Factores predictores de aparición de fibrilación auricular en pacientes con miocardiopatía dilatada / Predicting factors of atrial fibrillation in patients with dilated cardiomyopathy

Resumen Introducción El uso de terapia anticoagulante en pacientes con miocardiopatía dilatada es controvertido. El riesgo hemorrágico hace que habitualmente no se use en pacientes en ritmo sinusal. Objetivo Analizar los factores predictores de fibrilación auricular (FA) en pacientes con miocardiopatía dilatada y fracción de eyección del ventrículo izquierdo (FEVI) < 40. Método: Se estudiaron los pacientes incluidos en el registro multicéntrico UMBRELLA a quienes se había implantado un desfibrilador (DAI) bicameral o tricameral y que presentaban miocardiopatía dilatada isquémica o no isquémica y FEVI < 40%. Se definió FA como cualquier episodio > 30 segundos de duración y una frecuencia auricular > 175 latidos por minuto. Resultados Se incluyeron 684 enfermos. La mediana de edad fue de 70 años (rango intercuartílico [RIQ]: 62-77). El 79.1% eran varones. La FEVI fue < 30% en el 76.3%. El 87.3% presentaban insuficiencia cardiaca (ICC) clínica. Se implantó un DAI resincronizador en el 59.5%. El 51.2% tenían bloqueo de rama izquierda del haz de His y el 7.1% de rama derecha (BRDHH). Se documentó FA en el 49% de los enfermos con una mediana de seguimiento de 29.93 meses (RIQ: 14.78-45.63). Las variables que se relacionaron con la aparición de FA fueron la presencia de ICC (hazard ratio [HR]: 2; intervalo de confianza del 95% [IC 95%]: 1.31-3.04; p = 0.001), el BRDHH (HR: 1.48; IC 95%: 1-2-18; p = 0.045), el ictus previo (HR: 2.11; IC 95%: 1.4-3.19; p < 0.001) y la edad > 75 años (HR: 1.21; IC 95%: 1.05-1.40; p = 0.008). Conclusiones La edad > 75 años, el BRDHH, la ICC y el ictus previo predicen la aparición de FA en la población con miocardiopatía dilatada y FEVI < 40%.

Abstract Introduction Anticoagulant treatment in patients with dilated cardiomyopathy and sinus rhythm is controversial due to haemorrhage risk. Objective To analyze the factors predicting atrial fibrillation (AF) in patients with dilated cardiomyopathy and ejection fraction (LVEF) < 40%. Method All patients included in UMBRELLA multicentre registry without AF, who had a dual or three-chamber implantable cardiac defibrillator (ICD), dilated cardiomyopathy and LVEF < 40% were included. AF was defined as any episode > 30 seconds of duration and atrial frequency > 175 bpm. Results 684 patients were included. Median age was 70 years (IQR 62-77); 79.1% were male. LVEF was < 30% in 76.3% of cases; 87.3% presented clinical heart failure (CHF). A CRT-D was implanted in 59.5%; 51.2% of patients presented Left Bundle Branch Block (LBBB) and 7.1% presented Right Bundle Branch Block (RBBB). AF was documented in 49% of patients, with a median follow-up of 29.93 months (IQR: 14.78-45.63). The presence of CHF (HR: 2; 95% CI: 1.31-3.04; p = 0.001), RBBB (HR: 1.48; 95% CI: 1-2-18; p = 0.045), previous stroke (HR: 2.11; 95% CI: 1.4-3.19; p < 0.001) and age > 75 years (HR: 1.21; 95% CI: 1.05-1.40; p = 0.008) were associated with diagnosis of AF. Conclusions Age > 75 years, RBBB, CHF and previous stroke are predictors of AF development in the population with dilated cardiomyopathy and LVEF < 40%.

Impact of dynamic physical exercise on high-risk definite arrhythmogenic right ventricular cardiomyopathy.

INTRODUCTION: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is an inherited cardiomyopathy characterized by ventricular arrhythmias and heart failure. The variable phenotype suggesting that determined environmental factors may have an influence. The aim of our study was to discover the impact of the dynamic physical activity on patients with high-risk definite ARVC/D. METHODS AND RESULTS: Collection of data on physical activity at the time of diagnosis was conducted at an in-person clinical interview. The intensity of the activity was classified in accordance with the mean frequency of weekly physical exercise sessions in the 10 years before diagnosis and into the following three groups of dynamic activity: high/competitive (>3 h/wk), moderate (1 to 3 h) and minimal/inactive (<1 h). Seventeen patients practiced high dynamic physical activities. The intensity of dynamic activity was classified into three groups: 8 of high intensity, 9 moderate, and 19 inactive. The first major arrhythmic event and occurrence of severe right ventricular dysfunction were earlier in the high-intensity exercise group, followed by the moderate intensity group and at a later age in the low-intensity/inactive group. CONCLUSIONS: Dynamic exercise could be directly associated with the severity of the phenotype in relation to the precocity of major ventricular arrhythmic events and right ventricular systolic dysfunction in patients with high-risk definite ARVC/D.

Usefulness of Genetic Study by Next-generation Sequencing in High-risk Arrhythmogenic Cardiomyopathy.

