Clinical Findings and Prognosis of Danon Disease. An Analysis of the Spanish Multicenter Danon Registry.

INTRODUCTION AND OBJECTIVES: Danon disease (DD) is caused by mutations in the LAMP2 gene. It is considered a multisystemic disease characterized by hypertrophic cardiomyopathy with pre-excitation and extreme hypertrophy, intellectual disability, myopathy, childhood presentation, and worse prognosis in men. There are scarce data on the clinical characteristics and prognosis of DD. METHODS: We analyzed the clinical records of patients with DD from 10 Spanish hospitals. RESULTS: Twenty-seven patients were included (mean age, 31 ± 19 years; 78% women). Male patients showed a high prevalence of extracardiac manifestations: myopathy (80%), learning disorders (83%), and visual alterations (60%), which were uncommon findings in women (5%, 0%, and 27%, respectively). Although hypertrophic cardiomyopathy was the most common form of heart disease (61%), the mean maximum wall thickness was 15 ± 7 mm and dilated cardiomyopathy was present in 12 patients (10 women). Pre-excitation was found in only 11 patients (49%). Age at presentation was older than 20 years in 16 patients (65%). After a median follow-up of 4 years (interquartile range, 2-9), 4 men (67%) and 9 women (43%) died or required a transplant. Cardiac disease and adverse events occurred later in women (37 ± 9 vs 23 ± 16 and 36 ± 20 vs 20 ± 11 years, respectively). CONCLUSIONS: The clinical characteristics of DD differ substantially from traditional descriptions: age at presentation of DD is older, the disease is not multisystemic in women, and pre-excitation is infrequent.

Flecainide Reduces Ventricular Arrhythmias in Patients With Genotype RyR2-positive Catecholaminergic Polymorphic Ventricular Tachycardia.

INTRODUCTION AND OBJECTIVES: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited disease characterized by polymorphic or bidirectional ventricular arrhythmias (VA) triggered by physical or emotional stress in young people with a structurally normal heart. Beta-blockers are the cornerstone of treatment, while flecainide has recently been incorporated into the therapeutic arsenal. The aim of this study was to report our experience with this drug. METHODS: The cohort included 174 genotype-positive CPVT-patients from 7 families. We collected data from patients who were receiving flecainide and analyzed the indications, adverse effects and dosage, clinical events, VA and arrhythmic window during exercise testing, and implantable cardioverter-defibrillator (ICD) shocks during follow-up. RESULTS: Eighteen patients (10.4%) received flecainide; 17 patients in combination with beta-blockers, and 1 patient as monotherapy due to beta-blocker intolerance. None of the patients presented side effects. In 13 patients (72.2%) the indication was the persistence of exercise-induced VA and in 5 patients (27.7%) persistent ICD-shocks, despite on beta-blockers. After flecainide initiation, the exercise-induced VA quantitative score was reduced by more than 50% in 66.7% of the members of family 1 (32.76 ± 84.06 vs 74.38 ± 153.86; P = .018). The arrhythmic window was reduced (5.8 ± 11.9 bpm vs 19.69 ± 21.27 bpm; P = .007), and 4 of 5 patients with appropriate ICD shocks experienced no further shocks in the follow-up. CONCLUSIONS: In CPVT-patients flecainide reduces clinical events, exercise-induced VA, the arrhythmic window, and ICD shocks, with good tolerance.

Características clínicas y pronóstico de la enfermedad de Danon. Análisis del registro multicéntrico español / Clinical findings and prognosis of danon disease. An analysis of the Spanish multicenter danon registry

Introducción y objetivos: La enfermedad de Danon (ED) es una enfermedad producida por mutaciones en el gen LAMP2. Se la considera una enfermedad multisistémica caracterizada por miocardiopatía hipertrófica con preexcitación e hipertrofia extrema, discapacidad intelectual, miopatía, presentación infantil y peor pronóstico en varones. Hay pocas series que permitan conocer las características clínicas y el pronóstico de la ED. Métodos: Se analizaron los registros clínicos de los pacientes con ED de 10 hospitales españoles. Resultados: Se incluyó a 27 pacientes (edad, 31 +/- 19 años; el 78% mujeres). Los varones mostraron una elevada prevalencia de manifestaciones extracardiacas -miopatía (80%), trastornos del aprendizaje (83%) y alteraciones visuales (60%)- que eran infrecuentes en las mujeres (el 5, el 0 y el 27% respectivamente). Aunque la miocardiopatía hipertrófica era la cardiopatía más habitual (61%), el grosor ventricular máximo fue 15 +/- 7 mm y 12 pacientes (10 mujeres) presentaron miocardiopatía dilatada. Solo 11 pacientes (49%) mostraron preexcitación y en 16 (65%) la enfermedad se inició después de los 20 años. Tras una mediana de seguimiento de 4 años [intervalo intercuartílico, 2-9], 4 varones (67%) y 9 mujeres (43%) fallecieron o se sometieron a trasplante. El daño cardiaco y los eventos adversos ocurrieron más tardíamente en las mujeres (37 +/- 9 frente a 23 +/- 16 años y 36 +/- 20 frente a 20 +/- 11 años). Conclusiones: Las características clínicas de la ED difieren sustancialmente de lo considerado tradicionalmente. La edad de presentación de la ED es más tardía, no se expresa como una enfermedad multisistémica en las mujeres y la preexcitación es poco frecuente

