ABSTRACT
INTRODUCTION AND OBJECTIVES: Cardiac resynchronization therapy is associated with improved quality of life and reduced morbidity and mortality in patients with severe ventricular dysfunction and wide QRS. However, its role in the reduction of ventricular arrhythmias is more controversial. METHODS: We compared the incidence of ventricular arrhythmias in patients who were undergoing cardiac resynchronization therapy with an implantable cardioverter-defibrillator in terms of the degree of echocardiographic response to resynchronization. Patients were classified in 3 subgroups;super-responders, responders, and nonresponders. RESULTS: We included 196 patients who were followed up for a median 30.1 months [interquartile range, 18.0-55.1 months]. We recorded the presence of ventricular arrhythmias in 37 patients (18.8%); 3 patients (5.9%) in the super-responder group had ventricular arrhythmias vs 14 (22.2%) among the responders and 20 (24.4%) in the group of nonresponders (P = .025). In multivariate analysis, the only independent predictors of the appearance of ventricular arrhythmias were secondary-prevention device implantation (odds ratio = 4.04; 95% confidence interval, 1.52-10.75; P=.005), absence of echocardiographic super-response (odds ratio=3.81; 95% confidence interval, 1.04-13.93; P=043), QRS >160 ms (odds ratio=2.39; 95% confidence interval, 1.00-1.35; P=.049) and treatment with amiodarone (odds ratio=2.47; 95% confidence interval, 1.03-5.91; P=.041). CONCLUSIONS: The patients classified as super-responders to cardiac resynchronization therapy had a significant reduction in incidence of ventricular arrhythmias by comparison with the other patients. Despite this, arrhythmic episodes do not completely disappear in this subgroup.
Subject(s)
Arrhythmias, Cardiac/therapy , Cardiac Resynchronization Therapy , Arrhythmias, Cardiac/physiopathology , Defibrillators, Implantable , Echocardiography , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment OutcomeABSTRACT
Introducción y objetivos La terapia de resincronización cardiaca se asocia a mejora de la calidad de vida y reducción de la morbimortalidad de los pacientes con disfunción ventricular grave y QRS ancho. Sobre su papel en la reducción de arritmias ventriculares, hay más discusión. Métodos Se comparó la incidencia de arritmias ventriculares en pacientes portadores de desfibrilador automático implantable con función de resincronización cardiaca, según el grado de respuesta ecocardiográfica a la resincronización. Se clasificó a los pacientes en tres subgrupos: superrespondedores, respondedores y no respondedores. Resultados Se incluyó a 196 pacientes seguidos durante una mediana de 30,1 [intervalo intercuartílico, 18,0-55,1] meses. Se documentó presencia de arritmias ventriculares en 37 pacientes (18,8%); 3 pacientes (5,9%) del grupo de superrespondedores presentaron arritmias ventriculares, en comparación con 14 (22,2%) del grupo de respondedores y 20 (24,4%) del grupo de no respondedores (p = 0,025). En el análisis multivariable, el implante del dispositivo en prevención secundaria (odds ratio = 4,04; intervalo de confianza del 95%, 1,52-10,75; p = 0,005), la ausencia de superrespuesta ecocardiográfica (odds ratio = 3,81; intervalo de confianza del 95%, 1,04-13,93; p = 0,043), un QRS > 160ms (odds ratio = 2,39; intervalo de confianza del 95%, 1,00-1,35; p = 0,049) y el tratamiento con amiodarona (odds ratio = 2,47; intervalo de confianza del 95%, 1,03-5,91; p = 0,041) fueron los únicos predictores independientes de aparición de arritmias ventriculares. Conclusiones: Los pacientes superrespondedores a la terapia de resincronización cardiaca presentan una disminución significativa en la incidencia de arritmias ventriculares respecto a los demás pacientes. Pese a ello, los episodios arrítmicos no llegan a desaparecer por completo en este subgrupo
Introduction and objectives: Cardiac resynchronization therapy is associated with improved quality of life and reduced morbidity and mortality in patients with severe ventricular dysfunction and wide QRS. However, its role in the reduction of ventricular arrhythmias is more controversial. Methods: We compared the incidence of ventricular arrhythmias in patients who were undergoing cardiac resynchronization therapy with an implantable cardioverter-defibrillator in terms of the degree of echocardiographic response to resynchronization. Patients were classified in 3 subgroups; superresponders, responders, and non responders. Results: We included 196 patients who were followed up for a median 30.1 months [interquartile range,18.0-55.1 months]. We recorded the presence of ventricular arrhythmias in 37 patients (18.8%);3 patients (5.9%) in the super-responder group had ventricular arrhythmias vs 14 (22.2%) among the responders and 20 (24.4%) in the group of non responders (P = .025). In multivariate analysis, the only independent predictors of the appearance of ventricular arrhythmias were secondary-prevention device implantation (odds ratio = 4.04; 95% confidence interval, 1.52-10.75; P=.005), absence of echocardiographic super-response (odds ratio=3.81; 95% confidence interval, 1.04-13.93; P = 043), QRS >160ms (odds ratio=2.39; 95% confidence interval, 1.00-1.35; P=.049) and treatment with amiodarone (odds ratio=2.47; 95% confidence interval, 1.03-5.91; P = .041). Conclusions: The patients classified as super-responders to cardiac resynchronization therapy had a significant reduction in incidence of ventricular arrhythmias by comparison with the other patients. Despite this, arrhythmic episodes do not completely disappear in this subgroup