INTRODUCTION AND OBJECTIVES: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by progressive fibrofatty replacement of predominantly right ventricular myocardium. This cardiomyopathy is a frequent cause of sudden cardiac death in young people and athletes. The aim of our study was to determine the incidence of pathological or likely pathological desmosomal mutations in patients with high-risk definite ARVC. METHODS: This was an observational, retrospective cohort study, which included 36 patients diagnosed with high-risk ARVC in our hospital between January 1998 and January 2015. Genetic analysis was performed using next-generation sequencing. RESULTS: Most patients were male (28 patients, 78%) with a mean age at diagnosis of 45 ± 18 years. A pathogenic or probably pathogenic desmosomal mutation was detected in 26 of the 35 index cases (74%): 5 nonsense, 14 frameshift, 1 splice, and 6 missense. Novel mutations were found in 15 patients (71%). The presence or absence of desmosomal mutations causing the disease and the type of mutation were not associated with specific electrocardiographic, clinical, arrhythmic, anatomic, or prognostic characteristics. CONCLUSIONS: The incidence of pathological or likely pathological desmosomal mutations in ARVC is very high, with most mutations causing truncation. The presence of desmosomal mutations was not associated with prognosis.

Serum levels of interleukin-2 predict the recurrence of atrial fibrillation after pulmonary vein ablation.

AIMS: Interleukin-2 has a significant antitumor activity in some types of cancer, and has been associated with the development of atrial fibrillation (AF). In addition, IL-2 serum levels in recent onset AF have been related with pharmaceutical cardioversion outcomes. We evaluated the hypothesis that a relationship exists between inflammation and the outcome of catheter ablation of AF. METHODS: We studied 44 patients with paroxysmal AF who underwent catheter ablation. Patients with structural heart disease, coronary artery or valve disease, active inflammatory disease, known or suspected neoplasm, endocrinopathies, or exposure to anti-inflammatory drugs were excluded. All study participants underwent evaluation with a standardized protocol, including echocardiography, and cytokine levels of interleukin-2, interleukin-4, interleukin-6, interleukin-10, tumour necrosis factor-alpha, and gamma-interferon determination before procedure. Clinical and electrocardiographic follow-up were performed with Holter-ECG at 3, 6 and 12months in order to know if sinus rhythm was maintained. RESULTS: After catheter ablation of the 44 patients included (53±10years, 27.3% female), all patients returned to sinus rhythm. During the first year of follow-up seven patients (15.9%) experienced recurrence of AF. The demographics, clinical and echocardiographic features, and pharmacological treatments of these patients were similar to those who maintained sinus rhythm. The only independent factor predictive of recurrence of AF was an elevated level of IL-2 (OR 1.18, 95% CI 1.12-1.38). CONCLUSIONS: High serum levels of interleukin-2, a pro-inflammatory non-vascular cytokine, are associated with the recurrence of AF in patients undergoing catheter ablation.

[Spanish implantable cardioverter-defibrillator registry. Seventh official report of the spanish society of cardiology working group on implantable cardioverter-defibrillators (2010)]. / Registro Español de Desfibrilador Automático Implantable. VII Informe Oficial del Grupo de Trabajo de Desfibrilador Automático Implantable de la Sociedad Española de Cardiología (2010).

INTRODUCTION AND OBJECTIVES: The authors summarize the findings of the Spanish Implantable Cardioverter-Defibrillator Registry for 2010 compiled by the Spanish Society of Cardiology Working Group on Implantable Cardioverter-Defibrillators. METHODS: Members of the Spanish Society of Cardiology were prospectively surveyed; data were recorded voluntarily by each implantation team on one-page questionnaires. RESULTS: In total, 4627 device implantations were reported, comprising 85.6% of the overall estimated number of implantations. The reported implantation rate was 100.61 per million population and the estimated total implantation rate was 117.50 per million. The proportion of first implantations was 73.87%. We collected data from 143 hospitals (9 more than in 2009). The majority of the implantable cardioverter-defibrillator implantations were performed in men (81%). The mean age was 62.5 ± 13 years. Most of the patients had severe or moderate-to-severe ventricular dysfunction and were in New York Heart Association functional class II. Ischemic heart disease was the most frequent underlying cardiac condition, followed by dilated cardiomyopathy. The number of implantable cardioverter-defibrillator implantations indicated for primary prevention increased over the previous year and now accounts for 65.6% of first implantations. In all, 76.1% of the implantable cardioverter-defibrillator implantations were performed by cardiac electrophysiologists. CONCLUSIONS: The 2010 Spanish Implantable Cardioverter-Defibrillator Registry includes data on almost 86% of all the implantable cardioverter-defibrillator implantations performed in Spain. Although the number has continued to increase, it still remains far lower than the European average. There has been a significant increase in the number of implantations indicated for primary prevention.

Preventing ventricular dysfunction in pacemaker patients without advanced heart failure: rationale and design of the PREVENT-HF study.

AIMS: Right ventricular (RV) pacing has been shown to cause heart failure symptoms in patients with and without previous systolic left ventricular (LV) dysfunction. The aim here was to evaluate the preventive effect of biventricular pacing vs. RV apical pacing in patients with indication for permanent ventricular pacing. Methods PREVENT-HF is an ongoing multicentre randomized controlled pilot study designed to assess whether biventricular pacing is superior to RV pacing in patients receiving a bradycardia pacemaker for standard indications. Patients with Class I or IIa indication according to ACC/AHA guidelines for cardiac pacing judged likely to require high (>or=80%) ventricular pacing are randomized to receive either RV or biventricular stimulation. Patients are ineligible if younger than 18 years, have Class III or IV heart failure, or experienced a recent myocardial infarction or cardiac surgery. Echocardiographic parameters of LV function are assessed at baseline, 6 months, and 12 months. The primary endpoint is change in LV end diastolic volume. Secondary outcomes include LV ejection fraction, mortality, morbidity, and mitral regurgitation. In subsets of patients, NT-pro-BNP and oxygen uptake are analysed. Centres in Spain (five), Italy (four), and Germany (seven) will enrol 100 patients. CONCLUSION: PREVENT-HF will contribute to better define the role of chronic biventricular pacing for advanced atrioventricular block.