Introduction and objectives: Danon disease (DD) is caused by mutations in the LAMP2 gene. It is considered a multisystemic disease characterized by hypertrophic cardiomyopathy with pre-excitation and extreme hypertrophy, intellectual disability, myopathy, childhood presentation, and worse prognosis in men. There are scarce data on the clinical characteristics and prognosis of DD. Methods: We analyzed the clinical records of patients with DD from 10 Spanish hospitals. Results: Twenty-seven patients were included (mean age, 31 +/- 19 years; 78% women). Male patients showed a high prevalence of extracardiac manifestations: myopathy (80%), learning disorders (83%), and visual alterations (60%), which were uncommon findings in women (5%, 0%, and 27%, respectively). Although hypertrophic cardiomyopathy was the most common form of heart disease (61%), the mean maximum wall thickness was 15 +/- 7 mm and dilated cardiomyopathy was present in 12 patients (10 women). Pre-excitation was found in only 11 patients (49%). Age at presentation was older than 20 years in 16 patients (65%). After a median follow-up of 4 years (interquartile range, 2-9), 4 men (67%) and 9 women (43%) died or required a transplant. Cardiac disease and adverse events occurred later in women (37 +/- 9 vs 23 +/- 16 and 36 +/- 20 vs 20 +/- 11 years, respectively). Conclusions: The clinical characteristics of DD differ substantially from traditional descriptions: age at presentation of DD is older, the disease is not multisystemic in women, and pre-excitation is infrequent

La flecainida reduce las arritmias ventriculares en pacientes con taquicardia ventricular polimórfica catecolaminérgica genotipo RyR2 positivo / Flecainide reduces ventricular arrhythmias in patients with genotype RyR2-positive catecholaminergic polymorphic ventricular tachycardia

Introducción y objetivos: La taquicardia ventricular polimórfica catecolaminérgica (TVPC) es una enfermedad hereditaria caracterizada por arritmias ventriculares (AV) polimórficas o bidireccionales desencadenadas por estrés físico o emocional en jóvenes con corazón estructuralmente normal. El pilar del tratamiento son los bloqueadores beta y recientemente se ha incorporado la flecainida al arsenal terapéutico. El objetivo de este trabajo es exponer nuestra experiencia con su uso. Métodos: De un total de 174 pacientes pertenecientes a 7 familias afectadas de TVPC con genotipo positivo, se analizó a los que tomaron flecainida. Se valoraron la indicación, los efectos secundarios, la dosificación, los eventos clínicos, las AV y la ventana arrítmica en las pruebas de esfuerzo y las descargas del desfibrilador automático (DAI). Resultados: Recibieron flecainida 18 pacientes (10,4%); 17 en combinación con bloqueadores beta y 1 como tratamiento único por intolerancia al bloqueador beta. Ningún paciente sufrió efectos secundarios. La indicación fue la persistencia de AV complejas en la prueba de esfuerzo en 13 pacientes (72,2%) y descargas frecuentes del DAI en los otros 5 (27,8%). En el 66,7% de la familia 1, la puntuación cuantitativa de AV en la prueba de esfuerzo se redujo más de un 50% (32,76 ± 84,06 frente a 74,38 ± 153,86 lpm; p = 0,018). La ventana arrítmica fue menor (5,8 ± 11,9 frente a 19,69 ± 21,27 lpm; p = 0,007) y 4 de los 5 pacientes con descargas apropiadas del DAI no sufrieron más descargas. Conclusiones: En pacientes con TVPC, la flecainida reduce los eventos clínicos, las AV, la ventana arrítmica y las descargas del DAI y los pacientes la toleran bien (AU)

Introduction and objectives: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited disease characterized by polymorphic or bidirectional ventricular arrhythmias (VA) triggered by physical or emotional stress in young people with a structurally normal heart. Beta-blockers are the cornerstone of treatment, while flecainide has recently been incorporated into the therapeutic arsenal. The aim of this study was to report our experience with this drug. Methods: The cohort included 174 genotype-positive CPVT-patients from 7 families. We collected data from patients who were receiving flecainide and analyzed the indications, adverse effects and dosage, clinical events, VA and arrhythmic window during exercise testing, and implantable cardioverter-defibrillator (ICD) shocks during follow-up. Results: Eighteen patients (10.4%) received flecainide; 17 patients in combination with beta-blockers, and 1 patient as monotherapy due to beta-blocker intolerance. None of the patients presented side effects. In 13 patients (72.2%) the indication was the persistence of exercise-induced VA and in 5 patients (27.7%) persistent ICD-shocks, despite on beta-blockers. After flecainide initiation, the exercise-induced VA quantitative score was reduced by more than 50% in 66.7% of the members of family 1 (32.76 ± 84.06 vs 74.38 ± 153.86; P = .018). The arrhythmic window was reduced (5.8 ± 11.9 bpm vs 19.69 ± 21.27 bpm; P = .007), and 4 of 5 patients with appropriate ICD shocks experienced no further shocks in the follow-up. Conclusions: In CPVT-patients flecainide reduces clinical events, exercise-induced VA, the arrhythmic window, and ICD shocks, with good tolerance (AU)