VH-IVUS, we conclude that the thrombotic material extracted from the patient’s DA was for the most part coded wrong by the ultrasound and coloured green, as if it were fibrous tissue. However, it is possible to deduce the approximate volume of the extracted thrombus by subtracting both total volumes, which gives us 4.7 μL. As a result, we find that VH-IVUS is a useful tool for studying the composition of coronary plaque, but it should be perfected technically for use in further studies that may help us to predict the plaque’s instability, vulnerability, and complications.

Duration of head-up tilt test for patients with suspected vasovagal syncope: a not-so-‘original article’

We have read with great interest the article published by Liu et al .1 about the duration of the tilt test in patients with suspected vasovagal syncope. We would like to highlight that a very similar paper (Head-up Tilt Test Potentiated with Nitroglycerin. What is the Optimal Duration of the Test after Administration of the Drug?2) was published by our group in 2002 in Rev Esp Cardiol , with an English …